Rewrite Cop1.cpp to conform to strict-aliasing rules #214
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Souzooka
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…ict-aliasing rules
Souzooka
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this is actually slightly broken right now but someone broke the autotests and I can't find the bug
Souzooka
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Cloudef
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Oct 17, 2019
| { | ||
| switch(value & 0x7F800000) | ||
| uint32_t test; | ||
| memcpy(&test, &value, sizeof(float)); |
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Valid in C99 (and above) and C++11 (and above)
| { | ||
| gpr[dest].u = gpr[source].u ^ 0x80000000; | ||
| gpr[dest] = -gpr[source]; |
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NEG only flips the sign bit, not the whole value, not sure how this would behave, and what if the original value is already negative? surely doing - will keep it the same, which is not a negation
| temp.f = sqrt(fabs(convert(gpr[reg2].u))); | ||
| gpr[dest].f = convert(gpr[reg1].u) / convert(temp.u); | ||
| float temp = sqrtf(fabsf(convert(gpr[reg2]))); | ||
| gpr[dest] = convert(gpr[reg1]) / convert(temp); |
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why not use ureg1/2 ?
| control.i = true; | ||
| control.si = true; | ||
| } | ||
|
|
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| gpr[dest].f = sqrt(fabs(convert(gpr[source].u))); | ||
| gpr[dest] = sqrtf(fabsf(convert(gpr[source]))); |
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why not use usource?
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also why only memcpy back the dest on zero and not in normal operation?
| } | ||
| else | ||
| gpr[dest].f = convert(numerator) / convert(denominator); | ||
| gpr[dest] = convert(gpr[reg1]) / convert(gpr[reg2]); |
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numerator / denominator
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…ict-aliasing rules