[llvm] b37476f - PHITransAddr: Avoid looking at constant use lists (#134689)

[Matt Arsenault via llvm-commits]

Author: Matt Arsenault
Date: 2025-04-13T16:58:57+02:00
New Revision: b37476f99c37a9edf48684d82dde745d9e0df957

URL: https://github.com/llvm/llvm-project/commit/b37476f99c37a9edf48684d82dde745d9e0df957
DIFF: https://github.com/llvm/llvm-project/commit/b37476f99c37a9edf48684d82dde745d9e0df957.diff

LOG: PHITransAddr: Avoid looking at constant use lists (#134689)

Avoids asserts in GVN

Added: 
    

Modified: 
    llvm/lib/Analysis/PHITransAddr.cpp
    llvm/test/Transforms/GVN/pr65447.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Analysis/PHITransAddr.cpp b/llvm/lib/Analysis/PHITransAddr.cpp
index e42113db42781..276708c2ebf77 100644
--- a/llvm/lib/Analysis/PHITransAddr.cpp
+++ b/llvm/lib/Analysis/PHITransAddr.cpp
@@ -224,6 +224,9 @@ Value *PHITransAddr::translateSubExpr(Value *V, BasicBlock *CurBB,
 
     // Scan to see if we have this GEP available.
     Value *APHIOp = GEPOps[0];
+    if (isa<ConstantData>(APHIOp))
+      return nullptr;
+
     for (User *U : APHIOp->users()) {
       if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(U))
         if (GEPI->getType() == GEP->getType() &&

diff  --git a/llvm/test/Transforms/GVN/pr65447.ll b/llvm/test/Transforms/GVN/pr65447.ll
index 1b951e907e822..1fa3811a3a81d 100644
--- a/llvm/test/Transforms/GVN/pr65447.ll
+++ b/llvm/test/Transforms/GVN/pr65447.ll
@@ -2,29 +2,98 @@
 ; RUN: opt -S -passes=gvn < %s | FileCheck %s
 
