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chromium / external / github.com / WebAssembly / binaryen / refs/heads/travis_cleanup / . / src / asm2wasm.h
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/*
* Copyright 2015 WebAssembly Community Group participants
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
//
// asm.js-to-WebAssembly translator. Uses the Emscripten optimizer
// infrastructure.
//
#ifndef wasm_asm2wasm_h
#define wasm_asm2wasm_h
#include "abi/js.h"
#include "asm_v_wasm.h"
#include "asmjs/shared-constants.h"
#include "emscripten-optimizer/optimizer.h"
#include "ir/bits.h"
#include "ir/branch-utils.h"
#include "ir/literal-utils.h"
#include "ir/module-utils.h"
#include "ir/trapping.h"
#include "ir/utils.h"
#include "mixed_arena.h"
#include "parsing.h"
#include "pass.h"
#include "passes/passes.h"
#include "shared-constants.h"
#include "support/debug.h"
#include "wasm-builder.h"
#include "wasm-emscripten.h"
#include "wasm-module-building.h"
#include "wasm.h"
#define DEBUG_TYPE "asm2wasm"
namespace wasm {
using namespace cashew;
// Names
Name I32_CTTZ("i32_cttz");
Name I32_CTPOP("i32_ctpop");
Name I32_BC2F("i32_bc2f");
Name I32_BC2I("i32_bc2i");
Name I64("i64");
Name I64_CONST("i64_const");
Name I64_ADD("i64_add");
Name I64_SUB("i64_sub");
Name I64_MUL("i64_mul");
Name I64_UDIV("i64_udiv");
Name I64_SDIV("i64_sdiv");
Name I64_UREM("i64_urem");
Name I64_SREM("i64_srem");
Name I64_AND("i64_and");
Name I64_OR("i64_or");
Name I64_XOR("i64_xor");
Name I64_SHL("i64_shl");
Name I64_ASHR("i64_ashr");
Name I64_LSHR("i64_lshr");
Name I64_EQ("i64_eq");
Name I64_NE("i64_ne");
Name I64_ULE("i64_ule");
Name I64_SLE("i64_sle");
Name I64_UGE("i64_uge");
Name I64_SGE("i64_sge");
Name I64_ULT("i64_ult");
Name I64_SLT("i64_slt");
Name I64_UGT("i64_ugt");
Name I64_SGT("i64_sgt");
Name I64_TRUNC("i64_trunc");
Name I64_SEXT("i64_sext");
Name I64_ZEXT("i64_zext");
Name I64_S2F("i64_s2f");
Name I64_S2D("i64_s2d");
Name I64_U2F("i64_u2f");
Name I64_U2D("i64_u2d");
Name I64_F2S("i64_f2s");
Name I64_D2S("i64_d2s");
Name I64_F2U("i64_f2u");
Name I64_D2U("i64_d2u");
Name I64_BC2D("i64_bc2d");
Name I64_BC2I("i64_bc2i");
Name I64_CTTZ("i64_cttz");
Name I64_CTLZ("i64_ctlz");
Name I64_CTPOP("i64_ctpop");
Name F32_COPYSIGN("f32_copysign");
Name F64_COPYSIGN("f64_copysign");
Name LOAD1("load1");
Name LOAD2("load2");
Name LOAD4("load4");
Name LOAD8("load8");
Name LOADF("loadf");
Name LOADD("loadd");
Name STORE1("store1");
Name STORE2("store2");
Name STORE4("store4");
Name STORE8("store8");
Name STOREF("storef");
Name STORED("stored");
Name FTCALL("ftCall_");
Name MFTCALL("mftCall_");
Name MAX_("max");
Name MIN_("min");
Name ATOMICS("Atomics");
Name ATOMICS_LOAD("load");
Name ATOMICS_STORE("store");
Name ATOMICS_EXCHANGE("exchange");
Name ATOMICS_COMPARE_EXCHANGE("compareExchange");
Name ATOMICS_ADD("add");
Name ATOMICS_SUB("sub");
Name ATOMICS_AND("and");
Name ATOMICS_OR("or");
Name ATOMICS_XOR("xor");
Name I64_ATOMICS_LOAD("i64_atomics_load");
Name I64_ATOMICS_STORE("i64_atomics_store");
Name I64_ATOMICS_AND("i64_atomics_and");
Name I64_ATOMICS_OR("i64_atomics_or");
Name I64_ATOMICS_XOR("i64_atomics_xor");
Name I64_ATOMICS_ADD("i64_atomics_add");
Name I64_ATOMICS_SUB("i64_atomics_sub");
Name I64_ATOMICS_EXCHANGE("i64_atomics_exchange");
Name I64_ATOMICS_COMPAREEXCHANGE("i64_atomics_compareExchange");
Name TEMP_DOUBLE_PTR("tempDoublePtr");
Name EMSCRIPTEN_DEBUGINFO("emscripten_debuginfo");
// Utilities
static WASM_NORETURN void abort_on(std::string why, Ref element) {
std::cerr << why << ' ';
element->stringify(std::cerr);
std::cerr << '\n';
abort();
}
static WASM_NORETURN void abort_on(std::string why, IString element) {
std::cerr << why << ' ' << element.str << '\n';
abort();
}
Index indexOr(Index x, Index y) { return x ? x : y; }
// useful when we need to see our parent, in an asm.js expression stack
struct AstStackHelper {
static std::vector<Ref> astStack;
AstStackHelper(Ref curr) { astStack.push_back(curr); }
~AstStackHelper() { astStack.pop_back(); }
Ref getParent() {
if (astStack.size() >= 2) {
return astStack[astStack.size() - 2];
} else {
return Ref();
}
}
};
std::vector<Ref> AstStackHelper::astStack;
static bool startsWith(const char* string, const char* prefix) {
while (1) {
if (*prefix == 0) {
return true;
}
if (*string == 0) {
return false;
}
if (*string++ != *prefix++) {
return false;
}
}
};
//
// Asm2WasmPreProcessor - does some initial parsing/processing
// of asm.js code.
//
struct Asm2WasmPreProcessor {
bool memoryGrowth = false;
bool debugInfo = false;
std::vector<std::string> debugInfoFileNames;
std::unordered_map<std::string, Index> debugInfoFileIndices;
char* allocatedCopy = nullptr;
~Asm2WasmPreProcessor() {
if (allocatedCopy) {
free(allocatedCopy);
}
}
char* process(char* input) {
// emcc --separate-asm modules can look like
//
// Module["asm"] = (function(global, env, buffer) {
// ..
// });
//
// we need to clean that up.
if (*input == 'M') {
size_t num = strlen(input);
while (*input != 'f') {
input++;
num--;
}
char* end = input + num - 1;
while (*end != '}') {
*end = 0;
end--;
}
}
// asm.js memory growth uses a quite elaborate pattern. Instead of parsing
// and matching it, we do a simpler detection on emscripten's asm.js output
// format
const char* START_FUNCS = "// EMSCRIPTEN_START_FUNCS";
char* marker = strstr(input, START_FUNCS);
if (marker) {
// look for memory growth code just up to here, as an optimization
*marker = 0;
}
// this can only show up in growth code, as normal asm.js lacks "true"
char* growthSign = strstr(input, "return true;");
if (growthSign) {
memoryGrowth = true;
// clean out this function, we don't need it. first where it starts
char* growthFuncStart = growthSign;
while (*growthFuncStart != '{') {
growthFuncStart--; // skip body
}
while (*growthFuncStart != '(') {
growthFuncStart--; // skip params
}
while (*growthFuncStart != ' ') {
growthFuncStart--; // skip function name
}
while (*growthFuncStart != 'f') {
growthFuncStart--; // skip 'function'
}
assert(strstr(growthFuncStart, "function ") == growthFuncStart);
char* growthFuncEnd = strchr(growthSign, '}');
assert(growthFuncEnd > growthFuncStart + 5);
growthFuncStart[0] = '/';
growthFuncStart[1] = '*';
growthFuncEnd--;
growthFuncEnd[0] = '*';
growthFuncEnd[1] = '/';
}
if (marker) {
*marker = START_FUNCS[0];
}
// handle debug info, if this build wants that.
if (debugInfo) {
// asm.js debug info comments look like
// ..command..; //@line 4 "tests/hello_world.c"
// we convert those into emscripten_debuginfo(file, line)
// calls, where the params are indices into a mapping. then
// the compiler and optimizer can operate on them. after
// that, we can apply the debug info to the wasm node right
// before it - this is guaranteed to be correct without opts,
// and is usually decently accurate with them.
// an upper bound on how much more space we need as a multiple of the
// original
const auto SCALE_FACTOR = 1.25;
// an upper bound on how much we write for each debug info element itself
const auto ADD_FACTOR = 100;
auto size = strlen(input);
auto upperBound = Index(size * SCALE_FACTOR) + ADD_FACTOR;
char* copy = allocatedCopy = (char*)malloc(upperBound);
char* end = copy + upperBound;
char* out = copy;
std::string DEBUGINFO_INTRINSIC = EMSCRIPTEN_DEBUGINFO.str;
auto DEBUGINFO_INTRINSIC_SIZE = DEBUGINFO_INTRINSIC.size();
const char* UNKNOWN_FILE = "(unknown)";
bool seenUseAsm = false;
while (input[0]) {
if (out + ADD_FACTOR >= end) {
Fatal() << "error in handling debug info";
}
if (startsWith(input, "//@line")) {
char* linePos = input + 8;
char* lineEnd = strpbrk(input + 8, " \n");
if (!lineEnd) {
// comment goes to end of input
break;
}
input = lineEnd + 1;
std::string file;
if (*lineEnd == ' ') {
// we have a file
char* filePos = strpbrk(input, "\"\n");
if (!filePos) {
// goes to end of input
break;
}
if (*filePos == '"') {
char* fileEnd = strpbrk(filePos + 1, "\"\n");
input = fileEnd + 1;
*fileEnd = 0;
file = filePos + 1;
} else {
file = UNKNOWN_FILE;
input = filePos + 1;
}
} else {
// no file, we found \n
file = UNKNOWN_FILE;
}
*lineEnd = 0;
std::string line = linePos;
auto iter = debugInfoFileIndices.find(file);
if (iter == debugInfoFileIndices.end()) {
Index index = debugInfoFileNames.size();
debugInfoFileNames.push_back(file);
debugInfoFileIndices[file] = index;
}
std::string fileIndex = std::to_string(debugInfoFileIndices[file]);
// write out the intrinsic
strcpy(out, DEBUGINFO_INTRINSIC.c_str());
out += DEBUGINFO_INTRINSIC_SIZE;
*out++ = '(';
strcpy(out, fileIndex.c_str());
out += fileIndex.size();
*out++ = ',';
strcpy(out, line.c_str());
out += line.size();
*out++ = ')';
*out++ = ';';
} else if (!seenUseAsm &&
(startsWith(input, "asm'") || startsWith(input, "asm\""))) {
// end of "use asm" or "almost asm"
// skip the end of "use asm"; (5 chars, a,s,m," or ',;)
const auto SKIP = 5;
seenUseAsm = true;
memcpy(out, input, SKIP);
out += SKIP;
input += SKIP;
// add a fake import for the intrinsic, so the module validates
std::string import =
"\n var emscripten_debuginfo = env.emscripten_debuginfo;";
strcpy(out, import.c_str());
out += import.size();
} else {
*out++ = *input++;
}
}
if (out >= end) {
Fatal() << "error in handling debug info";
}
*out = 0;
input = copy;
}
return input;
}
};
static Call* checkDebugInfo(Expression* curr) {
if (auto* call = curr->dynCast<Call>()) {
if (call->target == EMSCRIPTEN_DEBUGINFO) {
return call;
}
}
return nullptr;
}
// Debug info appears in the ast as calls to the debug intrinsic. These are
// usually after the relevant node. We adjust them to a position that is not
// dce-able, so that they are not trivially removed when optimizing.
