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Merge pull request #3256 from Sonicadvance1/unittest_for_3254
unittests/ASM: Adds unittest for implicit flag clobber for #3254
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%ifdef CONFIG | ||
{ | ||
"RegData": { | ||
"RAX": "0", | ||
"XMM0": ["0", "0"] | ||
} | ||
} | ||
%endif | ||
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; FEX has a bug with NZCV host flag usage that IR operations that implicitly clobber flags might not save emulated eflags correctly in all instances. | ||
; This tests one particular instance of `ImplicitFlagClobber`. | ||
movaps xmm0, [rel .data] | ||
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; Calculate ZF up-front | ||
mov eax, 1 | ||
add eax, eax | ||
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; This jump is necessary to break visibility. | ||
jmp .begin | ||
.begin: | ||
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; minss turns in to VFMinScalarInsert which implicitly clobbers Arm64 flags. | ||
; Potentially any instruction that uses an IR operation that uses `ImplicitFlagClobber` would break. | ||
minss xmm0, xmm0 | ||
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; Ensure the flags calculated by the `add eax, eax` are consumed. | ||
; ZF should be unset from `add 1, 1`. | ||
; If minss clobbers Arm64 host flags then the `fcmp` that Arm64 uses will overwrite nzcv, thus setting the ZF flag. | ||
; This is since `fcmp #0, #0` will set nzcv to `0110`. | ||
jnz .next | ||
mov eax, 1 | ||
hlt | ||
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.next: | ||
mov eax, 0 | ||
hlt | ||
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align 16 | ||
.data: | ||
dd 0, 0, 0, 0 |