[PATCH] D39134: [X86][SSE] Add MOVHPSrm to domain tables

[Gadi Haber via Phabricator via llvm-commits]

gadi.haber added inline comments.


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Comment at: lib/Target/X86/X86InstrInfo.cpp:9446
   { X86::XORPSrr,    X86::XORPDrr,   X86::PXORrr    },
-  { X86::UNPCKLPDrm, X86::UNPCKLPDrm, X86::PUNPCKLQDQrm },
+  { X86::MOVHPSrm,   X86::UNPCKLPDrm, X86::PUNPCKLQDQrm },
   { X86::MOVLHPSrr,  X86::UNPCKLPDrr, X86::PUNPCKLQDQrr },
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craig.topper wrote:
> Does moving from MOVHPS to UNPCKLPD cause us to potentially access unaligned memory? MOVHPS doesn't have an alignment requirement, but UNPCKLPD does.
Yes.  64-bit memory operand has no restrictions while 128-bit (unpcklpd) always does in SSE except for movu* instructions.


Repository:
  rL LLVM

https://reviews.llvm.org/D39134