struct AdjustDebugInfo
: public WalkerPass<PostWalker<AdjustDebugInfo, Visitor<AdjustDebugInfo>>> {
bool isFunctionParallel() override { return true; }
Pass* create() override { return new AdjustDebugInfo(); }
AdjustDebugInfo() { name = "adjust-debug-info"; }
void visitBlock(Block* curr) {
// look for a debug info call that is unreachable
if (curr->list.size() == 0) {
return;
}
auto* back = curr->list.back();
for (Index i = 1; i < curr->list.size(); i++) {
if (checkDebugInfo(curr->list[i]) && !checkDebugInfo(curr->list[i - 1])) {
// swap them
std::swap(curr->list[i - 1], curr->list[i]);
}
}
if (curr->list.back() != back) {
// we changed the last element, update the type
curr->finalize();
}
}
};
//
// Asm2WasmBuilder - converts an asm.js module into WebAssembly
//
class Asm2WasmBuilder {
public:
Module& wasm;
MixedArena& allocator;
Builder builder;
std::unique_ptr<OptimizingIncrementalModuleBuilder> optimizingBuilder;
// globals
struct MappedGlobal {
Type type;
// if true, this is an import - we should read the value, not just set a
// zero
bool import;
IString module, base;
MappedGlobal() : type(Type::none), import(false) {}
MappedGlobal(Type type) : type(type), import(false) {}
MappedGlobal(Type type, bool import, IString module, IString base)
: type(type), import(import), module(module), base(base) {}
};
// function table
// each asm function table gets a range in the one wasm table, starting at a
// location
std::map<IString, int> functionTableStarts;
Asm2WasmPreProcessor& preprocessor;
bool debug;
TrapMode trapMode;
TrappingFunctionContainer trappingFunctions;
PassOptions passOptions;
bool legalizeJavaScriptFFI;
bool runOptimizationPasses;
bool wasmOnly;
public:
std::map<IString, MappedGlobal> mappedGlobals;
private:
void allocateGlobal(IString name, Type type, Literal value = Literal()) {
assert(mappedGlobals.find(name) == mappedGlobals.end());
if (value.type == Type::none) {
value = Literal::makeZero(type);
}
mappedGlobals.emplace(name, MappedGlobal(type));
wasm.addGlobal(builder.makeGlobal(
name, type, builder.makeConst(value), Builder::Mutable));
}
struct View {
unsigned bytes;
bool integer, signed_;
AsmType type;
View() : bytes(0) {}
View(unsigned bytes, bool integer, bool signed_, AsmType type)
: bytes(bytes), integer(integer), signed_(signed_), type(type) {}
};
std::map<IString, View> views; // name (e.g. HEAP8) => view info
// Imported names of Math.*
IString Math_imul;
IString Math_clz32;
IString Math_fround;
IString Math_abs;
IString Math_floor;
IString Math_ceil;
IString Math_sqrt;
IString Math_max;
IString Math_min;
// Imported names of Atomics.*
IString Atomics_load;
IString Atomics_store;
IString Atomics_exchange;
IString Atomics_compareExchange;
IString Atomics_add;
IString Atomics_sub;
IString Atomics_and;
IString Atomics_or;
IString Atomics_xor;
IString llvm_cttz_i32;
IString tempDoublePtr; // imported name of tempDoublePtr
// possibly-minified names, detected via their exports
IString udivmoddi4;
IString getTempRet0;
// function types. we fill in this information as we see
// uses, in the first pass
std::map<IString, Signature> importedSignatures;
void noteImportedFunctionCall(Ref ast, Type resultType, Call* call) {
assert(ast[0] == CALL && ast[1]->isString());
IString importName = ast[1]->getIString();
std::vector<Type> params;
for (auto* operand : call->operands) {
params.push_back(operand->type);
}
Signature sig = Signature(Type(params), resultType);
// if we already saw this signature, verify it's the same (or else handle
// that)
if (importedSignatures.find(importName) != importedSignatures.end()) {
Signature& previous = importedSignatures[importName];
if (sig != previous) {
std::vector<Type> mergedParams = previous.params.expand();
// merge it in. we'll add on extra 0 parameters for ones not actually
// used, and upgrade types to double where there is a conflict (which is
// ok since in JS, double can contain everything i32 and f32 can).
for (size_t i = 0; i < params.size(); i++) {
if (mergedParams.size() > i) {
if (mergedParams[i] != params[i]) {
mergedParams[i] = Type::f64; // overloaded type, make it a double
}
} else {
mergedParams.push_back(params[i]); // add a new param
}
}
previous.params = Type(mergedParams);
// we accept none and a concrete type, but two concrete types mean we
// need to use an f64 to contain anything
if (previous.results == Type::none) {
previous.results = sig.results; // use a more concrete type
} else if (previous.results != sig.results &&
sig.results != Type::none) {
// overloaded return type, make it a double
previous.results = Type::f64;
}
}
} else {
importedSignatures[importName] = sig;
}
}
Type getResultTypeOfCallUsingParent(Ref parent, AsmData* data) {
Type result = Type::none;
if (!!parent) {
// if the parent is a seq, we cannot be the last element in it (we would
// have a coercion, which would be the parent), so we must be (us,
// somethingElse), and so our return is void
if (parent[0] != SEQ) {
result = detectWasmType(parent, data);
}
}
return result;
}
Signature getSignature(Ref parent, ExpressionList& operands, AsmData* data) {
Type results = getResultTypeOfCallUsingParent(parent, data);
std::vector<Type> paramTypes;
for (auto& op : operands) {
assert(op->type != Type::unreachable);
paramTypes.push_back(op->type);
}
return Signature(Type(paramTypes), results);
}
public:
Asm2WasmBuilder(Module& wasm,
Asm2WasmPreProcessor& preprocessor,
bool debug,
TrapMode trapMode,
PassOptions passOptions,
bool legalizeJavaScriptFFI,
bool runOptimizationPasses,
bool wasmOnly)
: wasm(wasm), allocator(wasm.allocator), builder(wasm),
preprocessor(preprocessor), debug(debug), trapMode(trapMode),
trappingFunctions(trapMode, wasm, /* immediate = */ true),
passOptions(passOptions), legalizeJavaScriptFFI(legalizeJavaScriptFFI),
runOptimizationPasses(runOptimizationPasses), wasmOnly(wasmOnly) {}
void processAsm(Ref ast);
private:
AsmType detectAsmType(Ref ast, AsmData* data) {
if (ast->isString()) {
IString name = ast->getIString();
if (!data->isLocal(name)) {
// must be global
assert(mappedGlobals.find(name) != mappedGlobals.end());
return wasmToAsmType(mappedGlobals[name].type);
}
} else if (ast->isArray(SUB) && ast[1]->isString()) {
// could be a heap access, use view info
auto view = views.find(ast[1]->getIString());
if (view != views.end()) {
return view->second.type;
}
}
return detectType(ast, data, false, Math_fround, wasmOnly);
}
Type detectWasmType(Ref ast, AsmData* data) {
return asmToWasmType(detectAsmType(ast, data));
}
bool isUnsignedCoercion(Ref ast) {
return detectSign(ast, Math_fround) == ASM_UNSIGNED;
}
bool isParentUnsignedCoercion(Ref parent) {
// parent may not exist, or may be a non-relevant node
if (!!parent && parent->isArray() && parent[0] == BINARY &&
isUnsignedCoercion(parent)) {
return true;
}
return false;
}
BinaryOp parseAsmBinaryOp(IString op,
Ref left,
Ref right,
Expression* leftWasm,
Expression* rightWasm) {
Type leftType = leftWasm->type;
bool isInteger = leftType == Type::i32;
if (op == PLUS) {
return isInteger ? BinaryOp::AddInt32
: (leftType == Type::f32 ? BinaryOp::AddFloat32
: BinaryOp::AddFloat64);
}
if (op == MINUS) {
return isInteger ? BinaryOp::SubInt32
: (leftType == Type::f32 ? BinaryOp::SubFloat32
: BinaryOp::SubFloat64);
}
if (op == MUL) {
return isInteger ? BinaryOp::MulInt32
: (leftType == Type::f32 ? BinaryOp::MulFloat32
: BinaryOp::MulFloat64);
}
if (op == AND) {
return BinaryOp::AndInt32;
}
if (op == OR) {
return BinaryOp::OrInt32;
}
if (op == XOR) {
return BinaryOp::XorInt32;
}
if (op == LSHIFT) {
return BinaryOp::ShlInt32;
}
if (op == RSHIFT) {
return BinaryOp::ShrSInt32;
}
if (op == TRSHIFT) {
return BinaryOp::ShrUInt32;
}
if (op == EQ) {
return isInteger ? BinaryOp::EqInt32
: (leftType == Type::f32 ? BinaryOp::EqFloat32
: BinaryOp::EqFloat64);
}
if (op == NE) {
return isInteger ? BinaryOp::NeInt32
: (leftType == Type::f32 ? BinaryOp::NeFloat32
: BinaryOp::NeFloat64);
}
bool isUnsigned = isUnsignedCoercion(left) || isUnsignedCoercion(right);
if (op == DIV) {
if (isInteger) {
return isUnsigned ? BinaryOp::DivUInt32 : BinaryOp::DivSInt32;
}
return leftType == Type::f32 ? BinaryOp::DivFloat32
: BinaryOp::DivFloat64;
}
if (op == MOD) {
if (isInteger) {
return isUnsigned ? BinaryOp::RemUInt32 : BinaryOp::RemSInt32;
}
return BinaryOp::RemSInt32; // XXX no floating-point remainder op, this
// must be handled by the caller
}
if (op == GE) {
if (isInteger) {
return isUnsigned ? BinaryOp::GeUInt32 : BinaryOp::GeSInt32;
}
return leftType == Type::f32 ? BinaryOp::GeFloat32 : BinaryOp::GeFloat64;
}
if (op == GT) {
if (isInteger) {
return isUnsigned ? BinaryOp::GtUInt32 : BinaryOp::GtSInt32;
}
return leftType == Type::f32 ? BinaryOp::GtFloat32 : BinaryOp::GtFloat64;
}
if (op == LE) {
if (isInteger) {
return isUnsigned ? BinaryOp::LeUInt32 : BinaryOp::LeSInt32;
}
return leftType == Type::f32 ? BinaryOp::LeFloat32 : BinaryOp::LeFloat64;
}
if (op == LT) {
if (isInteger) {
return isUnsigned ? BinaryOp::LtUInt32 : BinaryOp::LtSInt32;
}
return leftType == Type::f32 ? BinaryOp::LtFloat32 : BinaryOp::LtFloat64;
}
abort_on("bad wasm binary op", op);
abort(); // avoid warning
}
int32_t bytesToShift(unsigned bytes) {
switch (bytes) {
case 1:
return 0;
case 2:
return 1;
case 4:
return 2;
case 8:
return 3;
default: {}
}
abort();
return -1; // avoid warning
}
std::map<unsigned, Ref> tempNums;
Literal checkLiteral(Ref ast, bool rawIsInteger = true) {
if (ast->isNumber()) {
if (rawIsInteger) {
return Literal((int32_t)ast->getInteger());
} else {
return Literal(ast->getNumber());
}
} else if (ast->isArray(UNARY_PREFIX)) {
if (ast[1] == PLUS && ast[2]->isNumber()) {
return Literal((double)ast[2]->getNumber());
}
if (ast[1] == MINUS && ast[2]->isNumber()) {
double num = -ast[2]->getNumber();
if (isSInteger32(num)) {
return Literal((int32_t)num);
}
if (isUInteger32(num)) {
return Literal((uint32_t)num);
}
assert(false && "expected signed or unsigned int32");
}
if (ast[1] == PLUS && ast[2]->isArray(UNARY_PREFIX) &&
ast[2][1] == MINUS && ast[2][2]->isNumber()) {
return Literal((double)-ast[2][2]->getNumber());
}
if (ast[1] == MINUS && ast[2]->isArray(UNARY_PREFIX) &&
ast[2][1] == PLUS && ast[2][2]->isNumber()) {
return Literal((double)-ast[2][2]->getNumber());
}
} else if (wasmOnly && ast->isArray(CALL) && ast[1]->isString() &&
ast[1] == I64_CONST) {
uint64_t low = ast[2][0]->getNumber();
uint64_t high = ast[2][1]->getNumber();
return Literal(uint64_t(low + (high << 32)));
}
return Literal();
}
Literal getLiteral(Ref ast) {
Literal ret = checkLiteral(ast);
assert(ret.type != Type::none);
return ret;
}
void fixCallType(Expression* call, Type type) {
if (call->is<Call>()) {
call->cast<Call>()->type = type;
} else if (call->is<CallIndirect>()) {
call->cast<CallIndirect>()->type = type;
}
}
bool getBuiltinSignature(Signature& sig,
Name module,
Name base,
ExpressionList* operands = nullptr) {
if (module == GLOBAL_MATH) {
if (base == ABS) {
assert(operands && operands->size() == 1);
Type type = (*operands)[0]->type;
if (type == Type::i32) {
sig = Signature(Type::i32, Type::i32);
return true;
}
if (type == Type::f32) {
sig = Signature(Type::f32, Type::f32);
return true;
}
if (type == Type::f64) {
sig = Signature(Type::f64, Type::f64);
return true;
}
}
}
return false;
}
// ensure a nameless block
Block* blockify(Expression* expression) {
if (expression->is<Block>() && !expression->cast<Block>()->name.is()) {
return expression->dynCast<Block>();
}
auto ret = allocator.alloc<Block>();
ret->list.push_back(expression);
ret->finalize();
return ret;
}
Expression* ensureDouble(Expression* expr) {
return wasm::ensureDouble(expr, allocator);
}
Expression* truncateToInt32(Expression* value) {
if (value->type == Type::i64) {
return builder.makeUnary(UnaryOp::WrapInt64, value);
}
// either i32, or a call_import whose type we don't know yet (but would be
// legalized to i32 anyhow)
return value;
}
Function* processFunction(Ref ast);
};
void Asm2WasmBuilder::processAsm(Ref ast) {
assert(ast[0] == TOPLEVEL);
if (ast[1]->size() == 0) {
Fatal() << "empty input";
}
Ref asmFunction = ast[1][0];
assert(asmFunction[0] == DEFUN);
Ref body = asmFunction[3];
assert(body[0][0] == STRING &&
(body[0][1]->getIString() == IString("use asm") ||
body[0][1]->getIString() == IString("almost asm")));
// extra functions that we add, that are not from the compiled code. we need
// to make sure to optimize them normally (OptimizingIncrementalModuleBuilder
// does that on the fly for compiled code)
std::vector<Function*> extraSupportFunctions;
// first, add the memory elements. we do this before the main compile+optimize
// since the optimizer should see the memory
// apply memory growth, if relevant
if (preprocessor.memoryGrowth) {
EmscriptenGlueGenerator generator(wasm);
auto* func = generator.generateMemoryGrowthFunction();
extraSupportFunctions.push_back(func);
wasm.memory.max = Memory::kUnlimitedSize;
}
// import memory
wasm.memory.name = MEMORY;
