From: Evgeny Astigeevich <evgeny.astigeevich@arm.com>
Date: Thu, 27 Jul 2017 12:49:27 +0000 (+0000)
Subject: [InlineCost, NFC] Change CallAnalyzer::isGEPFree to use TTI::getUserCost instead... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=e067bb531a93576aa0af97e720d5c8fd734868de;p=llvm

[InlineCost, NFC] Change CallAnalyzer::isGEPFree to use TTI::getUserCost instead of TTI::getGEPCost

Currently CallAnalyzer::isGEPFree uses TTI::getGEPCost to check if GEP is free.
TTI::getGEPCost cannot handle cases when GEPs participate in Def-Use dependencies
(see https://reviews.llvm.org/D31186 for example).
There is TTI::getUserCost which can calculate the cost more accurately by
taking dependencies into account.

Differential Revision: https://reviews.llvm.org/D33685


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309268 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Analysis/InlineCost.cpp b/lib/Analysis/InlineCost.cpp
index 35693666aa0..8be2ee7881a 100644
--- a/lib/Analysis/InlineCost.cpp
+++ b/lib/Analysis/InlineCost.cpp
@@ -348,15 +348,14 @@ bool CallAnalyzer::accumulateGEPOffset(GEPOperator &GEP, APInt &Offset) {
 ///
 /// Respects any simplified values known during the analysis of this callsite.
 bool CallAnalyzer::isGEPFree(GetElementPtrInst &GEP) {
-  SmallVector<Value *, 4> Indices;
+  SmallVector<Value *, 4> Operands;
+  Operands.push_back(GEP.getOperand(0));
   for (User::op_iterator I = GEP.idx_begin(), E = GEP.idx_end(); I != E; ++I)
     if (Constant *SimpleOp = SimplifiedValues.lookup(*I))
-       Indices.push_back(SimpleOp);
+       Operands.push_back(SimpleOp);
      else
-       Indices.push_back(*I);
-  return TargetTransformInfo::TCC_Free ==
-         TTI.getGEPCost(GEP.getSourceElementType(), GEP.getPointerOperand(),
-                        Indices);
+       Operands.push_back(*I);
+  return TargetTransformInfo::TCC_Free == TTI.getUserCost(&GEP, Operands);
 }
 
 bool CallAnalyzer::visitAlloca(AllocaInst &I) {