Commit Graph

5 Commits

Author SHA1 Message Date
NAKAMURA Takumi
007b2b3c7e Relax expressions and add explicit triplets -linux and -win32.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126197 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-22 07:19:20 +00:00
Dan Gohman
cfbf0ed8b0 Apply the SSE dependence idiom for SSE unary operations to
SD instructions too, in addition to SS instructions. And
add a comment about it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108191 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-12 20:46:04 +00:00
Benjamin Kramer
a2938e7e5f Fix some tests that didn't test anything.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106954 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-26 20:05:06 +00:00
Evan Cheng
b1f4981333 Remove target attribute break-sse-dep. Instead, do not fold load into sse partial update instructions unless optimizing for size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91910 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-22 17:47:23 +00:00
Evan Cheng
400073d546 On recent Intel u-arch's, folding loads into some unary SSE instructions can
be non-optimal. To be precise, we should avoid folding loads if the instructions
only update part of the destination register, and the non-updated part is not
needed. e.g. cvtss2sd, sqrtss. Unfolding the load from these instructions breaks
the partial register dependency and it can improve performance. e.g.

movss (%rdi), %xmm0
cvtss2sd %xmm0, %xmm0

instead of
cvtss2sd (%rdi), %xmm0

An alternative method to break dependency is to clear the register first. e.g.
xorps %xmm0, %xmm0
cvtss2sd (%rdi), %xmm0


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91672 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-18 07:40:29 +00:00