JIT/x86: Fix reported kill regs for varargs prologs #113793
Merged
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PR #100823 stopped the hidden stub arg on x86 from being
do-not-enregister
. There's a code specifically for varargs prologs that depended on that behavior and trashes the EAX register (the same register used for the hidden arg):runtime/src/coreclr/jit/codegencommon.cpp
Lines 5925 to 5931 in 1f76c1f
Luckily, the bug doesn't manifest because we currenly never pair varargs with
JIT_FLAG_USE_PINVOKE_HELPERS
. This meant that we always emitted call toCORINFO_HELP_INIT_PINVOKE_FRAME
helper call which also killed the EAX register.