wasm.memory.module = ENV;
wasm.memory.base = MEMORY;
wasm.memory.exists = true;
// import table
wasm.table.name = TABLE;
wasm.table.module = ENV;
wasm.table.base = TABLE;
wasm.table.exists = true;
// Import memory offset, if not already there
{
auto* import = new Global;
import->name = MEMORY_BASE;
import->module = "env";
import->base = MEMORY_BASE;
import->type = Type::i32;
wasm.addGlobal(import);
}
// Import table offset, if not already there
{
auto* import = new Global;
import->name = TABLE_BASE;
import->module = "env";
import->base = TABLE_BASE;
import->type = Type::i32;
wasm.addGlobal(import);
}
auto addImport = [&](IString name, Ref imported, Type type) {
assert(imported[0] == DOT);
Ref module = imported[1];
IString moduleName;
if (module->isArray(DOT)) {
// we can have (global.Math).floor; skip the 'Math'
assert(module[1]->isString());
if (module[2] == MATH) {
if (imported[2] == IMUL) {
assert(Math_imul.isNull());
Math_imul = name;
return;
} else if (imported[2] == CLZ32) {
assert(Math_clz32.isNull());
Math_clz32 = name;
return;
} else if (imported[2] == FROUND) {
assert(Math_fround.isNull());
Math_fround = name;
return;
} else if (imported[2] == ABS) {
assert(Math_abs.isNull());
Math_abs = name;
return;
} else if (imported[2] == FLOOR) {
assert(Math_floor.isNull());
Math_floor = name;
return;
} else if (imported[2] == CEIL) {
assert(Math_ceil.isNull());
Math_ceil = name;
return;
} else if (imported[2] == SQRT) {
assert(Math_sqrt.isNull());
Math_sqrt = name;
return;
} else if (imported[2] == MAX_) {
assert(Math_max.isNull());
Math_max = name;
return;
} else if (imported[2] == MIN_) {
assert(Math_min.isNull());
Math_min = name;
return;
}
} else if (module[2] == ATOMICS) {
if (imported[2] == ATOMICS_LOAD) {
assert(Atomics_load.isNull());
Atomics_load = name;
return;
} else if (imported[2] == ATOMICS_STORE) {
assert(Atomics_store.isNull());
Atomics_store = name;
return;
} else if (imported[2] == ATOMICS_EXCHANGE) {
assert(Atomics_exchange.isNull());
Atomics_exchange = name;
return;
} else if (imported[2] == ATOMICS_COMPARE_EXCHANGE) {
assert(Atomics_compareExchange.isNull());
Atomics_compareExchange = name;
return;
} else if (imported[2] == ATOMICS_ADD) {
assert(Atomics_add.isNull());
Atomics_add = name;
return;
} else if (imported[2] == ATOMICS_SUB) {
assert(Atomics_sub.isNull());
Atomics_sub = name;
return;
} else if (imported[2] == ATOMICS_AND) {
assert(Atomics_and.isNull());
Atomics_and = name;
return;
} else if (imported[2] == ATOMICS_OR) {
assert(Atomics_or.isNull());
Atomics_or = name;
return;
} else if (imported[2] == ATOMICS_XOR) {
assert(Atomics_xor.isNull());
Atomics_xor = name;
return;
}
}
std::string fullName = module[1]->getCString();
fullName += '.';
fullName += +module[2]->getCString();
moduleName = IString(fullName.c_str(), false);
} else {
assert(module->isString());
moduleName = module->getIString();
if (moduleName == ENV) {
auto base = imported[2]->getIString();
if (base == TEMP_DOUBLE_PTR) {
assert(tempDoublePtr.isNull());
tempDoublePtr = name;
// we don't return here, as we can only optimize out some uses of tDP.
// So it remains imported
} else if (base == LLVM_CTTZ_I32) {
assert(llvm_cttz_i32.isNull());
llvm_cttz_i32 = name;
return;
}
}
}
auto base = imported[2]->getIString();
// special-case some asm builtins
if (module == GLOBAL && (base == NAN_ || base == INFINITY_)) {
type = Type::f64;
}
if (type != Type::none) {
// this is a global
auto* import = new Global;
import->name = name;
import->module = moduleName;
import->base = base;
import->type = type;
mappedGlobals.emplace(name, type);
// __table_base and __memory_base are used as segment/element offsets, and
// must be constant; otherwise, an asm.js import of a constant is mutable,
// e.g. STACKTOP
if (name != TABLE_BASE && name != MEMORY_BASE) {
// we need imported globals to be mutable, but wasm doesn't support that
// yet, so we must import an immutable and create a mutable global
// initialized to its value
import->name = Name(std::string(import->name.str) + "$asm2wasm$import");
{
wasm.addGlobal(
builder.makeGlobal(name,
type,
builder.makeGlobalGet(import->name, type),
Builder::Mutable));
}
}
if ((name == TABLE_BASE || name == MEMORY_BASE) &&
wasm.getGlobalOrNull(import->base)) {
return;
}
wasm.addGlobal(import);
} else {
// this is a function
auto* import = new Function;
import->name = name;
import->module = moduleName;
import->base = base;
import->sig = Signature(Type::none, Type::none);
wasm.addFunction(import);
}
};
IString Int8Array, Int16Array, Int32Array, UInt8Array, UInt16Array,
UInt32Array, Float32Array, Float64Array;
// set up optimization
if (runOptimizationPasses) {
Index numFunctions = 0;
for (unsigned i = 1; i < body->size(); i++) {
if (body[i][0] == DEFUN) {
numFunctions++;
}
}
optimizingBuilder = make_unique<OptimizingIncrementalModuleBuilder>(
&wasm,
numFunctions,
passOptions,
[&](PassRunner& passRunner) {
// addPrePasses
passRunner.options.lowMemoryUnused = true;
if (debug) {
passRunner.setDebug(true);
passRunner.setValidateGlobally(false);
}
// run autodrop first, before optimizations
passRunner.add(make_unique<AutoDrop>());
if (preprocessor.debugInfo) {
// fix up debug info to better survive optimization
passRunner.add(make_unique<AdjustDebugInfo>());
}
// optimize relooper label variable usage at the wasm level, where it is
// easy
passRunner.add("relooper-jump-threading");
},
debug,
false /* do not validate globally yet */);
}
// if we see no function tables in the processing below, then the table still
// exists and has size 0
wasm.table.initial = wasm.table.max = 0;
// first pass - do all global things, aside from function bodies (second pass)
// and function imports and indirect calls (last pass)
for (unsigned i = 1; i < body->size(); i++) {
Ref curr = body[i];
if (curr[0] == VAR) {
// import, global, or table
for (unsigned j = 0; j < curr[1]->size(); j++) {
Ref pair = curr[1][j];
IString name = pair[0]->getIString();
Ref value = pair[1];
if (value->isNumber()) {
// global int
allocateGlobal(
name, Type::i32, Literal(int32_t(value->getInteger())));
} else if (value[0] == BINARY) {
// int import
assert(value[1] == OR && value[3]->isNumber() &&
value[3]->getNumber() == 0);
Ref import = value[2]; // env.what
addImport(name, import, Type::i32);
} else if (value[0] == UNARY_PREFIX) {
// double import or global
assert(value[1] == PLUS);
Ref import = value[2];
if (import->isNumber()) {
// global
assert(import->getNumber() == 0);
allocateGlobal(name, Type::f64);
} else {
// import
addImport(name, import, Type::f64);
}
} else if (value[0] == CALL) {
assert(value[1]->isString() && value[1] == Math_fround &&
value[2][0]->isNumber() && value[2][0]->getNumber() == 0);
allocateGlobal(name, Type::f32);
} else if (value[0] == DOT) {
// simple module.base import. can be a view, or a function.
if (value[1]->isString()) {
IString module = value[1]->getIString();
IString base = value[2]->getIString();
if (module == GLOBAL) {
if (base == INT8ARRAY) {
Int8Array = name;
} else if (base == INT16ARRAY) {
Int16Array = name;
} else if (base == INT32ARRAY) {
Int32Array = name;
} else if (base == UINT8ARRAY) {
UInt8Array = name;
} else if (base == UINT16ARRAY) {
UInt16Array = name;
} else if (base == UINT32ARRAY) {
UInt32Array = name;
} else if (base == FLOAT32ARRAY) {
Float32Array = name;
} else if (base == FLOAT64ARRAY) {
Float64Array = name;
}
}
}
// function import
addImport(name, value, Type::none);
} else if (value[0] == NEW) {
// ignore imports of typed arrays, but note the names of the arrays
value = value[1];
assert(value[0] == CALL);
unsigned bytes;
bool integer, signed_;
AsmType asmType;
Ref constructor = value[1];
if (constructor->isArray(DOT)) { // global.*Array
IString heap = constructor[2]->getIString();
if (heap == INT8ARRAY) {
bytes = 1;
integer = true;
signed_ = true;
asmType = ASM_INT;
} else if (heap == INT16ARRAY) {
bytes = 2;
integer = true;
signed_ = true;
asmType = ASM_INT;
} else if (heap == INT32ARRAY) {
bytes = 4;
integer = true;
signed_ = true;
asmType = ASM_INT;
} else if (heap == UINT8ARRAY) {
bytes = 1;
integer = true;
signed_ = false;
asmType = ASM_INT;
} else if (heap == UINT16ARRAY) {
bytes = 2;
integer = true;
signed_ = false;
asmType = ASM_INT;
} else if (heap == UINT32ARRAY) {
bytes = 4;
integer = true;
signed_ = false;
asmType = ASM_INT;
} else if (heap == FLOAT32ARRAY) {
bytes = 4;
integer = false;
signed_ = true;
asmType = ASM_FLOAT;
} else if (heap == FLOAT64ARRAY) {
bytes = 8;
integer = false;
signed_ = true;
asmType = ASM_DOUBLE;
} else {
abort_on("invalid view import", heap);
}
} else { // *ArrayView that was previously imported
assert(constructor->isString());
IString viewName = constructor->getIString();
if (viewName == Int8Array) {
bytes = 1;
integer = true;
signed_ = true;
asmType = ASM_INT;
} else if (viewName == Int16Array) {
bytes = 2;
integer = true;
signed_ = true;
asmType = ASM_INT;
} else if (viewName == Int32Array) {
bytes = 4;
integer = true;
signed_ = true;
asmType = ASM_INT;
} else if (viewName == UInt8Array) {
bytes = 1;
integer = true;
signed_ = false;
asmType = ASM_INT;
} else if (viewName == UInt16Array) {
bytes = 2;
integer = true;
signed_ = false;
asmType = ASM_INT;
} else if (viewName == UInt32Array) {
bytes = 4;
integer = true;
signed_ = false;
asmType = ASM_INT;
} else if (viewName == Float32Array) {
bytes = 4;
integer = false;
signed_ = true;
asmType = ASM_FLOAT;
} else if (viewName == Float64Array) {
bytes = 8;
integer = false;
signed_ = true;
asmType = ASM_DOUBLE;
} else {
abort_on("invalid short view import", viewName);
}
}
assert(views.find(name) == views.end());
views.emplace(name, View(bytes, integer, signed_, asmType));
} else if (value[0] == ARRAY) {
// function table. we merge them into one big table, so e.g. [foo,
// b1] , [b2, bar] => [foo, b1, b2, bar]
// TODO: when not using aliasing function pointers, we could merge
// them by noticing that
// index 0 in each table is the null func, and each other index
// should only have one non-null func. However, that breaks down
// when function pointer casts are emulated.
if (wasm.table.segments.size() == 0) {
wasm.table.segments.emplace_back(
builder.makeGlobalGet(Name(TABLE_BASE), Type::i32));
}
auto& segment = wasm.table.segments[0];
functionTableStarts[name] =
segment.data.size(); // this table starts here
Ref contents = value[1];
for (unsigned k = 0; k < contents->size(); k++) {
IString curr = contents[k]->getIString();
segment.data.push_back(curr);
}
wasm.table.initial = wasm.table.max = segment.data.size();
} else {
abort_on("invalid var element", pair);
}
}
} else if (curr[0] == RETURN) {
// exports
Ref object = curr[1];
Ref contents = object[1];
std::map<Name, Export*> exported;
for (unsigned k = 0; k < contents->size(); k++) {
Ref pair = contents[k];
IString key = pair[0]->getIString();
if (pair[1]->isString()) {
// exporting a function
IString value = pair[1]->getIString();
if (key == Name("_emscripten_replace_memory")) {
// asm.js memory growth provides this special non-asm function,
// which we don't need (we use memory.grow)
assert(!wasm.getFunctionOrNull(value));
continue;
} else if (key == UDIVMODDI4) {
udivmoddi4 = value;
} else if (key == GET_TEMP_RET0) {
getTempRet0 = value;
}
if (exported.count(key) > 0) {
// asm.js allows duplicate exports, but not wasm. use the last, like
// asm.js
exported[key]->value = value;
} else {
auto* export_ = new Export;
export_->name = key;
export_->value = value;
export_->kind = ExternalKind::Function;
wasm.addExport(export_);
exported[key] = export_;
}
} else {
// export a number. create a global and export it
assert(pair[1]->isNumber());
assert(exported.count(key) == 0);
auto value = pair[1]->getInteger();
auto* global =
builder.makeGlobal(key,
Type::i32,
builder.makeConst(Literal(int32_t(value))),
Builder::Immutable);
wasm.addGlobal(global);
auto* export_ = new Export;
export_->name = key;
export_->value = global->name;
export_->kind = ExternalKind::Global;
wasm.addExport(export_);
exported[key] = export_;
}
}
}
}
// second pass: function bodies
for (unsigned i = 1; i < body->size(); i++) {
Ref curr = body[i];
if (curr[0] == DEFUN) {
// function
auto* func = processFunction(curr);
if (wasm.getFunctionOrNull(func->name)) {
Fatal() << "duplicate function: " << func->name;
}
if (runOptimizationPasses) {
optimizingBuilder->addFunction(func);
} else {
wasm.addFunction(func);
}
}
}
if (runOptimizationPasses) {
optimizingBuilder->finish();
// Now that we have a full module, do memory packing optimizations
{
PassRunner passRunner(&wasm, passOptions);
passRunner.options.lowMemoryUnused = true;
passRunner.add("memory-packing");
passRunner.run();
}
// if we added any helper functions (like non-trapping i32-div, etc.), then
// those have not been optimized (the optimizing builder has just been fed
// the asm.js functions). Optimize those now. Typically there are very few,
// just do it sequentially.
