[polly] r225818 - Use types of matching size when generating multi-dimensional address expressions

[Tobias Grosser]

Author: grosser
Date: Tue Jan 13 13:37:59 2015
New Revision: 225818

URL: http://llvm.org/viewvc/llvm-project?rev=225818&view=rev
Log:
Use types of matching size when generating multi-dimensional address expressions

This change ensures that the values that represent the array size of a
multi-dimensional access are correctly sign-extended when used to compute a
memory address used in the run-time alias check.

To make the test case more readable, we name the instructions that we generate.

Added:
    polly/trunk/test/Isl/CodeGen/multidim_alias_check.ll
Modified:
    polly/trunk/lib/CodeGen/IslExprBuilder.cpp

Modified: polly/trunk/lib/CodeGen/IslExprBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/lib/CodeGen/IslExprBuilder.cpp?rev=225818&r1=225817&r2=225818&view=diff
==============================================================================
--- polly/trunk/lib/CodeGen/IslExprBuilder.cpp (original)
+++ polly/trunk/lib/CodeGen/IslExprBuilder.cpp Tue Jan 13 13:37:59 2015
@@ -127,7 +127,8 @@ Value *IslExprBuilder::createAccessAddre
     if (!IndexOp)
       IndexOp = NextIndex;
     else
-      IndexOp = Builder.CreateAdd(IndexOp, NextIndex);
+      IndexOp =
+          Builder.CreateAdd(IndexOp, NextIndex, "polly.access.add." + BaseName);
 
     // For every but the last dimension multiply the size, for the last
     // dimension we can exit the loop.
@@ -135,9 +136,17 @@ Value *IslExprBuilder::createAccessAddre
       break;
 
     const SCEV *DimSCEV = SAI->getDimensionSize(u - 1);
-    Value *DimSize = Expander.expandCodeFor(DimSCEV, IndexOp->getType(),
+    Value *DimSize = Expander.expandCodeFor(DimSCEV, DimSCEV->getType(),
                                             Builder.GetInsertPoint());
-    IndexOp = Builder.CreateMul(IndexOp, DimSize);
+
+    Type *Ty = getWidestType(DimSize->getType(), IndexOp->getType());
+
+    if (Ty != IndexOp->getType())
+      IndexOp = Builder.CreateSExtOrTrunc(IndexOp, Ty,
+                                          "polly.access.sext." + BaseName);
+
+    IndexOp =
+        Builder.CreateMul(IndexOp, DimSize, "polly.access.mul." + BaseName);
   }
 
   Access = Builder.CreateGEP(Base, IndexOp, "polly.access." + BaseName);

Added: polly/trunk/test/Isl/CodeGen/multidim_alias_check.ll
URL: http://llvm.org/viewvc/llvm-project/polly/trunk/test/Isl/CodeGen/multidim_alias_check.ll?rev=225818&view=auto
==============================================================================
--- polly/trunk/test/Isl/CodeGen/multidim_alias_check.ll (added)
+++ polly/trunk/test/Isl/CodeGen/multidim_alias_check.ll Tue Jan 13 13:37:59 2015
@@ -0,0 +1,42 @@
+; RUN: opt %loadPolly -polly-codegen-isl -polly-delinearize < %s
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+; CHECK: %polly.access.sext.A = sext i32 %n to i64
+; CHECK: %polly.access.mul.A = mul i64 %polly.access.sext.A, %0
+; CHECK: %polly.access.add.A = add i64 %polly.access.mul.A, 1
+; CHECK: %polly.access.A = getelementptr double* %A, i64 %polly.access.add.A
+; CHECK: %polly.access.y = getelementptr double* %y, i64 0
+; CHECK: icmp ule double* %polly.access.A, %polly.access.y
+
+
+define void @init_array(i32 %n, double* %A, double* %y) {
+entry:
+  %add3 = add nsw i32 %n, 1
+  %tmp = zext i32 %add3 to i64
+  br label %for.body
+
+for.body:
+  %i.04 = phi i32 [ %inc39, %for.cond.loopexit ], [ 0, %entry ]
+  %arrayidx16 = getelementptr inbounds double* %y, i64 0
+  store double 1.0, double* %arrayidx16
+  %cmp251 = icmp slt i32 %n, 0
+  %inc39 = add nsw i32 %i.04, 1
+  br i1 %cmp251, label %for.cond.loopexit, label %for.body27
+
+for.body27:
+  %idxprom35 = sext i32 %i.04 to i64
+  %tmp1 = mul nsw i64 %idxprom35, %tmp
+  %arrayidx36.sum = add i64 0, %tmp1
+  %arrayidx37 = getelementptr inbounds double* %A, i64 %arrayidx36.sum
+  store double 1.0, double* %arrayidx37
+  br label %for.cond.loopexit
+
+for.cond.loopexit:
+  %cmp = icmp slt i32 %i.04, %n
+  br i1 %cmp, label %for.body, label %for.end40
+
+
+for.end40:
+  ret void
+}