[llvm] 9eb73f9 - Revert "[ConstantFold] Avoid creation of undesirable binop"

[Matthew Voss via llvm-commits]

Author: Matthew Voss
Date: 2023-07-26T12:56:31-07:00
New Revision: 9eb73f9c9d409f35151b0c1e01f1ed95808acd0c

URL: https://github.com/llvm/llvm-project/commit/9eb73f9c9d409f35151b0c1e01f1ed95808acd0c
DIFF: https://github.com/llvm/llvm-project/commit/9eb73f9c9d409f35151b0c1e01f1ed95808acd0c.diff

LOG: Revert "[ConstantFold] Avoid creation of undesirable binop"

This reverts commit 673a4671f3e8b7158d990f6456428175a6eac38c.

Depends on reverted commit 0cab8d20417c0e2ccc1ffc5505e080126f5de8e6.

That commit was reverted due to an LTO crash. I've put a reduced
test case here: https://github.com/llvm/llvm-project/issues/64114

Added: 
    

Modified: 
    llvm/lib/IR/ConstantFold.cpp
    llvm/test/Transforms/InstCombine/pr32686.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/IR/ConstantFold.cpp b/llvm/lib/IR/ConstantFold.cpp
index db1a83bf66204b..4c3325063c09d0 100644
--- a/llvm/lib/IR/ConstantFold.cpp
+++ b/llvm/lib/IR/ConstantFold.cpp
@@ -1084,9 +1084,7 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, Constant *C1,
   } else if (isa<ConstantInt>(C1)) {
     // If C1 is a ConstantInt and C2 is not, swap the operands.
     if (Instruction::isCommutative(Opcode))
-      return ConstantExpr::isDesirableBinOp(Opcode)
-                 ? ConstantExpr::get(Opcode, C2, C1)
-                 : ConstantFoldBinaryInstruction(Opcode, C2, C1);
+      return ConstantExpr::get(Opcode, C2, C1);
   }
 
   if (ConstantInt *CI1 = dyn_cast<ConstantInt>(C1)) {

diff  --git a/llvm/test/Transforms/InstCombine/pr32686.ll b/llvm/test/Transforms/InstCombine/pr32686.ll
index f981065bebeb80..acce81a603d2d0 100644
--- a/llvm/test/Transforms/InstCombine/pr32686.ll
+++ b/llvm/test/Transforms/InstCombine/pr32686.ll
@@ -8,9 +8,8 @@ define void @tinkywinky() {
 ; CHECK-LABEL: @tinkywinky(
 ; CHECK-NEXT:    [[PATATINO:%.*]] = load i8, ptr @a, align 1
 ; CHECK-NEXT:    [[TOBOOL_NOT:%.*]] = icmp eq i8 [[PATATINO]], 0
-; CHECK-NEXT:    [[TMP1:%.*]] = or i1 [[TOBOOL_NOT]], icmp ne (ptr @a, ptr @b)
-; CHECK-NEXT:    [[TMP2:%.*]] = zext i1 [[TMP1]] to i32
-; CHECK-NEXT:    [[OR1:%.*]] = or i32 [[TMP2]], 2
+; CHECK-NEXT:    [[TMP1:%.*]] = zext i1 [[TOBOOL_NOT]] to i32
+; CHECK-NEXT:    [[OR1:%.*]] = or i32 [[TMP1]], or (i32 zext (i1 icmp ne (ptr @a, ptr @b) to i32), i32 2)
 ; CHECK-NEXT:    store i32 [[OR1]], ptr @b, align 4
 ; CHECK-NEXT:    ret void
 ;