PassRunner passRunner(&wasm, passOptions);
passRunner.options.lowMemoryUnused = true;
passRunner.addDefaultFunctionOptimizationPasses();
for (auto& pair : trappingFunctions.getFunctions()) {
auto* func = pair.second;
passRunner.runOnFunction(func);
}
for (auto* func : extraSupportFunctions) {
passRunner.runOnFunction(func);
}
}
wasm.debugInfoFileNames = std::move(preprocessor.debugInfoFileNames);
// third pass. first, function imports
std::vector<IString> toErase;
ModuleUtils::iterImportedFunctions(wasm, [&](Function* import) {
IString name = import->name;
if (importedSignatures.find(name) != importedSignatures.end()) {
// special math builtins
Signature builtin;
if (getBuiltinSignature(builtin, import->module, import->base)) {
import->sig = builtin;
} else {
import->sig = importedSignatures[name];
}
} else if (import->module != ASM2WASM) { // special-case the special module
// never actually used, which means we don't know the function type since
// the usage tells us, so illegal for it to remain
toErase.push_back(name);
}
});
for (auto curr : toErase) {
wasm.removeFunction(curr);
}
// Finalize calls now that everything is known and generated
struct FinalizeCalls : public WalkerPass<PostWalker<FinalizeCalls>> {
bool isFunctionParallel() override { return true; }
Pass* create() override { return new FinalizeCalls(parent); }
Asm2WasmBuilder* parent;
FinalizeCalls(Asm2WasmBuilder* parent) : parent(parent) {
name = "finalize-calls";
}
void notifyAboutWrongOperands(std::string why, Function* calledFunc) {
// use a mutex as this may be shown from multiple threads
static std::mutex mutex;
std::unique_lock<std::mutex> lock(mutex);
static const int MAX_SHOWN = 20;
static std::unique_ptr<std::atomic<int>> numShown;
if (!numShown) {
numShown = make_unique<std::atomic<int>>();
numShown->store(0);
}
if (numShown->load() >= MAX_SHOWN) {
return;
}
std::cerr << why << " in call from " << getFunction()->name << " to "
<< calledFunc->name
<< " (this is likely due to undefined behavior in C, like "
"defining a function one way and calling it in another, "
"which is important to fix)\n";
(*numShown)++;
if (numShown->load() >= MAX_SHOWN) {
std::cerr << "(" << numShown->load()
<< " such warnings shown; not showing any more)\n";
}
}
void visitCall(Call* curr) {
// The call target may not exist if it is one of our special fake imports
// for callIndirect fixups
auto* calledFunc = getModule()->getFunctionOrNull(curr->target);
if (calledFunc && !calledFunc->imported()) {
// The result type of the function being called is now known, and can be
// applied.
auto results = calledFunc->sig.results;
if (curr->type != results) {
curr->type = results;
}
// Handle mismatched numbers of arguments. In clang, if a function is
// declared one way but called in another, it inserts bitcasts to make
// things work. Those end up working since it is "ok" to drop or add
// parameters in native platforms, even though it's undefined behavior.
// We warn about it here, but tolerate it, if there is a simple
// solution.
const std::vector<Type>& params = calledFunc->sig.params.expand();
if (curr->operands.size() < params.size()) {
notifyAboutWrongOperands("warning: asm2wasm adding operands",
calledFunc);
while (curr->operands.size() < params.size()) {
// Add params as necessary, with zeros.
curr->operands.push_back(LiteralUtils::makeZero(
params[curr->operands.size()], *getModule()));
}
}
if (curr->operands.size() > params.size()) {
notifyAboutWrongOperands("warning: asm2wasm dropping operands",
calledFunc);
curr->operands.resize(params.size());
}
// If the types are wrong, validation will fail later anyhow, but add a
// warning here, it may help people.
for (Index i = 0; i < curr->operands.size(); i++) {
auto sent = curr->operands[i]->type;
if (sent != Type::unreachable && sent != params[i]) {
notifyAboutWrongOperands(
"error: asm2wasm seeing an invalid argument type at index " +
std::to_string(i) + " (this will not validate)",
calledFunc);
}
}
} else {
// A call to an import
// fill things out: add extra params as needed, etc. asm tolerates ffi
// overloading, wasm does not
auto iter = parent->importedSignatures.find(curr->target);
if (iter == parent->importedSignatures.end()) {
return; // one of our fake imports for callIndirect fixups
}
const std::vector<Type>& params = iter->second.params.expand();
for (size_t i = 0; i < params.size(); i++) {
if (i >= curr->operands.size()) {
// add a new param
auto val = parent->allocator.alloc<Const>();
val->type = val->value.type = params[i];
curr->operands.push_back(val);
} else if (curr->operands[i]->type != params[i]) {
// if the param is used, then we have overloading here and the
// combined type must be f64; if this is an unreachable param, then
// it doesn't matter.
assert(params[i] == Type::f64 ||
curr->operands[i]->type == Type::unreachable);
// overloaded, upgrade to f64
switch (curr->operands[i]->type.getSingle()) {
case Type::i32:
curr->operands[i] = parent->builder.makeUnary(
ConvertSInt32ToFloat64, curr->operands[i]);
break;
case Type::f32:
curr->operands[i] =
parent->builder.makeUnary(PromoteFloat32, curr->operands[i]);
break;
default: {} // f64, unreachable, etc., are all good
}
}
}
Module* wasm = getModule();
Type importResults = wasm->getFunction(curr->target)->sig.results;
if (curr->type != importResults) {
auto old = curr->type;
curr->type = importResults;
if (importResults == Type::f64) {
// we use a JS f64 value which is the most general, and convert to
// it
switch (old.getSingle()) {
case Type::i32: {
Unary* trunc =
parent->builder.makeUnary(TruncSFloat64ToInt32, curr);
replaceCurrent(
makeTrappingUnary(trunc, parent->trappingFunctions));
break;
}
case Type::f32: {
replaceCurrent(parent->builder.makeUnary(DemoteFloat64, curr));
break;
}
case Type::none: {
// this function returns a value, but we are not using it, so it
// must be dropped. autodrop will do that for us.
break;
}
default:
WASM_UNREACHABLE("unexpected type");
}
} else {
assert(old == Type::none);
// we don't want a return value here, but the import does provide
// one autodrop will do that for us.
}
}
}
}
void visitCallIndirect(CallIndirect* curr) {
// we already call into target = something + offset, where offset is a
// callImport with the name of the table. replace that with the table
// offset note that for an ftCall or mftCall, we have no asm.js mask, so
// have nothing to do here
auto* target = curr->target;
// might be a block with a fallthrough
if (auto* block = target->dynCast<Block>()) {
target = block->list.back();
}
// the something might have been optimized out, leaving only the call
if (auto* call = target->dynCast<Call>()) {
auto tableName = call->target;
if (parent->functionTableStarts.find(tableName) ==
parent->functionTableStarts.end()) {
return;
}
curr->target = parent->builder.makeConst(
Literal((int32_t)parent->functionTableStarts[tableName]));
return;
}
auto* add = target->dynCast<Binary>();
if (!add) {
return;
}
if (add->right->is<Call>()) {
auto* offset = add->right->cast<Call>();
auto tableName = offset->target;
if (parent->functionTableStarts.find(tableName) ==
parent->functionTableStarts.end()) {
return;
}
add->right = parent->builder.makeConst(
Literal((int32_t)parent->functionTableStarts[tableName]));
} else {
auto* offset = add->left->dynCast<Call>();
if (!offset) {
return;
}
auto tableName = offset->target;
if (parent->functionTableStarts.find(tableName) ==
parent->functionTableStarts.end()) {
return;
}
add->left = parent->builder.makeConst(
Literal((int32_t)parent->functionTableStarts[tableName]));
}
}
void visitFunction(Function* curr) {
// changing call types requires we percolate types, and drop stuff.
// we do this in this pass so that we don't look broken between passes
AutoDrop().walkFunctionInModule(curr, getModule());
}
};
// apply debug info, reducing intrinsic calls into annotations on the ast
// nodes
struct ApplyDebugInfo
: public WalkerPass<
ExpressionStackWalker<ApplyDebugInfo,
UnifiedExpressionVisitor<ApplyDebugInfo>>> {
bool isFunctionParallel() override { return true; }
Pass* create() override { return new ApplyDebugInfo(); }
ApplyDebugInfo() { name = "apply-debug-info"; }
Call* lastDebugInfo = nullptr;
void visitExpression(Expression* curr) {
if (auto* call = checkDebugInfo(curr)) {
lastDebugInfo = call;
replaceCurrent(getModule()->allocator.alloc<Nop>());
} else {
if (lastDebugInfo) {
auto& debugLocations = getFunction()->debugLocations;
uint32_t fileIndex =
lastDebugInfo->operands[0]->cast<Const>()->value.geti32();
assert(getModule()->debugInfoFileNames.size() > fileIndex);
uint32_t lineNumber =
lastDebugInfo->operands[1]->cast<Const>()->value.geti32();
// look up the stack, apply to the root expression
Index i = expressionStack.size() - 1;
while (1) {
auto* exp = expressionStack[i];
bool parentIsStructure =
i > 0 && (expressionStack[i - 1]->is<Block>() ||
expressionStack[i - 1]->is<Loop>() ||
expressionStack[i - 1]->is<If>());
if (i == 0 || parentIsStructure || exp->type == Type::none ||
exp->type == Type::unreachable) {
if (debugLocations.count(exp) > 0) {
// already present, so look back up
i++;
while (i < expressionStack.size()) {
exp = expressionStack[i];
if (debugLocations.count(exp) == 0) {
debugLocations[exp] = {fileIndex, lineNumber, 0};
break;
}
i++;
}
} else {
debugLocations[exp] = {fileIndex, lineNumber, 0};
}
break;
}
i--;
}
lastDebugInfo = nullptr;
}
}
}
};
PassRunner passRunner(&wasm, passOptions);
passRunner.options.lowMemoryUnused = true;
if (debug) {
passRunner.setDebug(true);
passRunner.setValidateGlobally(false);
}
// finalizeCalls also does autoDrop, which is crucial for the non-optimizing
// case, so that the output of the first pass is valid
passRunner.add(make_unique<FinalizeCalls>(this));
passRunner.add(ABI::getLegalizationPass(legalizeJavaScriptFFI
? ABI::LegalizationLevel::Full
: ABI::LegalizationLevel::Minimal));
if (runOptimizationPasses) {
// autodrop can add some garbage
passRunner.add("vacuum");
passRunner.add("remove-unused-brs");
passRunner.add("vacuum");
passRunner.add("remove-unused-names");
passRunner.add("merge-blocks");
passRunner.add("optimize-instructions");
passRunner.add("post-emscripten");
} else {
if (preprocessor.debugInfo) {
// we would have run this before if optimizing, do it now otherwise. must
// precede ApplyDebugInfo
passRunner.add(make_unique<AdjustDebugInfo>());
}
}
if (preprocessor.debugInfo) {
passRunner.add(make_unique<ApplyDebugInfo>());
// FIXME maybe just remove the nops that were debuginfo nodes, if not
// optimizing?
