6f65b65f7d
I've wrestled for a long time with how to support integer division with its hard-coded registers. The answer's always been staring me in the face: just turn it into a function! We already expect function outputs to go to hard-coded registers.
18 lines
429 B
Plaintext
18 lines
429 B
Plaintext
== code
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integer-divide: # a: int, b: int -> quotient/eax: int, remainder/edx: int
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# . prologue
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55/push-ebp
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89/<- %ebp 4/r32/esp
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# eax = a
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8b/-> *(ebp+8) 0/r32/eax
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# edx = all 0s or all 1s
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99/sign-extend-eax-into-edx
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# quotient, remainder = divide eax by b
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f7 7/subop/divide-eax-edx-by *(ebp+0xc)
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$integer-divide:end:
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# . epilogue
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89/<- %esp 5/r32/ebp
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5d/pop-to-ebp
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c3/return
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