[llvm] [InstCombine] Combine and->cmp->sel->or-disjoint into and->mul (PR #135274)

Jeffrey Byrnes via llvm-commits llvm-commits at lists.llvm.org
Fri May 2 15:01:22 PDT 2025


https://github.com/jrbyrnes updated https://github.com/llvm/llvm-project/pull/135274

>From f6baccff647cd73aaca4647b8476ceb92d6c6abb Mon Sep 17 00:00:00 2001
From: Jeffrey Byrnes <Jeffrey.Byrnes at amd.com>
Date: Thu, 24 Apr 2025 13:44:36 -0700
Subject: [PATCH 1/3] [InstCombine] Combine and->cmp->sel->or-disjoint into
 and->mul

Change-Id: I389bba8bec937236e16eecc87688440878469472
---
 .../InstCombine/InstCombineAndOrXor.cpp       |  48 +++
 .../test/Transforms/InstCombine/or-bitmask.ll | 328 ++++++++++++++++++
 2 files changed, 376 insertions(+)
 create mode 100644 llvm/test/Transforms/InstCombine/or-bitmask.ll

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
index b74bce391aa56..18d3f551adef4 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
@@ -3641,6 +3641,54 @@ Instruction *InstCombinerImpl::visitOr(BinaryOperator &I) {
             foldAddLikeCommutative(I.getOperand(1), I.getOperand(0),
                                    /*NSW=*/true, /*NUW=*/true))
       return R;
+
+    Value *Cond0 = nullptr, *Cond1 = nullptr;
+    const APInt *Op0Eq = nullptr, *Op0Ne = nullptr;
+    const APInt *Op1Eq = nullptr, *Op1Ne = nullptr;
+
+    //  (!(A & N) ? 0 : N * C) + (!(A & M) ? 0 : M * C) -> A & (N + M) * C
+    if (match(I.getOperand(0),
+              m_Select(m_Value(Cond0), m_APInt(Op0Eq), m_APInt(Op0Ne))) &&
+        match(I.getOperand(1),
+              m_Select(m_Value(Cond1), m_APInt(Op1Eq), m_APInt(Op1Ne)))) {
+      CmpPredicate Pred0, Pred1;
+
+      auto LHSDecompose =
+          decomposeBitTest(Cond0, /*LookThruTrunc=*/true,
+                           /*AllowNonZeroC=*/false, /*DecomposeAnd=*/true);
+      auto RHSDecompose =
+          decomposeBitTest(Cond1, /*LookThruTrunc=*/true,
+                           /*AllowNonZeroC=*/false, /*DecomposeAnd=*/true);
+
+      if (LHSDecompose && RHSDecompose && LHSDecompose->X == RHSDecompose->X &&
+          (ICmpInst::isEquality(LHSDecompose->Pred)) &&
+          !RHSDecompose->Mask.isNegative() &&
+          !LHSDecompose->Mask.isNegative() && RHSDecompose->Mask.isPowerOf2() &&
+          LHSDecompose->Mask.isPowerOf2() &&
+          LHSDecompose->Mask != RHSDecompose->Mask &&
+          LHSDecompose->C.isZero() && RHSDecompose->C.isZero()) {
+        if (LHSDecompose->Pred == ICmpInst::ICMP_NE)
+          std::swap(Op0Eq, Op0Ne);
+        if (RHSDecompose->Pred == ICmpInst::ICMP_NE)
+          std::swap(Op1Eq, Op1Ne);
+
+        if (Op0Ne->isStrictlyPositive() && Op1Ne->isStrictlyPositive() &&
+            Op0Eq->isZero() && Op1Eq->isZero() &&
+            Op0Ne->urem(LHSDecompose->Mask).isZero() &&
+            Op1Ne->urem(RHSDecompose->Mask).isZero() &&
+            Op0Ne->udiv(LHSDecompose->Mask) ==
+                Op1Ne->udiv(RHSDecompose->Mask)) {
+          auto NewAnd = Builder.CreateAnd(
+              LHSDecompose->X,
+              ConstantInt::get(LHSDecompose->X->getType(),
+                               (LHSDecompose->Mask + RHSDecompose->Mask)));
+
+          return BinaryOperator::CreateMul(
+              NewAnd, ConstantInt::get(NewAnd->getType(),
+                                       Op0Ne->udiv(LHSDecompose->Mask)));
+        }
+      }
+    }
   }
 