passRunner.add("vacuum");
}
if (runOptimizationPasses) {
// do final global optimizations after all function work is done
// (e.g. duplicate funcs may appear thanks to that work)
passRunner.addDefaultGlobalOptimizationPostPasses();
}
passRunner.run();
// remove the debug info intrinsic
if (preprocessor.debugInfo) {
wasm.removeFunction(EMSCRIPTEN_DEBUGINFO);
}
if (udivmoddi4.is() && getTempRet0.is()) {
// generate a wasm-optimized __udivmoddi4 method, which we can do much more
// efficiently in wasm we can only do this if we know getTempRet0 as well
// since we use it to figure out which minified global is tempRet0
// (getTempRet0 might be an import, if this is a shared module, so we can't
// optimize that case)
Name tempRet0;
{
Expression* curr = wasm.getFunction(getTempRet0)->body;
if (curr->is<Block>()) {
curr = curr->cast<Block>()->list.back();
}
if (curr->is<Return>()) {
curr = curr->cast<Return>()->value;
}
auto* get = curr->cast<GlobalGet>();
tempRet0 = get->name;
}
// udivmoddi4 receives xl, xh, yl, yl, r, and
// if r then *r = x % y
// returns x / y
auto* func = wasm.getFunction(udivmoddi4);
Builder::clearLocals(func);
Index xl = Builder::addParam(func, "xl", Type::i32),
xh = Builder::addParam(func, "xh", Type::i32),
yl = Builder::addParam(func, "yl", Type::i32),
yh = Builder::addParam(func, "yh", Type::i32),
r = Builder::addParam(func, "r", Type::i32),
x64 = Builder::addVar(func, "x64", Type::i64),
y64 = Builder::addVar(func, "y64", Type::i64);
auto* body = allocator.alloc<Block>();
body->list.push_back(
builder.makeLocalSet(x64, I64Utilities::recreateI64(builder, xl, xh)));
body->list.push_back(
builder.makeLocalSet(y64, I64Utilities::recreateI64(builder, yl, yh)));
body->list.push_back(
builder.makeIf(builder.makeLocalGet(r, Type::i32),
builder.makeStore(
8,
0,
8,
builder.makeLocalGet(r, Type::i32),
builder.makeBinary(RemUInt64,
builder.makeLocalGet(x64, Type::i64),
builder.makeLocalGet(y64, Type::i64)),
Type::i64)));
body->list.push_back(builder.makeLocalSet(
x64,
builder.makeBinary(DivUInt64,
builder.makeLocalGet(x64, Type::i64),
builder.makeLocalGet(y64, Type::i64))));
body->list.push_back(
builder.makeGlobalSet(tempRet0, I64Utilities::getI64High(builder, x64)));
body->list.push_back(I64Utilities::getI64Low(builder, x64));
body->finalize();
func->body = body;
}
}
Function* Asm2WasmBuilder::processFunction(Ref ast) {
auto name = ast[1]->getIString();
BYN_TRACE("asm2wasming func: " << ast[1]->getIString().str << '\n');
auto function = new Function;
function->sig = Signature(Type::none, Type::none);
function->name = name;
Ref params = ast[2];
Ref body = ast[3];
UniqueNameMapper nameMapper;
// given an asm.js label, returns the wasm label for breaks or continues
auto getBreakLabelName = [](IString label) {
return Name(std::string("label$break$") + label.str);
};
auto getContinueLabelName = [](IString label) {
return Name(std::string("label$continue$") + label.str);
};
IStringSet functionVariables; // params or vars
IString parentLabel; // set in LABEL, then read in WHILE/DO/SWITCH
std::vector<IString> breakStack; // where a break will go
std::vector<IString> continueStack; // where a continue will go
AsmData asmData; // need to know var and param types, for asm type detection
for (unsigned i = 0; i < params->size(); i++) {
Ref curr = body[i];
auto* assign = curr->asAssignName();
IString name = assign->target();
AsmType asmType =
detectType(assign->value(), nullptr, false, Math_fround, wasmOnly);
Builder::addParam(function, name, asmToWasmType(asmType));
functionVariables.insert(name);
asmData.addParam(name, asmType);
}
unsigned start = params->size();
while (start < body->size() && body[start]->isArray(VAR)) {
Ref curr = body[start];
for (unsigned j = 0; j < curr[1]->size(); j++) {
Ref pair = curr[1][j];
IString name = pair[0]->getIString();
AsmType asmType =
detectType(pair[1], nullptr, true, Math_fround, wasmOnly);
Builder::addVar(function, name, asmToWasmType(asmType));
functionVariables.insert(name);
asmData.addVar(name, asmType);
}
start++;
}
bool addedI32Temp = false;
auto ensureI32Temp = [&]() {
if (addedI32Temp) {
return;
}
addedI32Temp = true;
Builder::addVar(function, I32_TEMP, Type::i32);
functionVariables.insert(I32_TEMP);
asmData.addVar(I32_TEMP, ASM_INT);
};
bool seenReturn = false; // function->result is updated if we see a return
// processors
std::function<Expression*(Ref, unsigned)> processStatements;
std::function<Expression*(Ref, unsigned)> processUnshifted;
std::function<Expression*(Ref, unsigned)> processIgnoringShift;
std::function<Expression*(Ref)> process = [&](Ref ast) -> Expression* {
// TODO: only create one when we need it?
AstStackHelper astStackHelper(ast);
if (ast->isString()) {
IString name = ast->getIString();
if (functionVariables.has(name)) {
// var in scope
auto ret = allocator.alloc<LocalGet>();
ret->index = function->getLocalIndex(name);
ret->type = asmToWasmType(asmData.getType(name));
return ret;
}
if (name == DEBUGGER) {
Call* call = allocator.alloc<Call>();
call->target = DEBUGGER;
call->type = Type::none;
static bool addedImport = false;
if (!addedImport) {
addedImport = true;
auto import = new Function; // debugger = asm2wasm.debugger;
import->name = DEBUGGER;
import->module = ASM2WASM;
import->base = DEBUGGER;
import->sig = Signature(Type::none, Type::none);
wasm.addFunction(import);
}
return call;
}
// global var
assert(mappedGlobals.find(name) != mappedGlobals.end()
? true
: (std::cerr << name.str << '\n', false));
MappedGlobal& global = mappedGlobals[name];
return builder.makeGlobalGet(name, global.type);
}
if (ast->isNumber()) {
auto ret = allocator.alloc<Const>();
double num = ast->getNumber();
if (isSInteger32(num)) {
ret->value = Literal(int32_t(toSInteger32(num)));
} else if (isUInteger32(num)) {
ret->value = Literal(uint32_t(toUInteger32(num)));
} else {
ret->value = Literal(num);
}
ret->type = ret->value.type;
return ret;
}
if (ast->isAssignName()) {
auto* assign = ast->asAssignName();
IString name = assign->target();
if (functionVariables.has(name)) {
auto ret = allocator.alloc<LocalSet>();
ret->index = function->getLocalIndex(assign->target());
ret->value = process(assign->value());
ret->makeSet();
ret->finalize();
return ret;
}
// global var
if (mappedGlobals.find(name) == mappedGlobals.end()) {
Fatal() << "error: access of a non-existent global var " << name.str;
}
auto* ret = builder.makeGlobalSet(name, process(assign->value()));
// global.set does not return; if our value is trivially not used, don't
// emit a load (if nontrivially not used, opts get it later)
auto parent = astStackHelper.getParent();
if (!parent || parent->isArray(BLOCK) || parent->isArray(IF)) {
return ret;
}
return builder.makeSequence(
ret, builder.makeGlobalGet(name, ret->value->type));
}
if (ast->isAssign()) {
auto* assign = ast->asAssign();
assert(assign->target()->isArray(SUB));
Ref target = assign->target();
assert(target[1]->isString());
IString heap = target[1]->getIString();
assert(views.find(heap) != views.end());
View& view = views[heap];
auto ret = allocator.alloc<Store>();
ret->isAtomic = false;
ret->bytes = view.bytes;
ret->offset = 0;
ret->align = view.bytes;
ret->ptr = processUnshifted(target[2], view.bytes);
ret->value = process(assign->value());
ret->valueType = asmToWasmType(view.type);
ret->finalize();
if (ret->valueType != ret->value->type) {
// in asm.js we have some implicit coercions that we must do explicitly
// here
if (ret->valueType == Type::f32 && ret->value->type == Type::f64) {
auto conv = allocator.alloc<Unary>();
conv->op = DemoteFloat64;
conv->value = ret->value;
conv->type = Type::f32;
ret->value = conv;
} else if (ret->valueType == Type::f64 &&
ret->value->type == Type::f32) {
ret->value = ensureDouble(ret->value);
} else {
abort_on("bad sub[] types", ast);
}
}
return ret;
}
IString what = ast[0]->getIString();
if (what == BINARY) {
if ((ast[1] == OR || ast[1] == TRSHIFT) && ast[3]->isNumber() &&
ast[3]->getNumber() == 0) {
// just look through the ()|0 or ()>>>0 coercion
auto ret = process(ast[2]);
fixCallType(ret, Type::i32);
return ret;
}
auto ret = allocator.alloc<Binary>();
ret->left = process(ast[2]);
ret->right = process(ast[3]);
ret->op = parseAsmBinaryOp(
ast[1]->getIString(), ast[2], ast[3], ret->left, ret->right);
ret->finalize();
if (ret->op == BinaryOp::RemSInt32 && ret->type.isFloat()) {
// WebAssembly does not have floating-point remainder, we have to emit a
// call to a special import of ours
Call* call = allocator.alloc<Call>();
call->target = F64_REM;
call->operands.push_back(ensureDouble(ret->left));
call->operands.push_back(ensureDouble(ret->right));
call->type = Type::f64;
static bool addedImport = false;
if (!addedImport) {
addedImport = true;
auto import = new Function; // f64-rem = asm2wasm.f64-rem;
import->name = F64_REM;
import->module = ASM2WASM;
import->base = F64_REM;
import->sig = Signature({Type::f64, Type::f64}, Type::f64);
wasm.addFunction(import);
}
return call;
}
return makeTrappingBinary(ret, trappingFunctions);
} else if (what == SUB) {
Ref target = ast[1];
assert(target->isString());
IString heap = target->getIString();
assert(views.find(heap) != views.end());
View& view = views[heap];
auto ret = allocator.alloc<Load>();
ret->isAtomic = false;
ret->bytes = view.bytes;
ret->signed_ = view.signed_;
ret->offset = 0;
ret->align = view.bytes;
ret->ptr = processUnshifted(ast[2], view.bytes);
ret->type = Type::get(view.bytes, !view.integer);
return ret;
} else if (what == UNARY_PREFIX) {
if (ast[1] == PLUS) {
Literal literal = checkLiteral(ast);
if (literal.type != Type::none) {
return builder.makeConst(literal);
}
auto ret = process(ast[2]); // we are a +() coercion
if (ret->type == Type::i32) {
auto conv = allocator.alloc<Unary>();
conv->op = isUnsignedCoercion(ast[2]) ? ConvertUInt32ToFloat64
: ConvertSInt32ToFloat64;
conv->value = ret;
conv->type = Type::Type::f64;
return conv;
}
if (ret->type == Type::f32) {
return ensureDouble(ret);
}
fixCallType(ret, Type::f64);
return ret;
} else if (ast[1] == MINUS) {
if (ast[2]->isNumber() ||
(ast[2]->isArray(UNARY_PREFIX) && ast[2][1] == PLUS &&
ast[2][2]->isNumber())) {
auto ret = allocator.alloc<Const>();
ret->value = getLiteral(ast);
ret->type = ret->value.type;
return ret;
}
AsmType asmType = detectAsmType(ast[2], &asmData);
if (asmType == ASM_INT) {
// wasm has no unary negation for int, so do 0-
auto ret = allocator.alloc<Binary>();
ret->op = SubInt32;
ret->left = builder.makeConst(Literal((int32_t)0));
ret->right = process(ast[2]);
ret->type = Type::i32;
return ret;
}
auto ret = allocator.alloc<Unary>();
ret->value = process(ast[2]);
if (asmType == ASM_DOUBLE) {
ret->op = NegFloat64;
ret->type = Type::f64;
} else if (asmType == ASM_FLOAT) {
ret->op = NegFloat32;
ret->type = Type::f32;
} else {
WASM_UNREACHABLE("unexpected asm type");
}
return ret;
} else if (ast[1] == B_NOT) {
// ~, might be ~~ as a coercion or just a not
if (ast[2]->isArray(UNARY_PREFIX) && ast[2][1] == B_NOT) {
// if we have an unsigned coercion on us, it is an unsigned op
Expression* expr = process(ast[2][2]);
bool isSigned = !isParentUnsignedCoercion(astStackHelper.getParent());
bool isF64 = expr->type == Type::f64;
UnaryOp op;
if (isSigned && isF64) {
op = UnaryOp::TruncSFloat64ToInt32;
} else if (isSigned && !isF64) {
op = UnaryOp::TruncSFloat32ToInt32;
} else if (!isSigned && isF64) {
op = UnaryOp::TruncUFloat64ToInt32;
} else { // !isSigned && !isF64
op = UnaryOp::TruncUFloat32ToInt32;
}
return makeTrappingUnary(builder.makeUnary(op, expr),
trappingFunctions);
}
// no bitwise unary not, so do xor with -1
auto ret = allocator.alloc<Binary>();
ret->op = XorInt32;
ret->left = process(ast[2]);
ret->right = builder.makeConst(Literal(int32_t(-1)));
ret->type = Type::i32;
return ret;
} else if (ast[1] == L_NOT) {
auto ret = allocator.alloc<Unary>();
ret->op = EqZInt32;
ret->value = process(ast[2]);
ret->type = Type::i32;
return ret;
}
abort_on("bad unary", ast);
} else if (what == IF) {
auto* condition = process(ast[1]);
auto* ifTrue = process(ast[2]);
return builder.makeIf(truncateToInt32(condition),
ifTrue,
!!ast[3] ? process(ast[3]) : nullptr);
} else if (what == CALL) {
if (ast[1]->isString()) {
IString name = ast[1]->getIString();
if (name == Math_imul) {
assert(ast[2]->size() == 2);
auto ret = allocator.alloc<Binary>();
ret->op = MulInt32;
ret->left = process(ast[2][0]);
ret->right = process(ast[2][1]);
ret->type = Type::i32;
return ret;
}
if (name == Math_clz32 || name == llvm_cttz_i32) {
assert(ast[2]->size() == 1);
auto ret = allocator.alloc<Unary>();
ret->op = name == Math_clz32 ? ClzInt32 : CtzInt32;
ret->value = process(ast[2][0]);
ret->type = Type::i32;
return ret;
}
if (name == Math_fround) {
assert(ast[2]->size() == 1);
Literal lit = checkLiteral(ast[2][0], false /* raw is float */);
if (lit.type == Type::f64) {
return builder.makeConst(Literal((float)lit.getf64()));
}
auto ret = allocator.alloc<Unary>();
ret->value = process(ast[2][0]);
if (ret->value->type == Type::f64) {
ret->op = DemoteFloat64;
} else if (ret->value->type == Type::i32) {
if (isUnsignedCoercion(ast[2][0])) {
ret->op = ConvertUInt32ToFloat32;
} else {
ret->op = ConvertSInt32ToFloat32;
}
} else if (ret->value->type == Type::f32) {
return ret->value;
} else if (ret->value->type == Type::none) { // call, etc.
