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https://github.com/FEX-Emu/FEX.git
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Ryan Houdek
e817f5d98c
A bit meta since it needs to JIT some minor code but easy enough. Ensures something like #1517 won't happen again.
51 lines
940 B
NASM
51 lines
940 B
NASM
%ifdef CONFIG
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{
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"RegData": {
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"RAX": "0x41424344"
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},
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"Mode": "32BIT"
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}
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%endif
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; Tests for 32-bit signed displacement wrapping
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; Testing for overflow specifically
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; Will crash or hit the code we emit to memory
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; We map ten pages to 0xe000'0000
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; Generate a call 0x11000 over there
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; 0x0f'83'fa'0f'01'20 : jnb 0x11000
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; 0xf4: hlt - Just in case
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mov ebx, 0xe0000000
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mov ax, 0x830f
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mov word [ebx], ax
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mov eax, 0x20010ffa
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mov dword [ebx + 2], eax
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mov al, 0xf4
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mov byte [ebx + 6], al
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; Do a jump dance to stop multiblock from trying to optimize
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; Otherwise it will JIT code from 0xe000'0000 before written
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lea ebx, [rel next]
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jmp ebx
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next:
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; Move temp to eax to overwrite
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mov eax, 0
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; Clear the lower flags so the branch gets taken
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sahf
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; This is dependent on where it is in the code!
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jnb -0x20000000
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; Definitely wrong if we hit here
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mov eax, -1
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hlt
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; This is where the JIT code will land
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align 0x1000
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mov eax, 0x41424344
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hlt
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