[llvm-commits] [llvm] r112878 - in /llvm/trunk: lib/Transforms/Scalar/LICM.cpp test/Transforms/LICM/scalar_promote.ll

[Chris Lattner]

Author: lattner
Date: Thu Sep  2 17:19:10 2010
New Revision: 112878

URL: http://llvm.org/viewvc/llvm-project?rev=112878&view=rev
Log:
fix more AST updating bugs, correcting miscompilation in PR8041

Modified:
    llvm/trunk/lib/Transforms/Scalar/LICM.cpp
    llvm/trunk/test/Transforms/LICM/scalar_promote.ll

Modified: llvm/trunk/lib/Transforms/Scalar/LICM.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/LICM.cpp?rev=112878&r1=112877&r2=112878&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/LICM.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/LICM.cpp Thu Sep  2 17:19:10 2010
@@ -583,7 +583,7 @@
   // Update CurAST for NewPHIs if I had pointer type.
   if (I.getType()->isPointerTy())
     for (unsigned i = 0, e = NewPHIs.size(); i != e; ++i)
-      CurAST->copyValue(NewPHIs[i], &I);
+      CurAST->copyValue(&I, NewPHIs[i]);
   
   // Finally, remove the instruction from CurAST.  It is no longer in the loop.
   CurAST->deleteValue(&I);
@@ -843,7 +843,9 @@
   // inserting PHI nodes as necessary.
   for (unsigned i = 0, e = LiveInLoads.size(); i != e; ++i) {
     LoadInst *ALoad = LiveInLoads[i];
-    ALoad->replaceAllUsesWith(SSA.GetValueInMiddleOfBlock(ALoad->getParent()));
+    Value *NewVal = SSA.GetValueInMiddleOfBlock(ALoad->getParent());
+    ALoad->replaceAllUsesWith(NewVal);
+    CurAST->copyValue(ALoad, NewVal);
   }
   
   // Now that everything is rewritten, delete the old instructions from the body

Modified: llvm/trunk/test/Transforms/LICM/scalar_promote.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/LICM/scalar_promote.ll?rev=112878&r1=112877&r2=112878&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/LICM/scalar_promote.ll (original)
+++ llvm/trunk/test/Transforms/LICM/scalar_promote.ll Thu Sep  2 17:19:10 2010
@@ -71,3 +71,50 @@
 	ret void
 }
 
+; PR8041
+define void @test4(i8* %x, i8 %n) {
+; CHECK: @test4
+  %handle1 = alloca i8*
+  %handle2 = alloca i8*
+  store i8* %x, i8** %handle1
+  br label %loop
+
+loop:
+  %tmp = getelementptr i8* %x, i64 8
+  store i8* %tmp, i8** %handle2
+  br label %subloop
+
+subloop:
+  %count = phi i8 [ 0, %loop ], [ %nextcount, %subloop ]
+  %offsetx2 = load i8** %handle2
+  store i8 %n, i8* %offsetx2
+  %newoffsetx2 = getelementptr i8* %offsetx2, i64 -1
+  store i8* %newoffsetx2, i8** %handle2
+  %nextcount = add i8 %count, 1
+  %innerexitcond = icmp sge i8 %nextcount, 8
+  br i1 %innerexitcond, label %innerexit, label %subloop
+
+; Should have promoted 'handle2' accesses.
+; CHECK: subloop:
+; CHECK-NEXT: phi i8* [
+; CHECK-NEXT: %count = phi i8 [
+; CHECK-NEXT: store i8 %n
+; CHECK-NOT: store
+; CHECK: br i1
+
+innerexit:
+  %offsetx1 = load i8** %handle1
+  %val = load i8* %offsetx1
+  %cond = icmp eq i8 %val, %n
+  br i1 %cond, label %exit, label %loop
+
+; Should not have promoted offsetx1 loads.
+; CHECK: innerexit:
+; CHECK: %val = load i8* %offsetx1
+; CHECK: %cond = icmp eq i8 %val, %n
+; CHECK: br i1 %cond, label %exit, label %loop
+
+exit:
+  ret void
+}
+