ret->value->type = Type::f32;
return ret->value;
} else {
abort_on("confusing fround target", ast[2][0]);
}
ret->type = Type::f32;
return ret;
}
if (name == Math_abs) {
// overloaded on type: i32, f32 or f64
Expression* value = process(ast[2][0]);
if (value->type == Type::i32) {
// No wasm support, so use a temp local
ensureI32Temp();
auto set = allocator.alloc<LocalSet>();
set->index = function->getLocalIndex(I32_TEMP);
set->value = value;
set->makeSet();
set->finalize();
auto get = [&]() {
auto ret = allocator.alloc<LocalGet>();
ret->index = function->getLocalIndex(I32_TEMP);
ret->type = Type::i32;
return ret;
};
auto isNegative = allocator.alloc<Binary>();
isNegative->op = LtSInt32;
isNegative->left = get();
isNegative->right = builder.makeConst(Literal(0));
isNegative->finalize();
auto block = allocator.alloc<Block>();
block->list.push_back(set);
auto flip = allocator.alloc<Binary>();
flip->op = SubInt32;
flip->left = builder.makeConst(Literal(0));
flip->right = get();
flip->type = Type::i32;
auto select = allocator.alloc<Select>();
select->ifTrue = flip;
select->ifFalse = get();
select->condition = isNegative;
select->type = Type::i32;
block->list.push_back(select);
block->finalize();
return block;
} else if (value->type == Type::f32 || value->type == Type::f64) {
auto ret = allocator.alloc<Unary>();
ret->op = value->type == Type::f32 ? AbsFloat32 : AbsFloat64;
ret->value = value;
ret->type = value->type;
return ret;
} else {
WASM_UNREACHABLE("unexpected type");
}
}
if (name == Math_floor || name == Math_sqrt || name == Math_ceil) {
// overloaded on type: f32 or f64
Expression* value = process(ast[2][0]);
auto ret = allocator.alloc<Unary>();
ret->value = value;
if (value->type == Type::f32) {
ret->op = name == Math_floor
? FloorFloat32
: name == Math_ceil ? CeilFloat32 : SqrtFloat32;
ret->type = value->type;
} else if (value->type == Type::f64) {
ret->op = name == Math_floor
? FloorFloat64
: name == Math_ceil ? CeilFloat64 : SqrtFloat64;
ret->type = value->type;
} else {
Fatal()
<< "floor/sqrt/ceil only work on float/double in asm.js and wasm";
}
return ret;
}
if (name == Math_max || name == Math_min) {
// overloaded on type: f32 or f64
assert(ast[2]->size() == 2);
auto ret = allocator.alloc<Binary>();
ret->left = process(ast[2][0]);
ret->right = process(ast[2][1]);
if (ret->left->type == Type::f32) {
ret->op = name == Math_max ? MaxFloat32 : MinFloat32;
} else if (ret->left->type == Type::f64) {
ret->op = name == Math_max ? MaxFloat64 : MinFloat64;
} else {
Fatal() << "min/max only work on float/double in asm.js and wasm";
}
ret->type = ret->left->type;
return ret;
}
if (name == Atomics_load || name == Atomics_store ||
name == Atomics_exchange || name == Atomics_compareExchange ||
name == Atomics_add || name == Atomics_sub || name == Atomics_and ||
name == Atomics_or || name == Atomics_xor) {
// atomic operation
Ref target = ast[2][0];
assert(target->isString());
IString heap = target->getIString();
assert(views.find(heap) != views.end());
View& view = views[heap];
wasm.memory.shared = true;
if (name == Atomics_load) {
Expression* ret =
builder.makeAtomicLoad(view.bytes,
0,
processUnshifted(ast[2][1], view.bytes),
asmToWasmType(view.type));
if (view.signed_) {
// atomic loads are unsigned; add a signing
ret = Bits::makeSignExt(ret, view.bytes, wasm);
}
return ret;
} else if (name == Atomics_store) {
// asm.js stores return the value, wasm does not
auto type = asmToWasmType(view.type);
auto temp = Builder::addVar(function, type);
return builder.makeSequence(
builder.makeAtomicStore(
view.bytes,
0,
processUnshifted(ast[2][1], view.bytes),
builder.makeLocalTee(temp, process(ast[2][2]), type),
type),
builder.makeLocalGet(temp, type));
} else if (name == Atomics_exchange) {
return builder.makeAtomicRMW(
AtomicRMWOp::Xchg,
view.bytes,
0,
processUnshifted(ast[2][1], view.bytes),
process(ast[2][2]),
asmToWasmType(view.type));
} else if (name == Atomics_compareExchange) {
// cmpxchg is odd in fastcomp output - we must ignore the shift, a
// cmpxchg of a i8 will look like compareExchange(HEAP8, ptr >> 2)
return builder.makeAtomicCmpxchg(
view.bytes,
0,
processIgnoringShift(ast[2][1], view.bytes),
process(ast[2][2]),
process(ast[2][3]),
asmToWasmType(view.type));
} else if (name == Atomics_add) {
return builder.makeAtomicRMW(
AtomicRMWOp::Add,
view.bytes,
0,
processUnshifted(ast[2][1], view.bytes),
process(ast[2][2]),
asmToWasmType(view.type));
} else if (name == Atomics_sub) {
return builder.makeAtomicRMW(
AtomicRMWOp::Sub,
view.bytes,
0,
processUnshifted(ast[2][1], view.bytes),
process(ast[2][2]),
asmToWasmType(view.type));
} else if (name == Atomics_and) {
return builder.makeAtomicRMW(
AtomicRMWOp::And,
view.bytes,
0,
processUnshifted(ast[2][1], view.bytes),
process(ast[2][2]),
asmToWasmType(view.type));
} else if (name == Atomics_or) {
return builder.makeAtomicRMW(
AtomicRMWOp::Or,
view.bytes,
0,
processUnshifted(ast[2][1], view.bytes),
process(ast[2][2]),
asmToWasmType(view.type));
} else if (name == Atomics_xor) {
return builder.makeAtomicRMW(
AtomicRMWOp::Xor,
view.bytes,
0,
processUnshifted(ast[2][1], view.bytes),
process(ast[2][2]),
asmToWasmType(view.type));
}
WASM_UNREACHABLE("unexpected atomic op");
}
bool tableCall = false;
if (wasmOnly) {
auto num = ast[2]->size();
switch (name.str[0]) {
case 'l': {
auto align = num == 2 ? ast[2][1]->getInteger() : 0;
if (name == LOAD1) {
return builder.makeLoad(
1, true, 0, 1, process(ast[2][0]), Type::i32);
}
if (name == LOAD2) {
return builder.makeLoad(
2, true, 0, indexOr(align, 2), process(ast[2][0]), Type::i32);
}
if (name == LOAD4) {
return builder.makeLoad(
4, true, 0, indexOr(align, 4), process(ast[2][0]), Type::i32);
}
if (name == LOAD8) {
return builder.makeLoad(
8, true, 0, indexOr(align, 8), process(ast[2][0]), Type::i64);
}
if (name == LOADF) {
return builder.makeLoad(
4, true, 0, indexOr(align, 4), process(ast[2][0]), Type::f32);
}
if (name == LOADD) {
return builder.makeLoad(
8, true, 0, indexOr(align, 8), process(ast[2][0]), Type::f64);
}
break;
}
case 's': {
auto align = num == 3 ? ast[2][2]->getInteger() : 0;
if (name == STORE1) {
return builder.makeStore(
1, 0, 1, process(ast[2][0]), process(ast[2][1]), Type::i32);
}
if (name == STORE2) {
return builder.makeStore(2,
0,
indexOr(align, 2),
process(ast[2][0]),
process(ast[2][1]),
Type::i32);
}
if (name == STORE4) {
return builder.makeStore(4,
0,
indexOr(align, 4),
process(ast[2][0]),
process(ast[2][1]),
Type::i32);
}
if (name == STORE8) {
return builder.makeStore(8,
0,
indexOr(align, 8),
process(ast[2][0]),
process(ast[2][1]),
Type::i64);
}
if (name == STOREF) {
auto* value = process(ast[2][1]);
if (value->type == Type::f64) {
// asm.js allows storing a double to HEAPF32, we must cast
// here
value = builder.makeUnary(DemoteFloat64, value);
}
return builder.makeStore(4,
0,
indexOr(align, 4),
process(ast[2][0]),
value,
Type::f32);
}
if (name == STORED) {
return builder.makeStore(8,
0,
indexOr(align, 8),
process(ast[2][0]),
process(ast[2][1]),
Type::f64);
}
break;
}
case 'i': {
if (num == 1) {
auto* value = process(ast[2][0]);
if (name == I64) {
// no-op "coercion" / "cast", although we also tolerate i64(0)
// for constants that fit in i32
if (value->type == Type::i32) {
return builder.makeConst(
Literal(int64_t(value->cast<Const>()->value.geti32())));
} else {
fixCallType(value, Type::i64);
return value;
}
}
if (name == I32_CTTZ) {
return builder.makeUnary(UnaryOp::CtzInt32, value);
}
if (name == I32_CTPOP) {
return builder.makeUnary(UnaryOp::PopcntInt32, value);
}
if (name == I32_BC2F) {
return builder.makeUnary(UnaryOp::ReinterpretInt32, value);
}
if (name == I32_BC2I) {
return builder.makeUnary(UnaryOp::ReinterpretFloat32, value);
}
if (name == I64_TRUNC) {
return builder.makeUnary(UnaryOp::WrapInt64, value);
}
if (name == I64_SEXT) {
return builder.makeUnary(UnaryOp::ExtendSInt32, value);
}
if (name == I64_ZEXT) {
return builder.makeUnary(UnaryOp::ExtendUInt32, value);
}
if (name == I64_S2F) {
return builder.makeUnary(UnaryOp::ConvertSInt64ToFloat32,
value);
}
if (name == I64_S2D) {
return builder.makeUnary(UnaryOp::ConvertSInt64ToFloat64,
value);
}
if (name == I64_U2F) {
return builder.makeUnary(UnaryOp::ConvertUInt64ToFloat32,
value);
}
if (name == I64_U2D) {
return builder.makeUnary(UnaryOp::ConvertUInt64ToFloat64,
value);
}
if (name == I64_F2S) {
Unary* conv =
builder.makeUnary(UnaryOp::TruncSFloat32ToInt64, value);
return makeTrappingUnary(conv, trappingFunctions);
}
if (name == I64_D2S) {
Unary* conv =
builder.makeUnary(UnaryOp::TruncSFloat64ToInt64, value);
return makeTrappingUnary(conv, trappingFunctions);
}
if (name == I64_F2U) {
Unary* conv =
builder.makeUnary(UnaryOp::TruncUFloat32ToInt64, value);
return makeTrappingUnary(conv, trappingFunctions);
}
if (name == I64_D2U) {
Unary* conv =
builder.makeUnary(UnaryOp::TruncUFloat64ToInt64, value);
return makeTrappingUnary(conv, trappingFunctions);
}
if (name == I64_BC2D) {
return builder.makeUnary(UnaryOp::ReinterpretInt64, value);
}
if (name == I64_BC2I) {
return builder.makeUnary(UnaryOp::ReinterpretFloat64, value);
}
if (name == I64_CTTZ) {
return builder.makeUnary(UnaryOp::CtzInt64, value);
}
if (name == I64_CTLZ) {
return builder.makeUnary(UnaryOp::ClzInt64, value);
}
if (name == I64_CTPOP) {
return builder.makeUnary(UnaryOp::PopcntInt64, value);
}
if (name == I64_ATOMICS_LOAD) {
return builder.makeAtomicLoad(8, 0, value, Type::i64);
}
} else if (num == 2) { // 2 params,binary
if (name == I64_CONST) {
return builder.makeConst(getLiteral(ast));
}
auto* left = process(ast[2][0]);
auto* right = process(ast[2][1]);
// maths
if (name == I64_ADD) {
return builder.makeBinary(BinaryOp::AddInt64, left, right);
}
if (name == I64_SUB) {
return builder.makeBinary(BinaryOp::SubInt64, left, right);
}
if (name == I64_MUL) {
return builder.makeBinary(BinaryOp::MulInt64, left, right);
}
if (name == I64_UDIV) {
Binary* div =
builder.makeBinary(BinaryOp::DivUInt64, left, right);
return makeTrappingBinary(div, trappingFunctions);
}
if (name == I64_SDIV) {
Binary* div =
builder.makeBinary(BinaryOp::DivSInt64, left, right);
return makeTrappingBinary(div, trappingFunctions);
}
if (name == I64_UREM) {
Binary* rem =
builder.makeBinary(BinaryOp::RemUInt64, left, right);
return makeTrappingBinary(rem, trappingFunctions);
}
if (name == I64_SREM) {
Binary* rem =
builder.makeBinary(BinaryOp::RemSInt64, left, right);
return makeTrappingBinary(rem, trappingFunctions);
}
if (name == I64_AND) {
return builder.makeBinary(BinaryOp::AndInt64, left, right);
}
if (name == I64_OR) {
return builder.makeBinary(BinaryOp::OrInt64, left, right);
}
if (name == I64_XOR) {
return builder.makeBinary(BinaryOp::XorInt64, left, right);
