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[Bug middle-end/45379] [4.6 Regression] ~10% slowdown on test_fpu at revision 163278
- From: "dominiq at lps dot ens dot fr" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: 24 Aug 2010 14:33:24 -0000
- Subject: [Bug middle-end/45379] [4.6 Regression] ~10% slowdown on test_fpu at revision 163278
- References: <bug-45379-12313@http.gcc.gnu.org/bugzilla/>
- Reply-to: gcc-bugzilla at gcc dot gnu dot org
------- Comment #11 from dominiq at lps dot ens dot fr 2010-08-24 14:33 -------
Assembly for the inner loop
do i = 1, n
b(i,j) = b(i,j)-temp(i)*c
end do
with -Ofast
r163277
L38:
movsd (%rsi,%rax), %xmm0
addl $1, %ecx
movhpd 8(%rsi,%rax), %xmm0
movapd %xmm0, %xmm1
movapd (%rdi,%rax), %xmm0
mulpd %xmm3, %xmm1
subpd %xmm1, %xmm0
movapd %xmm0, (%rdi,%rax)
addq $16, %rax
cmpl $249, %ecx
jbe L38
r163519
L38:
movsd (%rdi,%rax), %xmm5
addl $1, %esi
movhpd 8(%rdi,%rax), %xmm5
movapd %xmm5, %xmm1
movsd (%rcx,%rax), %xmm5
mulpd %xmm3, %xmm1
movhpd 8(%rcx,%rax), %xmm5
movapd %xmm5, %xmm0
subpd %xmm1, %xmm0
movlpd %xmm0, (%rcx,%rax)
movhpd %xmm0, 8(%rcx,%rax)
addq $16, %rax
cmpl $249, %esi
jbe L38
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45379