Chris Lattner
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f3edc09f9b
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Add a really quick hack at a machine code sinking pass, enabled with --enable-sinking.
It is missing validity checks, so it is known broken. However, it is powerful enough
to compile this contrived code:
void test1(int C, double A, double B, double *P) {
double Tmp = A*A+B*B;
*P = C ? Tmp : A;
}
into:
_test1:
movsd 8(%esp), %xmm0
cmpl $0, 4(%esp)
je LBB1_2 # entry
LBB1_1: # entry
movsd 16(%esp), %xmm1
mulsd %xmm1, %xmm1
mulsd %xmm0, %xmm0
addsd %xmm1, %xmm0
LBB1_2: # entry
movl 24(%esp), %eax
movsd %xmm0, (%eax)
ret
instead of:
_test1:
movsd 16(%esp), %xmm0
mulsd %xmm0, %xmm0
movsd 8(%esp), %xmm1
movapd %xmm1, %xmm2
mulsd %xmm2, %xmm2
addsd %xmm0, %xmm2
cmpl $0, 4(%esp)
je LBB1_2 # entry
LBB1_1: # entry
movapd %xmm2, %xmm1
LBB1_2: # entry
movl 24(%esp), %eax
movsd %xmm1, (%eax)
ret
woo.
llvm-svn: 45570
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2008-01-04 07:36:53 +00:00 |