}
if (name == I64_SHL) {
return builder.makeBinary(BinaryOp::ShlInt64, left, right);
}
if (name == I64_ASHR) {
return builder.makeBinary(BinaryOp::ShrSInt64, left, right);
}
if (name == I64_LSHR) {
return builder.makeBinary(BinaryOp::ShrUInt64, left, right);
}
// comps
if (name == I64_EQ) {
return builder.makeBinary(BinaryOp::EqInt64, left, right);
}
if (name == I64_NE) {
return builder.makeBinary(BinaryOp::NeInt64, left, right);
}
if (name == I64_ULE) {
return builder.makeBinary(BinaryOp::LeUInt64, left, right);
}
if (name == I64_SLE) {
return builder.makeBinary(BinaryOp::LeSInt64, left, right);
}
if (name == I64_UGE) {
return builder.makeBinary(BinaryOp::GeUInt64, left, right);
}
if (name == I64_SGE) {
return builder.makeBinary(BinaryOp::GeSInt64, left, right);
}
if (name == I64_ULT) {
return builder.makeBinary(BinaryOp::LtUInt64, left, right);
}
if (name == I64_SLT) {
return builder.makeBinary(BinaryOp::LtSInt64, left, right);
}
if (name == I64_UGT) {
return builder.makeBinary(BinaryOp::GtUInt64, left, right);
}
if (name == I64_SGT) {
return builder.makeBinary(BinaryOp::GtSInt64, left, right);
}
// atomics
if (name == I64_ATOMICS_STORE) {
wasm.memory.shared = true;
return builder.makeAtomicStore(8, 0, left, right, Type::i64);
}
if (name == I64_ATOMICS_ADD) {
wasm.memory.shared = true;
return builder.makeAtomicRMW(
AtomicRMWOp::Add, 8, 0, left, right, Type::i64);
}
if (name == I64_ATOMICS_SUB) {
wasm.memory.shared = true;
return builder.makeAtomicRMW(
AtomicRMWOp::Sub, 8, 0, left, right, Type::i64);
}
if (name == I64_ATOMICS_AND) {
wasm.memory.shared = true;
return builder.makeAtomicRMW(
AtomicRMWOp::And, 8, 0, left, right, Type::i64);
}
if (name == I64_ATOMICS_OR) {
wasm.memory.shared = true;
return builder.makeAtomicRMW(
AtomicRMWOp::Or, 8, 0, left, right, Type::i64);
}
if (name == I64_ATOMICS_XOR) {
wasm.memory.shared = true;
return builder.makeAtomicRMW(
AtomicRMWOp::Xor, 8, 0, left, right, Type::i64);
}
if (name == I64_ATOMICS_EXCHANGE) {
wasm.memory.shared = true;
return builder.makeAtomicRMW(
AtomicRMWOp::Xchg, 8, 0, left, right, Type::i64);
}
} else if (num == 3) {
if (name == I64_ATOMICS_COMPAREEXCHANGE) {
wasm.memory.shared = true;
return builder.makeAtomicCmpxchg(8,
0,
process(ast[2][0]),
process(ast[2][1]),
process(ast[2][2]),
Type::i64);
}
}
break;
}
case 'f': {
if (name == F32_COPYSIGN) {
return builder.makeBinary(BinaryOp::CopySignFloat32,
process(ast[2][0]),
process(ast[2][1]));
}
if (name == F64_COPYSIGN) {
return builder.makeBinary(BinaryOp::CopySignFloat64,
process(ast[2][0]),
process(ast[2][1]));
}
break;
}
}
}
// ftCall_* and mftCall_* represent function table calls, either from
// the outside, or from the inside of the module. when compiling to
// wasm, we can just convert those into table calls
if ((name.str[0] == 'f' && strncmp(name.str, FTCALL.str, 7) == 0) ||
(name.str[0] == 'm' && strncmp(name.str, MFTCALL.str, 8) == 0)) {
tableCall = true;
}
Expression* ret;
ExpressionList* operands;
bool callImport = false;
Index firstOperand = 0;
Ref args = ast[2];
if (tableCall) {
auto specific = allocator.alloc<CallIndirect>();
specific->target = process(args[0]);
firstOperand = 1;
operands = &specific->operands;
ret = specific;
} else {
// if we call an import, it definitely exists already; if it's a
// defined function then it might not have been seen yet
auto* target = wasm.getFunctionOrNull(name);
callImport = target && target->imported();
auto specific = allocator.alloc<Call>();
specific->target = name;
operands = &specific->operands;
ret = specific;
}
for (unsigned i = firstOperand; i < args->size(); i++) {
operands->push_back(process(args[i]));
}
if (tableCall) {
auto specific = ret->dynCast<CallIndirect>();
// note that we could also get the type from the suffix of the name,
// e.g., mftCall_vi
auto sig = getSignature(
astStackHelper.getParent(), specific->operands, &asmData);
specific->sig = sig;
specific->type = sig.results;
}
if (callImport) {
// apply the detected type from the parent
// note that this may not be complete, e.g. we may see f(); but f is
// an import which does return a value, and we use that elsewhere.
// finalizeCalls fixes that up. what we do here is wherever a value is
// used, we set the right value, which is enough to ensure that the
// wasm ast is valid for such uses. this is important as we run the
// optimizer on functions before we get to finalizeCalls (which we can
// only do once we've read all the functions, and we optimize in
// parallel starting earlier).
auto* call = ret->cast<Call>();
call->type = getResultTypeOfCallUsingParent(
astStackHelper.getParent(), &asmData);
noteImportedFunctionCall(ast, call->type, call);
}
return ret;
}
// function pointers
auto ret = allocator.alloc<CallIndirect>();
Ref target = ast[1];
assert(target[0] == SUB && target[1]->isString() &&
target[2][0] == BINARY && target[2][1] == AND &&
target[2][3]->isNumber()); // FUNCTION_TABLE[(expr) & mask]
// TODO: as an optimization, we could look through the mask
ret->target = process(target[2]);
Ref args = ast[2];
for (unsigned i = 0; i < args->size(); i++) {
ret->operands.push_back(process(args[i]));
}
auto sig =
getSignature(astStackHelper.getParent(), ret->operands, &asmData);
ret->sig = sig;
ret->type = sig.results;
// we don't know the table offset yet. emit target = target +
// callImport(tableName), which we fix up later when we know how asm
// function tables are layed out inside the wasm table.
ret->target = builder.makeBinary(
BinaryOp::AddInt32,
ret->target,
builder.makeCall(target[1]->getIString(), {}, Type::i32));
return ret;
} else if (what == RETURN) {
Type type = !!ast[1] ? detectWasmType(ast[1], &asmData) : Type::none;
if (seenReturn) {
assert(function->sig.results == type);
} else {
function->sig.results = type;
}
// wasm has no return, so we just break on the topmost block
auto ret = allocator.alloc<Return>();
ret->value = !!ast[1] ? process(ast[1]) : nullptr;
return ret;
} else if (what == BLOCK) {
Name name;
if (parentLabel.is()) {
name = nameMapper.pushLabelName(getBreakLabelName(parentLabel));
parentLabel = IString();
breakStack.push_back(name);
}
auto ret = processStatements(ast[1], 0);
if (name.is()) {
breakStack.pop_back();
nameMapper.popLabelName(name);
Block* block = ret->dynCast<Block>();
if (block && block->name.isNull()) {
block->name = name;
} else {
block = allocator.alloc<Block>();
block->name = name;
block->list.push_back(ret);
block->finalize();
ret = block;
}
}
return ret;
} else if (what == BREAK) {
auto ret = allocator.alloc<Break>();
assert(breakStack.size() > 0);
ret->name =
!!ast[1]
? nameMapper.sourceToUnique(getBreakLabelName(ast[1]->getIString()))
: breakStack.back();
return ret;
} else if (what == CONTINUE) {
auto ret = allocator.alloc<Break>();
assert(continueStack.size() > 0);
ret->name = !!ast[1] ? nameMapper.sourceToUnique(
getContinueLabelName(ast[1]->getIString()))
: continueStack.back();
return ret;
} else if (what == WHILE) {
bool forever = ast[1]->isNumber() && ast[1]->getInteger() == 1;
auto ret = allocator.alloc<Loop>();
IString out, in;
if (!parentLabel.isNull()) {
out = getBreakLabelName(parentLabel);
in = getContinueLabelName(parentLabel);
parentLabel = IString();
} else {
out = "while-out";
in = "while-in";
}
out = nameMapper.pushLabelName(out);
in = nameMapper.pushLabelName(in);
ret->name = in;
breakStack.push_back(out);
continueStack.push_back(in);
if (forever) {
ret->body = process(ast[2]);
} else {
Break* breakOut = allocator.alloc<Break>();
breakOut->name = out;
If* condition = allocator.alloc<If>();
condition->condition = builder.makeUnary(EqZInt32, process(ast[1]));
condition->ifTrue = breakOut;
condition->finalize();
auto body = allocator.alloc<Block>();
body->list.push_back(condition);
body->list.push_back(process(ast[2]));
body->finalize();
ret->body = body;
}
// loops do not automatically loop, add a branch back
Block* block = builder.blockifyWithName(ret->body, out);
auto continuer = allocator.alloc<Break>();
continuer->name = ret->name;
block->list.push_back(continuer);
block->finalize();
ret->body = block;
ret->finalize();
continueStack.pop_back();
breakStack.pop_back();
nameMapper.popLabelName(in);
nameMapper.popLabelName(out);
return ret;
} else if (what == DO) {
if (ast[1]->isNumber() && ast[1]->getNumber() == 0) {
// one-time loop, unless there is a continue
IString stop;
if (!parentLabel.isNull()) {
stop = getBreakLabelName(parentLabel);
parentLabel = IString();
} else {
stop = "do-once";
}
stop = nameMapper.pushLabelName(stop);
Name more = nameMapper.pushLabelName("unlikely-continue");
breakStack.push_back(stop);
continueStack.push_back(more);
auto child = process(ast[2]);
continueStack.pop_back();
breakStack.pop_back();
nameMapper.popLabelName(more);
nameMapper.popLabelName(stop);
// if we never continued, we don't need a loop
BranchUtils::BranchSeeker seeker(more);
seeker.walk(child);
if (seeker.found == 0) {
auto block = allocator.alloc<Block>();
block->list.push_back(child);
if (child->type.isConcrete()) {
// ensure a nop at the end, so the block has guaranteed none type
// and no values fall through
block->list.push_back(builder.makeNop());
}
block->name = stop;
block->finalize();
return block;
} else {
auto loop = allocator.alloc<Loop>();
loop->body = child;
loop->name = more;
loop->finalize();
return builder.blockifyWithName(loop, stop);
}
}
// general do-while loop
auto loop = allocator.alloc<Loop>();
IString out, in;
if (!parentLabel.isNull()) {
out = getBreakLabelName(parentLabel);
in = getContinueLabelName(parentLabel);
parentLabel = IString();
} else {
out = "do-out";
in = "do-in";
}
out = nameMapper.pushLabelName(out);
in = nameMapper.pushLabelName(in);
loop->name = in;
breakStack.push_back(out);
continueStack.push_back(in);
loop->body = process(ast[2]);
continueStack.pop_back();
breakStack.pop_back();
nameMapper.popLabelName(in);
nameMapper.popLabelName(out);
Break* continuer = allocator.alloc<Break>();
continuer->name = in;
continuer->condition = process(ast[1]);
continuer->finalize();
Block* block = builder.blockifyWithName(loop->body, out, continuer);
loop->body = block;
loop->finalize();
return loop;
} else if (what == FOR) {
Ref finit = ast[1], fcond = ast[2], finc = ast[3], fbody = ast[4];
auto ret = allocator.alloc<Loop>();
IString out, in;
if (!parentLabel.isNull()) {
out = getBreakLabelName(parentLabel);
in = getContinueLabelName(parentLabel);
parentLabel = IString();
} else {
out = "for-out";
in = "for-in";
}
out = nameMapper.pushLabelName(out);
in = nameMapper.pushLabelName(in);
ret->name = in;
breakStack.push_back(out);
continueStack.push_back(in);
Break* breakOut = allocator.alloc<Break>();
