[llvm] 6f51431 - [ConstantFold] Support ptrtoaddr in global alignment fold

[Nikita Popov via llvm-commits]

Author: Nikita Popov
Date: 2025-10-14T12:44:14+02:00
New Revision: 6f514313263da0fb4b6793689f6849e0f8fdb18b

URL: https://github.com/llvm/llvm-project/commit/6f514313263da0fb4b6793689f6849e0f8fdb18b
DIFF: https://github.com/llvm/llvm-project/commit/6f514313263da0fb4b6793689f6849e0f8fdb18b.diff

LOG: [ConstantFold] Support ptrtoaddr in global alignment fold

Treat it the same way as ptrtoint.

Added: 
    

Modified: 
    llvm/lib/IR/ConstantFold.cpp
    llvm/unittests/IR/ConstantsTest.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/IR/ConstantFold.cpp b/llvm/lib/IR/ConstantFold.cpp
index 3842b1afab05d..6a9ef2efa321f 100644
--- a/llvm/lib/IR/ConstantFold.cpp
+++ b/llvm/lib/IR/ConstantFold.cpp
@@ -741,7 +741,8 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, Constant *C1,
       assert(!CI2->isZero() && "And zero handled above");
       if (ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) {
         // If and'ing the address of a global with a constant, fold it.
-        if (CE1->getOpcode() == Instruction::PtrToInt &&
+        if ((CE1->getOpcode() == Instruction::PtrToInt ||
+             CE1->getOpcode() == Instruction::PtrToAddr) &&
             isa<GlobalValue>(CE1->getOperand(0))) {
           GlobalValue *GV = cast<GlobalValue>(CE1->getOperand(0));
 

diff  --git a/llvm/unittests/IR/ConstantsTest.cpp b/llvm/unittests/IR/ConstantsTest.cpp
index 54c7ddd003fc6..6376165cbe766 100644
--- a/llvm/unittests/IR/ConstantsTest.cpp
+++ b/llvm/unittests/IR/ConstantsTest.cpp
@@ -564,13 +564,17 @@ TEST(ConstantsTest, FoldGlobalVariablePtr) {
 
   Global->setAlignment(Align(4));
 
-  ConstantInt *TheConstant(ConstantInt::get(IntType, 2));
+  ConstantInt *TheConstant = ConstantInt::get(IntType, 2);
 
-  Constant *TheConstantExpr(ConstantExpr::getPtrToInt(Global.get(), IntType));
+  Constant *PtrToInt = ConstantExpr::getPtrToInt(Global.get(), IntType);
+  ASSERT_TRUE(
+      ConstantFoldBinaryInstruction(Instruction::And, PtrToInt, TheConstant)
+          ->isNullValue());
 
-  ASSERT_TRUE(ConstantFoldBinaryInstruction(Instruction::And, TheConstantExpr,
-                                            TheConstant)
-                  ->isNullValue());
+  Constant *PtrToAddr = ConstantExpr::getPtrToAddr(Global.get(), IntType);
+  ASSERT_TRUE(
+      ConstantFoldBinaryInstruction(Instruction::And, PtrToAddr, TheConstant)
+          ->isNullValue());
 }
 
 // Check that containsUndefOrPoisonElement and containsPoisonElement is working