[llvm] r302905 - [NewGVN] Don't incorrectly reset the memory leader.

[Davide Italiano via llvm-commits]

Author: davide
Date: Fri May 12 10:22:45 2017
New Revision: 302905

URL: http://llvm.org/viewvc/llvm-project?rev=302905&view=rev
Log:
[NewGVN] Don't incorrectly reset the memory leader.

This code was missing a check for stores, so we were thinking the
congruency class didn't have any memory members, and reset the
memory leader.

Differential Revision:  https://reviews.llvm.org/D33056

Added:
    llvm/trunk/test/Transforms/NewGVN/pr32934.ll
Modified:
    llvm/trunk/lib/Transforms/Scalar/NewGVN.cpp

Modified: llvm/trunk/lib/Transforms/Scalar/NewGVN.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/NewGVN.cpp?rev=302905&r1=302904&r2=302905&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/NewGVN.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/NewGVN.cpp Fri May 12 10:22:45 2017
@@ -1409,7 +1409,7 @@ bool NewGVN::setMemoryClass(const Memory
         NewClass->memory_insert(MP);
         // This may have killed the class if it had no non-memory members
         if (OldClass->getMemoryLeader() == From) {
-          if (OldClass->memory_empty()) {
+          if (OldClass->definesNoMemory()) {
             OldClass->setMemoryLeader(nullptr);
           } else {
             OldClass->setMemoryLeader(getNextMemoryLeader(OldClass));

Added: llvm/trunk/test/Transforms/NewGVN/pr32934.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/NewGVN/pr32934.ll?rev=302905&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/NewGVN/pr32934.ll (added)
+++ llvm/trunk/test/Transforms/NewGVN/pr32934.ll Fri May 12 10:22:45 2017
@@ -0,0 +1,68 @@
+; RUN: opt -S -newgvn %s | FileCheck %s
+
+; CHECK: define void @tinkywinky() {
+; CHECK-NEXT: entry:
+; CHECK-NEXT:   %d = alloca i32, align 4
+; CHECK-NEXT:   store i32 0, i32* null, align 4
+; CHECK-NEXT:   br label %for.cond
+; CHECK: for.cond:                                         ; preds = %if.end, %entry
+; CHECK-NEXT:   %0 = load i32, i32* null, align 4
+; CHECK-NEXT:   %cmp = icmp slt i32 %0, 1
+; CHECK-NEXT:   br i1 %cmp, label %for.body, label %while.cond
+; CHECK: for.body:                                         ; preds = %for.cond
+; CHECK-NEXT:   %1 = load i32, i32* @a, align 4
+; CHECK-NEXT:   store i32 %1, i32* %d, align 4
+; CHECK-NEXT:   br label %L
+; CHECK: L:                                                ; preds = %if.then, %for.body
+; CHECK-NEXT:   %tobool = icmp ne i32 %1, 0
+; CHECK-NEXT:   br i1 %tobool, label %if.then, label %if.end
+; CHECK: if.then:                                          ; preds = %L
+; CHECK-NEXT:   call void (i8*, ...) @printf(i8* getelementptr inbounds ([2 x i8], [2 x i8]* @patatino, i32 0, i32 0))
+; CHECK-NEXT:   br label %L
+; CHECK: if.end:                                           ; preds = %L
+; CHECK-NEXT:   br label %for.cond
+; CHECK: while.cond:                                       ; preds = %while.body, %for.cond
+; CHECK-NEXT:   br i1 undef, label %while.body, label %while.end
+; CHECK: while.body:                                       ; preds = %while.cond
+; CHECK-NEXT:   call void (i8*, ...) @printf(i8* getelementptr inbounds ([2 x i8], [2 x i8]* @patatino, i32 0, i32 0))
+; CHECK-NEXT:   br label %while.cond
+; CHECK: while.end:
+; CHECK-NEXT:   %2 = load i32, i32* @a, align 4
+; CHECK-NEXT:   store i32 %2, i32* undef, align 4
+; CHECK-NEXT:   ret void
+
+ at a = external global i32, align 4
+ at patatino = external unnamed_addr constant [2 x i8], align 1
+define void @tinkywinky() {
+entry:
+  %d = alloca i32, align 4
+  store i32 0, i32* null, align 4
+  br label %for.cond
+for.cond:
+  %0 = load i32, i32* null, align 4
+  %cmp = icmp slt i32 %0, 1
+  br i1 %cmp, label %for.body, label %while.cond
+for.body:
+  %1 = load i32, i32* @a, align 4
+  store i32 %1, i32* %d, align 4
+  br label %L
+L:
+  %2 = load i32, i32* %d, align 4
+  %tobool = icmp ne i32 %2, 0
+  br i1 %tobool, label %if.then, label %if.end
+if.then:
+  call void (i8*, ...) @printf(i8* getelementptr inbounds ([2 x i8], [2 x i8]* @patatino, i32 0, i32 0))
+  br label %L
+if.end:
+  br label %for.cond
+while.cond:
+  br i1 undef, label %while.body, label %while.end
+while.body:
+  call void (i8*, ...) @printf(i8* getelementptr inbounds ([2 x i8], [2 x i8]* @patatino, i32 0, i32 0))
+  br label %while.cond
+while.end:
+  %3 = load i32, i32* @a, align 4
+  store i32 %3, i32* undef, align 4
+  ret void
+}
+declare void @printf(i8*, ...) #1