[llvm] 23caf9e - Local: fix debug output of replaceDominatedUsesWith()

[Ramkumar Ramachandra via llvm-commits]

Author: Ramkumar Ramachandra
Date: 2023-07-27T13:23:38+01:00
New Revision: 23caf9e9e70464340ca490a0c75af0eeadcb981c

URL: https://github.com/llvm/llvm-project/commit/23caf9e9e70464340ca490a0c75af0eeadcb981c
DIFF: https://github.com/llvm/llvm-project/commit/23caf9e9e70464340ca490a0c75af0eeadcb981c.diff

LOG: Local: fix debug output of replaceDominatedUsesWith()

The debug output of replaceDominatedUsesWith() prints incorrect
information, and the user is left confused about what exactly was
replaced. Fix this.

Differential Revision: https://reviews.llvm.org/D156318

Added: 
    llvm/test/Transforms/Util/local-dbg-print.ll

Modified: 
    llvm/lib/Transforms/Utils/Local.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index f153ace5d3fc53..ff1facb3d797e4 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -2896,9 +2896,10 @@ static unsigned replaceDominatedUsesWith(Value *From, Value *To,
   for (Use &U : llvm::make_early_inc_range(From->uses())) {
     if (!Dominates(Root, U))
       continue;
+    LLVM_DEBUG(dbgs() << "Replace dominated use of '";
+               From->printAsOperand(dbgs());
+               dbgs() << "' with " << *To << " in " << *U.getUser() << "\n");
     U.set(To);
-    LLVM_DEBUG(dbgs() << "Replace dominated use of '" << From->getName()
-                      << "' as " << *To << " in " << *U << "\n");
     ++Count;
   }
   return Count;

diff  --git a/llvm/test/Transforms/Util/local-dbg-print.ll b/llvm/test/Transforms/Util/local-dbg-print.ll
new file mode 100644
index 00000000000000..ba20599d2d72ec
--- /dev/null
+++ b/llvm/test/Transforms/Util/local-dbg-print.ll
@@ -0,0 +1,34 @@
+; REQUIRES: asserts
+; RUN: opt -passes=gvn -debug-only=local -disable-output 2>&1 < %s | FileCheck %s
+
+define void @replaceDominatedUsesWith_debug(ptr nocapture writeonly %a, i32 %beam) {
+; CHECK: Replace dominated use of 'i64 %indvars.iv' with   %0 = zext i32 %beam to i64 in   %1 = shl nuw nsw i64 %indvars.iv, 1
+entry:
+  %0 = zext i32 %beam to i64
+  br label %for.body
+
+for.cond.cleanup:                                 ; preds = %for.inc
+  ret void
+
+for.body:                                         ; preds = %entry, %for.inc
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.inc ]
+  %cmp1 = icmp eq i64 %indvars.iv, %0
+  br i1 %cmp1, label %if.then, label %if.else
+
+if.then:                                          ; preds = %for.body
+  %1 = shl nuw nsw i64 %indvars.iv, 1
+  %arrayidx = getelementptr inbounds i32, ptr %a, i64 %1
+  store i32 0, ptr %arrayidx, align 4
+  br label %for.inc
+
+if.else:                                          ; preds = %for.body
+  %2 = shl nuw nsw i64 %indvars.iv, 1
+  %arrayidx4 = getelementptr inbounds i32, ptr %a, i64 %2
+  store i32 1, ptr %arrayidx4, align 4
+  br label %for.inc
+
+for.inc:                                          ; preds = %if.then, %if.else
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %exitcond.not = icmp eq i64 %indvars.iv.next, 10000
+  br i1 %exitcond.not, label %for.cond.cleanup, label %for.body
+}