blob: 44c871ea41b205a01d9f11741292ce5fc2ca88b8 [file] [log] [blame]
/* **********************************************************
* Copyright (c) 2014-2020 Google, Inc. All rights reserved.
* **********************************************************/
/*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* * Neither the name of Google, Inc. nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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* DAMAGE.
*/
/*
* cross-platform assembly and trampoline code
*/
#include "../arch/asm_defines.asm"
START_FILE
DECL_EXTERN(d_r_internal_error)
/* For debugging: report an error if the function called by call_switch_stack()
* unexpectedly returns. Also used elsewhere.
* i#4304: When calling this function do not use short branch instructions,
* e.g., conditional branch instructions on aarch64. They don't have enough
* bits of offset to reach this. Instead, use unconditional branch or
* call instructions (e.g., b, bl on aarch64) that have a sufficient number
* of bits. On x86, and other architectures where a call instruction requires
* the stack, only use branch instructions: This can get called when there
* is insufficient stack.
*/
DECLARE_FUNC(unexpected_return)
GLOBAL_LABEL(unexpected_return:)
CALLC3(GLOBAL_REF(d_r_internal_error), HEX(0), HEX(0), HEX(0))
/* d_r_internal_error normally never returns */
/* Infinite loop is intentional. Can we do better in release build?
* XXX: why not a debug instr?
*/
JUMP GLOBAL_REF(unexpected_return)
END_FUNC(unexpected_return)
END_FILE