[PATCH] D59787: [ARM] Implement TTI::getMemcpyCost

[Dave Green via Phabricator via llvm-commits]

dmgreen added inline comments.


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Comment at: lib/Target/ARM/ARMTargetTransformInfo.cpp:412
+  // is more expensive than 'TCC_Expensive = 4'.
+  const unsigned LibCallCost = 6;
+
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Can you explain why this is more than 6? I would imagine it would be something like 4; 1 (for the call) + a few for argument setup.


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Comment at: lib/Target/ARM/ARMTargetTransformInfo.cpp:436
+                                        MI->getDestAddressSpace(),
+                                        MI->getSourceAddressSpace(), *F))
+    return MemOps.size() * 2;
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Does this need to be clang-formatted?


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Comment at: test/Analysis/CostModel/ARM/memcpy.ll:373
+; ldrh r1, [r1]
+; strh r1, [r0]
+;
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Is it worth adding a few strict-align tests too?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D59787/new/

https://reviews.llvm.org/D59787