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#include <inttypes.h>
auto a(auto b) __attribute__ ((noinline));
auto a(auto b)
{
return b*1.5;
}
double test1(double in)
{
return a(in);
}
uint64_t test2(uint64_t in)
{
return a(in);
}
/*
https://godbolt.org/z/6ZQAnv
auto a<double>(double):
mulsd xmm0, QWORD PTR .LC0[rip]
ret
test1(double):
jmp auto a<double>(double)
auto a<unsigned long>(unsigned long):
test rdi, rdi
js .L5
pxor xmm0, xmm0
cvtsi2sd xmm0, rdi
mulsd xmm0, QWORD PTR .LC0[rip] # хули ты мне плавучего питуха в xmm0 возвращаешь?
ret
.L5:
mov rax, rdi
and edi, 1
pxor xmm0, xmm0
shr rax
or rax, rdi
cvtsi2sd xmm0, rax
addsd xmm0, xmm0
mulsd xmm0, QWORD PTR .LC0[rip]
ret
test2(unsigned long):
sub rsp, 8
call auto a<unsigned long>(unsigned long)
movsd xmm1, QWORD PTR .LC1[rip]
comisd xmm0, xmm1
jnb .L8
cvttsd2si rax, xmm0 # ну нахуй тут надо double в uint64_t конвертить
add rsp, 8 # почему это не делается в auto a<unsigned long>(unsigned long)
ret
.L8:
subsd xmm0, xmm1
add rsp, 8
cvttsd2si rax, xmm0
btc rax, 63
ret
.LC0:
.long 0
.long 1073217536
.LC1:
.long 0
.long 1138753536
*/
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