 ; Make sure deduplicated phi nodes are removed from the VN map.
-define i64 @f() {
-; CHECK-LABEL: define i64 @f() {
+define i64 @f2(ptr %arg) {
+; CHECK-LABEL: define i64 @f2(
+; CHECK-SAME: ptr [[ARG:%.*]]) {
+; CHECK-NEXT:  BB:
+; CHECK-NEXT:    store i1 false, ptr [[ARG]], align 1
+; CHECK-NEXT:    br label [[BB2D:%.*]]
+; CHECK:       BB2a:
+; CHECK-NEXT:    br label [[BB2B:%.*]]
+; CHECK:       BB2b:
+; CHECK-NEXT:    br label [[BB2C:%.*]]
+; CHECK:       BB2c:
+; CHECK-NEXT:    [[AZ2:%.*]] = phi i1 [ true, [[BB2B]] ], [ [[AZ:%.*]], [[BB2D]] ]
+; CHECK-NEXT:    [[DOTPHI_TRANS_INSERT:%.*]] = sext i1 [[AZ2]] to i64
+; CHECK-NEXT:    [[GEP2_PHI_TRANS_INSERT:%.*]] = getelementptr i1, ptr [[ARG]], i64 [[DOTPHI_TRANS_INSERT]]
+; CHECK-NEXT:    [[L93_PRE:%.*]] = load i1, ptr [[GEP2_PHI_TRANS_INSERT]], align 1
+; CHECK-NEXT:    br label [[BB2D]]
+; CHECK:       BB2d:
+; CHECK-NEXT:    [[AZ]] = phi i1 [ [[AZ2]], [[BB2C]] ], [ false, [[BB:%.*]] ]
+; CHECK-NEXT:    [[L93:%.*]] = phi i1 [ [[L93_PRE]], [[BB2C]] ], [ false, [[BB]] ]
+; CHECK-NEXT:    [[TMP0:%.*]] = sext i1 [[AZ]] to i64
+; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr i1, ptr [[ARG]], i64 [[TMP0]]
+; CHECK-NEXT:    store i1 [[AZ]], ptr [[ARG]], align 2
+; CHECK-NEXT:    br i1 [[L93]], label [[BB2C]], label [[BB1E:%.*]]
+; CHECK:       BB1e:
+; CHECK-NEXT:    br i1 [[AZ]], label [[BB2F:%.*]], label [[BB4:%.*]]
+; CHECK:       BB2f:
+; CHECK-NEXT:    store i1 true, ptr [[ARG]], align 2
+; CHECK-NEXT:    br label [[BB2B]]
+; CHECK:       BB4:
+; CHECK-NEXT:    br label [[BB4]]
+;
+BB:
+  store i1 false, ptr %arg, align 1
+  br label %BB2d
+
+BB2a: ; No predecessors!
+  br label %BB2b
+
+BB2b:       ; preds = %BB2f, %BB2a
+  br label %BB2c
+
+BB2c:                     ; preds = %BB2d, %BB2b
+  %0 = phi i1 [ true, %BB2b ], [ %1, %BB2d ]
+  br label %BB2d
+
+BB2d:                              ; preds = %BB2c, %BB
+  %1 = phi i1 [ %0, %BB2c ], [ false, %BB ]
+  %2 = sext i1 %1 to i64
+  %gep2 = getelementptr i1, ptr %arg, i64 %2
+  %L93 = load i1, ptr %gep2, align 1
+  %Az = load i1, ptr %arg, align 2
+  store i1 %1, ptr %arg, align 2
+  br i1 %L93, label %BB2c, label %BB1e
+
+BB1e:                                        ; preds = %BB2d
+  br i1 %Az, label %BB2f, label %BB4
+
+BB2f:                                ; preds = %BB1e
+  store i1 true, ptr %arg, align 2
+  br label %BB2b
+
+BB4:                                              ; preds = %BB1e, %BB4
+  br label %BB4
+
+; uselistorder directives
+  uselistorder label %BB4, { 1, 0 }
+}
+
+; Make sure deduplicated phi nodes are removed from the VN map. Make
+; sure there is no assert on attempt to use ConstantData use lists.
+define i64 @f_null() {
+; CHECK-LABEL: define i64 @f_null() {
 ; CHECK-NEXT:  BB:
 ; CHECK-NEXT:    store i1 false, ptr null, align 1
 ; CHECK-NEXT:    br label [[BB2D:%.*]]
 ; CHECK:       BB2a:
 ; CHECK-NEXT:    br label [[BB2B:%.*]]
 ; CHECK:       BB2b:
-; CHECK-NEXT:    [[L93_PRE_PRE:%.*]] = load i1, ptr inttoptr (i64 -1 to ptr), align 1
 ; CHECK-NEXT:    br label [[BB2C:%.*]]
 ; CHECK:       BB2c:
-; CHECK-NEXT:    [[L93_PRE:%.*]] = phi i1 [ [[L93_PRE_PRE]], [[BB2B]] ], [ true, [[BB2D]] ]
 ; CHECK-NEXT:    [[AZ2:%.*]] = phi i1 [ true, [[BB2B]] ], [ [[AZ:%.*]], [[BB2D]] ]
 ; CHECK-NEXT:    [[DOTPHI_TRANS_INSERT:%.*]] = sext i1 [[AZ2]] to i64
 ; CHECK-NEXT:    [[GEP2_PHI_TRANS_INSERT:%.*]] = getelementptr i1, ptr null, i64 [[DOTPHI_TRANS_INSERT]]
+; CHECK-NEXT:    [[L93_PRE:%.*]] = load i1, ptr [[GEP2_PHI_TRANS_INSERT]], align 1
 ; CHECK-NEXT:    br label [[BB2D]]
 ; CHECK:       BB2d:
-; CHECK-NEXT:    [[L93_PRE5:%.*]] = phi i1 [ [[L93_PRE]], [[BB2C]] ], [ false, [[BB:%.*]] ]
-; CHECK-NEXT:    [[AZ]] = phi i1 [ [[AZ2]], [[BB2C]] ], [ false, [[BB]] ]
+; CHECK-NEXT:    [[AZ]] = phi i1 [ [[AZ2]], [[BB2C]] ], [ false, [[BB:%.*]] ]
+; CHECK-NEXT:    [[L93:%.*]] = phi i1 [ [[L93_PRE]], [[BB2C]] ], [ false, [[BB]] ]
 ; CHECK-NEXT:    [[TMP0:%.*]] = sext i1 [[AZ]] to i64
 ; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr i1, ptr null, i64 [[TMP0]]
 ; CHECK-NEXT:    store i1 [[AZ]], ptr null, align 2
-; CHECK-NEXT:    br i1 [[L93_PRE5]], label [[BB2C]], label [[BB1E:%.*]]
+; CHECK-NEXT:    br i1 [[L93]], label [[BB2C]], label [[BB1E:%.*]]
 ; CHECK:       BB1e:
 ; CHECK-NEXT:    br i1 [[AZ]], label [[BB2F:%.*]], label [[BB4:%.*]]
 ; CHECK:       BB2f: