Bruno Cardoso Lopes b11d8102cf Look through PHIs to find additional register sources ... - Teaches the ValueTracker in the PeepholeOptimizer to look through PHI instructions. - Add findNextSourceAndRewritePHI method to lookup into multiple sources returnted by the ValueTracker and rewrite PHIs with new sources. With these changes we can find more register sources and rewrite more copies to allow coaslescing of bitcast instructions. Hence, we eliminate unnecessary VR64 <-> GR64 copies in x86, but it could be extended to other archs by marking "isBitcast" on target specific instructions. The x86 example follows: A: psllq %mm1, %mm0 movd %mm0, %r9 jmp C B: por %mm1, %mm0 movd %mm0, %r9 jmp C C: movd %r9, %mm0 pshufw $238, %mm0, %mm0 Becomes: A: psllq %mm1, %mm0 jmp C B: por %mm1, %mm0 jmp C C: pshufw $238, %mm0, %mm0 Differential Revision: http://reviews.llvm.org/D11197 rdar://problem/20404526 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242295 91177308-0d34-0410-b5e6-96231b3b80d8		2015-07-15 15:35:23 +00:00
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llvm	Look through PHIs to find additional register sources	2015-07-15 15:35:23 +00:00
llvm-c	Add capability to get and set the personalitty function from the C API	2015-07-14 01:23:06 +00:00