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CPU/Recompiler: Optimize bgez zero, addr to unconditional

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This commit is contained in:
Connor McLaughlin 2021-06-13 18:06:28 +10:00
parent 0ba405ef2d
commit e8ac1fca80
1 changed files with 6 additions and 2 deletions
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8
src/core/cpu_recompiler_code_generator.cpp
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@ -2311,11 +2311,15 @@ bool CodeGenerator::Compile_Branch(const CodeBlockInstruction& cbi)
const u8 rt = static_cast<u8>(cbi.instruction.i.rt.GetValue());
const bool bgez = ConvertToBoolUnchecked(rt & u8(1));
const Condition condition = bgez ? Condition::PositiveOrZero : Condition::Negative;
const Condition condition = (bgez && cbi.instruction.r.rs == Reg::zero) ?
Condition::Always :
(bgez ? Condition::PositiveOrZero : Condition::Negative);
const bool link = (rt & u8(0x1E)) == u8(0x10);
// Read has to happen before the link as the compare can use ra.
Value lhs = m_register_cache.ReadGuestRegisterToScratch(cbi.instruction.i.rs);
Value lhs;
if (condition != Condition::Always)
lhs = m_register_cache.ReadGuestRegisterToScratch(cbi.instruction.i.rs);
// The return address is always written if link is set, regardless of whether the branch is taken.
if (link)