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--- src/3rdparty/chromium/v8/src/wasm/jump-table-assembler.cc.orig 2023-07-16 15:47:57 UTC
+++ src/3rdparty/chromium/v8/src/wasm/jump-table-assembler.cc
@@ -52,15 +52,21 @@ void JumpTableAssembler::InitializeJumpsToLazyCompileT
#if V8_TARGET_ARCH_X64
void JumpTableAssembler::EmitLazyCompileJumpSlot(uint32_t func_index,
Address lazy_compile_target) {
+ intptr_t displacement =
+ static_cast<intptr_t>(reinterpret_cast<uint8_t*>(lazy_compile_target) -
+ (pc_ + 9) - kNearJmpInstrSize);
+ if (!is_int32(displacement)) return;
+ CodeEntry(); // 4 bytes
// Use a push, because mov to an extended register takes 6 bytes.
- pushq_imm32(func_index); // 5 bytes
- EmitJumpSlot(lazy_compile_target); // 5 bytes
+ pushq_imm32(func_index); // 5 bytes
+ near_jmp(displacement, RelocInfo::NO_INFO); // 5 bytes
}
bool JumpTableAssembler::EmitJumpSlot(Address target) {
intptr_t displacement = static_cast<intptr_t>(
- reinterpret_cast<uint8_t*>(target) - pc_ - kNearJmpInstrSize);
+ reinterpret_cast<uint8_t*>(target) - (pc_ + 4) - kNearJmpInstrSize);
if (!is_int32(displacement)) return false;
+ CodeEntry(); // 4 bytes
near_jmp(displacement, RelocInfo::NO_INFO); // 5 bytes
return true;
}
@@ -68,11 +74,12 @@ bool JumpTableAssembler::EmitJumpSlot(Address target)
void JumpTableAssembler::EmitFarJumpSlot(Address target) {
Label data;
int start_offset = pc_offset();
+ CodeEntry(); // 4 bytes
jmp(Operand(&data)); // 6 bytes
- Nop(2); // 2 bytes
+ Nop(6); // 6 bytes
// The data must be properly aligned, so it can be patched atomically (see
// {PatchFarJumpSlot}).
- DCHECK_EQ(start_offset + kSystemPointerSize, pc_offset());
+ DCHECK_EQ(start_offset + kFarJumpTableSlotOffset, pc_offset());
USE(start_offset);
bind(&data);
dq(target); // 8 bytes
@@ -83,7 +90,7 @@ void JumpTableAssembler::PatchFarJumpSlot(Address slot
// The slot needs to be pointer-size aligned so we can atomically update it.
DCHECK(IsAligned(slot, kSystemPointerSize));
// Offset of the target is at 8 bytes, see {EmitFarJumpSlot}.
- reinterpret_cast<std::atomic<Address>*>(slot + kSystemPointerSize)
+ reinterpret_cast<std::atomic<Address>*>(slot + kFarJumpTableSlotOffset)
->store(target, std::memory_order_relaxed);
// The update is atomic because the address is properly aligned.
// Because of cache coherence, the data update will eventually be seen by all
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