Revert "[Salvage] Change salvage debug info implementation to use DW_OP_LLVM_convert where needed"

This reverts r360772 due to build issues.
Reverted commit: 17dd4d7403770bd683675e45f5517e0cdb8f9b2b.

llvm-svn: 360773
diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 04e6cbb..2a4e905 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -1690,27 +1690,8 @@
     // No-op casts and zexts are irrelevant for debug info.
     if (CI->isNoopCast(DL) || isa<ZExtInst>(&I))
       return SrcDIExpr;
-
-    Type *Type = CI->getType();
-    // Casts other than Trunc or SExt to scalar types cannot be salvaged.
-    if (Type->isVectorTy() || (!isa<TruncInst>(&I) && !isa<SExtInst>(&I)))
-      return nullptr;
-
-    Value *FromValue = CI->getOperand(0);
-    unsigned FromTypeBitSize = FromValue->getType()->getScalarSizeInBits();
-
-    unsigned ToTypeBitSize = Type->getScalarSizeInBits();
-
-    // The result of the cast will be sign extended iff the instruction is a
-    // SExt; signedness is otherwise irrelevant on the expression stack.
-    unsigned Encoding =
-        isa<SExtInst>(&I) ? dwarf::DW_ATE_signed : dwarf::DW_ATE_unsigned;
-
-    return applyOps({dwarf::DW_OP_LLVM_convert, FromTypeBitSize, Encoding,
-                     dwarf::DW_OP_LLVM_convert, ToTypeBitSize, Encoding});
-  }
-
-  if (auto *GEP = dyn_cast<GetElementPtrInst>(&I)) {
+    return nullptr;
+  } else if (auto *GEP = dyn_cast<GetElementPtrInst>(&I)) {
     unsigned BitWidth =
         M.getDataLayout().getIndexSizeInBits(GEP->getPointerAddressSpace());
     // Rewrite a constant GEP into a DIExpression.
diff --git a/llvm/test/DebugInfo/salvage-cast-debug-info.ll b/llvm/test/DebugInfo/salvage-cast-debug-info.ll
deleted file mode 100755
index 1c8196a..0000000
--- a/llvm/test/DebugInfo/salvage-cast-debug-info.ll
+++ /dev/null
@@ -1,25 +0,0 @@
-; RUN: opt %s -debugify -early-cse -S | FileCheck %s
-define i32 @foo(i64 %nose, i32 %more) {
-; CHECK-LABEL: @foo(
-; CHECK: call void @llvm.dbg.value(metadata i64 %nose, metadata [[V1:![0-9]+]], metadata !DIExpression(DW_OP_LLVM_convert, 64, DW_ATE_unsigned, DW_OP_LLVM_convert, 32, DW_ATE_unsigned
-; CHECK: call void @llvm.dbg.value(metadata i64 %nose.shift, metadata [[V2:![0-9]+]]
-; CHECK: call void @llvm.dbg.value(metadata i64 %nose.shift, metadata [[V3:![0-9]+]], metadata !DIExpression(DW_OP_LLVM_convert, 64, DW_ATE_unsigned, DW_OP_LLVM_convert, 32, DW_ATE_unsigned
-
-entry:
-  %nose.trunc = trunc i64 %nose to i32
-  %nose.shift = lshr i64 %nose, 32
-  %nose.trunc.2 = trunc i64 %nose.shift to i32
-  %add = add nsw i32 %more, 1
-  ret i32 %add
-}
-
-!llvm.module.flags = !{!0, !1}
-!llvm.ident = !{!2}
-
-!0 = !{i32 1, !"wchar_size", i32 2}
-!1 = !{i32 7, !"PIC Level", i32 2}
-!2 = !{!"clang version 9.0.0 "}
-
-; CHECK: [[V1]] = !DILocalVariable(
-; CHECK: [[V2]] = !DILocalVariable(
-; CHECK: [[V3]] = !DILocalVariable(
diff --git a/llvm/test/Transforms/InstCombine/cast-mul-select.ll b/llvm/test/Transforms/InstCombine/cast-mul-select.ll
index f82d2fd..c501fd8 100644
--- a/llvm/test/Transforms/InstCombine/cast-mul-select.ll
+++ b/llvm/test/Transforms/InstCombine/cast-mul-select.ll
@@ -13,8 +13,6 @@
 ; we preserve the debug information in the resulting
 ; instruction.
 ; DBGINFO-LABEL: @mul(
-; DBGINFO-NEXT:    call void @llvm.dbg.value(metadata i32 %x
-; DBGINFO-NEXT:    call void @llvm.dbg.value(metadata i32 %y
 ; DBGINFO-NEXT:    [[C:%.*]] = mul i32 {{.*}}
 ; DBGINFO-NEXT:    [[D:%.*]] = and i32 {{.*}}
 ; DBGINFO-NEXT:    call void @llvm.dbg.value(metadata i32 [[C]]