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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48064 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2008-03-09 01:08:22 +00:00
parent 62098040a1
commit f68cbceb17
1 changed files with 37 additions and 0 deletions
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37
lib/Target/X86/README-SSE.txt
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@ -782,3 +782,40 @@ just a matter of matching (scalar_to_vector (load x)) to movd.
//===---------------------------------------------------------------------===//
These two functions should compile to identical code on x86-32:
define <2 x i64> @test2(i64 %arg) {
entry:
%A = and i64 %arg, 1234567
%B = insertelement <2 x i64> undef, i64 %A, i32 0
ret <2 x i64> %B
}
define <2 x i64> @test2(i64 %arg) {
entry:
%A = and i64 %arg, 1234567
%B = insertelement <2 x i64> zeroinitializer, i64 %A, i32 0
ret <2 x i64> %B
}
The later compiles to:
_test2:
movl $1234567, %eax
andl 4(%esp), %eax
movd %eax, %xmm0
ret
the former compiles to:
_test2:
subl $28, %esp
movl $1234567, %eax
andl 32(%esp), %eax
movl %eax, (%esp)
movl $0, 4(%esp)
movaps (%esp), %xmm0
addl $28, %esp
ret
//===---------------------------------------------------------------------===//