[llvm] 5d63903 - [SCCP] Check that load/store and global type match

[Nikita Popov via llvm-commits]

Author: Nikita Popov
Date: 2022-02-11T11:01:18+01:00
New Revision: 5d639034652dda9659e45ffd863e5052ab8ffc4a

URL: https://github.com/llvm/llvm-project/commit/5d639034652dda9659e45ffd863e5052ab8ffc4a
DIFF: https://github.com/llvm/llvm-project/commit/5d639034652dda9659e45ffd863e5052ab8ffc4a.diff

LOG: [SCCP] Check that load/store and global type match

SCCP requires that the load/store type and global type are the
same (it does not support bitcasts of tracked globals). With
typed pointers this was implicitly enforced.

Added: 
    llvm/test/Transforms/SCCP/opaque-ptr.ll

Modified: 
    llvm/lib/Analysis/ValueLatticeUtils.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Analysis/ValueLatticeUtils.cpp b/llvm/lib/Analysis/ValueLatticeUtils.cpp
index 53638c351f722..2bcb4d5b0e6b1 100644
--- a/llvm/lib/Analysis/ValueLatticeUtils.cpp
+++ b/llvm/lib/Analysis/ValueLatticeUtils.cpp
@@ -29,12 +29,13 @@ bool llvm::canTrackGlobalVariableInterprocedurally(GlobalVariable *GV) {
       !GV->hasDefinitiveInitializer())
     return false;
   return all_of(GV->users(), [&](User *U) {
-    // Currently all users of a global variable have to be none-volatile loads
-    // or stores and the global cannot be stored itself.
+    // Currently all users of a global variable have to be non-volatile loads
+    // or stores of the global type, and the global cannot be stored itself.
     if (auto *Store = dyn_cast<StoreInst>(U))
-      return Store->getValueOperand() != GV && !Store->isVolatile();
+      return Store->getValueOperand() != GV && !Store->isVolatile() &&
+             Store->getValueOperand()->getType() == GV->getValueType();
     if (auto *Load = dyn_cast<LoadInst>(U))
-      return !Load->isVolatile();
+      return !Load->isVolatile() && Load->getType() == GV->getValueType();
 
     return false;
   });

diff  --git a/llvm/test/Transforms/SCCP/opaque-ptr.ll b/llvm/test/Transforms/SCCP/opaque-ptr.ll
new file mode 100644
index 0000000000000..9306ec397cf0e
--- /dev/null
+++ b/llvm/test/Transforms/SCCP/opaque-ptr.ll
@@ -0,0 +1,23 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -S -ipsccp -opaque-pointers < %s | FileCheck %s
+
+ at g1 = internal global i32 1
+ at g2 = internal global i32 1
+
+define i8 @test1() {
+; CHECK-LABEL: @test1(
+; CHECK-NEXT:    [[V:%.*]] = load i8, ptr @g1, align 1
+; CHECK-NEXT:    ret i8 [[V]]
+;
+  %v = load i8, ptr @g1
+  ret i8 %v
+}
+
+define void @test2() {
+; CHECK-LABEL: @test2(
+; CHECK-NEXT:    store i8 2, ptr @g2, align 1
+; CHECK-NEXT:    ret void
+;
+  store i8 2, ptr @g2
+  ret void
+}