breakOut->name = out;
If* condition = allocator.alloc<If>();
condition->condition = builder.makeUnary(EqZInt32, process(fcond));
condition->ifTrue = breakOut;
condition->finalize();
auto body = allocator.alloc<Block>();
body->list.push_back(condition);
body->list.push_back(process(fbody));
body->list.push_back(process(finc));
body->finalize();
ret->body = body;
// loops do not automatically loop, add a branch back
auto continuer = allocator.alloc<Break>();
continuer->name = ret->name;
Block* block = builder.blockifyWithName(ret->body, out, continuer);
ret->body = block;
ret->finalize();
continueStack.pop_back();
breakStack.pop_back();
nameMapper.popLabelName(in);
nameMapper.popLabelName(out);
Block* outer = allocator.alloc<Block>();
// add an outer block for the init as well
outer->list.push_back(process(finit));
outer->list.push_back(ret);
outer->finalize();
return outer;
} else if (what == LABEL) {
assert(parentLabel.isNull());
parentLabel = ast[1]->getIString();
return process(ast[2]);
} else if (what == CONDITIONAL) {
auto ret = allocator.alloc<If>();
ret->condition = process(ast[1]);
ret->ifTrue = process(ast[2]);
ret->ifFalse = process(ast[3]);
ret->finalize();
return ret;
} else if (what == SEQ) {
// Some (x, y) patterns can be optimized, like bitcasts,
// (HEAP32[tempDoublePtr >> 2] = i,
// Math_fround(HEAPF32[tempDoublePtr >> 2])); // i32->f32
// (HEAP32[tempDoublePtr >> 2] = i,
// +HEAPF32[tempDoublePtr >> 2]); // i32->f32, no fround
// (HEAPF32[tempDoublePtr >> 2] = f,
// HEAP32[tempDoublePtr >> 2] | 0); // f32->i32
if (ast[1]->isAssign()) {
auto* assign = ast[1]->asAssign();
Ref target = assign->target();
if (target->isArray(SUB) && target[1]->isString() &&
target[2]->isArray(BINARY) && target[2][1] == RSHIFT &&
target[2][2]->isString() && target[2][2] == tempDoublePtr &&
target[2][3]->isNumber() && target[2][3]->getNumber() == 2) {
// (?[tempDoublePtr >> 2] = ?, ?) so far
auto heap = target[1]->getIString();
if (views.find(heap) != views.end()) {
AsmType writeType = views[heap].type;
AsmType readType = ASM_NONE;
Ref readValue;
if (ast[2]->isArray(BINARY) && ast[2][1] == OR &&
ast[2][3]->isNumber() && ast[2][3]->getNumber() == 0) {
readType = ASM_INT;
readValue = ast[2][2];
} else if (ast[2]->isArray(UNARY_PREFIX) && ast[2][1] == PLUS) {
readType = ASM_DOUBLE;
readValue = ast[2][2];
} else if (ast[2]->isArray(CALL) && ast[2][1]->isString() &&
ast[2][1] == Math_fround) {
readType = ASM_FLOAT;
readValue = ast[2][2][0];
}
if (readType != ASM_NONE) {
if (readValue->isArray(SUB) && readValue[1]->isString() &&
readValue[2]->isArray(BINARY) && readValue[2][1] == RSHIFT &&
readValue[2][2]->isString() &&
readValue[2][2] == tempDoublePtr &&
readValue[2][3]->isNumber() &&
readValue[2][3]->getNumber() == 2) {
// pattern looks right!
Ref writtenValue = assign->value();
if (writeType == ASM_INT &&
(readType == ASM_FLOAT || readType == ASM_DOUBLE)) {
auto conv = allocator.alloc<Unary>();
conv->op = ReinterpretInt32;
conv->value = process(writtenValue);
conv->type = Type::f32;
if (readType == ASM_DOUBLE) {
return ensureDouble(conv);
}
return conv;
} else if (writeType == ASM_FLOAT && readType == ASM_INT) {
auto conv = allocator.alloc<Unary>();
conv->op = ReinterpretFloat32;
conv->value = process(writtenValue);
if (conv->value->type == Type::f64) {
// this has an implicit f64->f32 in the write to memory
conv->value = builder.makeUnary(DemoteFloat64, conv->value);
}
conv->type = Type::i32;
return conv;
}
}
}
}
}
}
auto ret = allocator.alloc<Block>();
ret->list.push_back(process(ast[1]));
ret->list.push_back(process(ast[2]));
ret->finalize();
return ret;
} else if (what == SWITCH) {
IString name; // for breaking out of the entire switch
if (!parentLabel.isNull()) {
name = getBreakLabelName(parentLabel);
parentLabel = IString();
} else {
name = "switch";
}
name = nameMapper.pushLabelName(name);
breakStack.push_back(name);
auto br = allocator.alloc<Switch>();
br->condition = process(ast[1]);
Ref cases = ast[2];
bool seen = false;
int64_t min = 0; // the lowest index we see; we will offset to it
int64_t max = 0; // the highest, to check if the range is too big
for (unsigned i = 0; i < cases->size(); i++) {
Ref curr = cases[i];
Ref condition = curr[0];
if (!condition->isNull()) {
int64_t index = getLiteral(condition).getInteger();
if (!seen) {
seen = true;
min = index;
max = index;
} else {
if (index < min) {
min = index;
}
if (index > max) {
max = index;
}
}
}
}
// we can use a switch if it's not too big
auto range = double(max) - double(min); // test using doubles to avoid UB
bool canSwitch = 0 <= range && range < 10240;
auto top = allocator.alloc<Block>();
if (canSwitch) {
// we may need a break for the case where the condition doesn't match
// any of the cases. it should go to the default, if we have one, or
// outside if not
Break* breakWhenNotMatching = nullptr;
if (br->condition->type == Type::i32) {
Binary* offsetor = allocator.alloc<Binary>();
offsetor->op = BinaryOp::SubInt32;
offsetor->left = br->condition;
offsetor->right = builder.makeConst(Literal(int32_t(min)));
offsetor->type = Type::i32;
br->condition = offsetor;
} else {
assert(br->condition->type == Type::i64);
// 64-bit condition. after offsetting it must be in a reasonable
// range, but the offsetting itself must be 64-bit
Binary* offsetor = allocator.alloc<Binary>();
offsetor->op = BinaryOp::SubInt64;
offsetor->left = br->condition;
offsetor->right = builder.makeConst(Literal(int64_t(min)));
offsetor->type = Type::i64;
// the switch itself can be 32-bit, as the range is in a reasonable
// range. so after offsetting, we need to make sure there are no high
// bits, then we can just look at the lower 32 bits
auto temp = Builder::addVar(function, Type::i64);
auto* block = builder.makeBlock();
block->list.push_back(builder.makeLocalSet(temp, offsetor));
// if high bits, we can break to the default (we'll fill in the name
// later)
breakWhenNotMatching = builder.makeBreak(
Name(),
nullptr,
builder.makeUnary(
UnaryOp::WrapInt64,
builder.makeBinary(BinaryOp::ShrUInt64,
builder.makeLocalGet(temp, Type::i64),
builder.makeConst(Literal(int64_t(32))))));
block->list.push_back(breakWhenNotMatching);
block->list.push_back(builder.makeLocalGet(temp, Type::i64));
block->finalize();
br->condition = builder.makeUnary(UnaryOp::WrapInt64, block);
}
top->list.push_back(br);
for (unsigned i = 0; i < cases->size(); i++) {
Ref curr = cases[i];
Ref condition = curr[0];
Ref body = curr[1];
auto case_ = processStatements(body, 0);
Name name;
if (condition->isNull()) {
name = br->default_ = nameMapper.pushLabelName("switch-default");
} else {
auto index = getLiteral(condition).getInteger();
assert(index >= min);
index -= min;
assert(index >= 0);
uint64_t index_s = index;
name = nameMapper.pushLabelName("switch-case");
if (br->targets.size() <= index_s) {
br->targets.resize(index_s + 1);
}
br->targets[index_s] = name;
}
auto next = allocator.alloc<Block>();
top->name = name;
next->list.push_back(top);
next->list.push_back(case_);
next->finalize();
top = next;
nameMapper.popLabelName(name);
}
// the outermost block can be branched to to exit the whole switch
top->name = name;
// ensure a default
if (br->default_.isNull()) {
br->default_ = top->name;
}
if (breakWhenNotMatching) {
breakWhenNotMatching->name = br->default_;
}
for (size_t i = 0; i < br->targets.size(); i++) {
if (br->targets[i].isNull()) {
br->targets[i] = br->default_;
}
}
} else {
// we can't switch, make an if-chain instead of br_table
auto var = Builder::addVar(function, br->condition->type);
top->list.push_back(builder.makeLocalSet(var, br->condition));
auto* brHolder = top;
If* chain = nullptr;
If* first = nullptr;
for (unsigned i = 0; i < cases->size(); i++) {
Ref curr = cases[i];
Ref condition = curr[0];
Ref body = curr[1];
auto case_ = processStatements(body, 0);
Name name;
if (condition->isNull()) {
name = br->default_ = nameMapper.pushLabelName("switch-default");
} else {
name = nameMapper.pushLabelName("switch-case");
auto* iff = builder.makeIf(
builder.makeBinary(br->condition->type == Type::i32 ? EqInt32
: EqInt64,
builder.makeLocalGet(var, br->condition->type),
builder.makeConst(getLiteral(condition))),
builder.makeBreak(name),
chain);
chain = iff;
if (!first) {
first = iff;
}
}
auto next = allocator.alloc<Block>();
top->name = name;
next->list.push_back(top);
next->list.push_back(case_);
top = next;
nameMapper.popLabelName(name);
}
// the outermost block can be branched to to exit the whole switch
top->name = name;
// ensure a default
if (br->default_.isNull()) {
br->default_ = top->name;
}
first->ifFalse = builder.makeBreak(br->default_);
brHolder->list.push_back(chain);
}
breakStack.pop_back();
nameMapper.popLabelName(name);
return top;
}
abort_on("confusing expression", ast);
return (Expression*)nullptr; // avoid warning
};
// given HEAP32[addr >> 2], we need an absolute address, and would like to
// remove that shift. if there is a shift, we can just look through it, etc.
processUnshifted = [&](Ref ptr, unsigned bytes) {
auto shifts = bytesToShift(bytes);
// HEAP?[addr >> ?], or HEAP8[x | 0]
if ((ptr->isArray(BINARY) && ptr[1] == RSHIFT && ptr[3]->isNumber() &&
ptr[3]->getInteger() == shifts) ||
(bytes == 1 && ptr->isArray(BINARY) && ptr[1] == OR &&
ptr[3]->isNumber() && ptr[3]->getInteger() == 0)) {
return process(ptr[2]); // look through it
} else if (ptr->isNumber()) {
// constant, apply a shift (e.g. HEAP32[1] is address 4)
unsigned addr = ptr->getInteger();
unsigned shifted = addr << shifts;
return (Expression*)builder.makeConst(Literal(int32_t(shifted)));
}
abort_on("bad processUnshifted", ptr);
return (Expression*)nullptr; // avoid warning
};
processIgnoringShift = [&](Ref ptr, unsigned bytes) {
// If there is a shift here, no matter the size look through it.
if ((ptr->isArray(BINARY) && ptr[1] == RSHIFT && ptr[3]->isNumber()) ||
(bytes == 1 && ptr->isArray(BINARY) && ptr[1] == OR &&
ptr[3]->isNumber() && ptr[3]->getInteger() == 0)) {
return process(ptr[2]);
}
// Otherwise do the same as processUnshifted.
return processUnshifted(ptr, bytes);
};
processStatements = [&](Ref ast, unsigned from) -> Expression* {
unsigned size = ast->size() - from;
if (size == 0) {
return allocator.alloc<Nop>();
}
if (size == 1) {
return process(ast[from]);
}
auto block = allocator.alloc<Block>();
for (unsigned i = from; i < ast->size(); i++) {
block->list.push_back(process(ast[i]));
}
block->finalize();
return block;
};
// body
function->body = processStatements(body, start);
// cleanups/checks
assert(breakStack.size() == 0 && continueStack.size() == 0);
assert(parentLabel.isNull());
return function;
}
} // namespace wasm
#endif // wasm_asm2wasm_h