   Value *X, *Y;
diff --git a/llvm/test/Transforms/InstCombine/or-bitmask.ll b/llvm/test/Transforms/InstCombine/or-bitmask.ll
new file mode 100644
index 0000000000000..18acc42f2dc40
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/or-bitmask.ll
@@ -0,0 +1,328 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -passes=instcombine -S | FileCheck %s --check-prefixes=CHECK,CONSTVEC
+; RUN: opt < %s -passes=instcombine -S -use-constant-int-for-fixed-length-splat | FileCheck %s --check-prefixes=CHECK,CONSTSPLAT
+
+define i32 @add_select_cmp_and1(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_and1(
+; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[IN:%.*]], 3
+; CHECK-NEXT:    [[OUT:%.*]] = mul nuw nsw i32 [[TMP1]], 72
+; CHECK-NEXT:    ret i32 [[OUT]]
+;
+  %bitop0 = and i32 %in, 1
+  %cmp0 = icmp eq i32 %bitop0, 0
+  %bitop1 = and i32 %in, 2
+  %cmp1 = icmp eq i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 0, i32 72
+  %sel1 = select i1 %cmp1, i32 0, i32 144
+  %out = or disjoint i32 %sel0, %sel1
+  ret i32 %out
+}
+
+define i32 @add_select_cmp_and2(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_and2(
+; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[IN:%.*]], 5
+; CHECK-NEXT:    [[OUT:%.*]] = mul nuw nsw i32 [[TMP1]], 72
+; CHECK-NEXT:    ret i32 [[OUT]]
+;
+  %bitop0 = and i32 %in, 1
+  %cmp0 = icmp eq i32 %bitop0, 0
+  %bitop1 = and i32 %in, 4
+  %cmp1 = icmp eq i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 0, i32 72
+  %sel1 = select i1 %cmp1, i32 0, i32 288
+  %out = or disjoint i32 %sel0, %sel1
+  ret i32 %out
+}
+
+define i32 @add_select_cmp_and3(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_and3(
+; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[IN:%.*]], 3
+; CHECK-NEXT:    [[TEMP:%.*]] = mul nuw nsw i32 [[TMP1]], 72
+; CHECK-NEXT:    [[BITOP2:%.*]] = and i32 [[IN]], 4
+; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq i32 [[BITOP2]], 0
+; CHECK-NEXT:    [[SEL2:%.*]] = select i1 [[CMP2]], i32 0, i32 288
+; CHECK-NEXT:    [[OUT:%.*]] = or disjoint i32 [[TEMP]], [[SEL2]]
+; CHECK-NEXT:    ret i32 [[OUT]]
+;
+  %bitop0 = and i32 %in, 1
+  %cmp0 = icmp eq i32 %bitop0, 0
+  %bitop1 = and i32 %in, 2
+  %cmp1 = icmp eq i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 0, i32 72
+  %sel1 = select i1 %cmp1, i32 0, i32 144
+  %temp = or disjoint i32 %sel0, %sel1
+  %bitop2 = and i32 %in, 4
+  %cmp2 = icmp eq i32 %bitop2, 0
+  %sel2 = select i1 %cmp2, i32 0, i32 288
+  %out = or disjoint i32 %temp, %sel2
+  ret i32 %out
+}
+
+define i32 @add_select_cmp_and4(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_and4(
+; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[IN:%.*]], 3
+; CHECK-NEXT:    [[OUT:%.*]] = mul nuw nsw i32 [[TMP1]], 72
+; CHECK-NEXT:    [[TMP2:%.*]] = and i32 [[IN]], 12
+; CHECK-NEXT:    [[TEMP3:%.*]] = mul nuw nsw i32 [[TMP2]], 72
+; CHECK-NEXT:    [[OUT1:%.*]] = or disjoint i32 [[OUT]], [[TEMP3]]
+; CHECK-NEXT:    ret i32 [[OUT1]]
+;
+  %bitop0 = and i32 %in, 1
+  %cmp0 = icmp eq i32 %bitop0, 0
+  %bitop1 = and i32 %in, 2
+  %cmp1 = icmp eq i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 0, i32 72
+  %sel1 = select i1 %cmp1, i32 0, i32 144
+  %temp = or disjoint i32 %sel0, %sel1
+  %bitop2 = and i32 %in, 4
+  %cmp2 = icmp eq i32 %bitop2, 0
+  %bitop3 = and i32 %in, 8
+  %cmp3 = icmp eq i32 %bitop3, 0
+  %sel2 = select i1 %cmp2, i32 0, i32 288
+  %sel3 = select i1 %cmp3, i32 0, i32 576
+  %temp2 = or disjoint i32 %sel2, %sel3
+  %out = or disjoint i32 %temp, %temp2
+  ret i32 %out
+}
+
+define i32 @add_select_cmp_and_pred1(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_and_pred1(
+; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[IN:%.*]], 3
+; CHECK-NEXT:    [[OUT:%.*]] = mul nuw nsw i32 [[TMP1]], 72
+; CHECK-NEXT:    ret i32 [[OUT]]
+;
+  %bitop0 = and i32 %in, 1
+  %cmp0 = icmp ne i32 %bitop0, 0
+  %bitop1 = and i32 %in, 2
+  %cmp1 = icmp eq i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 72, i32 0
+  %sel1 = select i1 %cmp1, i32 0, i32 144
+  %out = or disjoint i32 %sel0, %sel1
+  ret i32 %out
+}
+
+define i32 @add_select_cmp_and_pred2(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_and_pred2(
+; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[IN:%.*]], 3
+; CHECK-NEXT:    [[OUT:%.*]] = mul nuw nsw i32 [[TMP1]], 72
+; CHECK-NEXT:    ret i32 [[OUT]]
+;
+  %bitop0 = and i32 %in, 1
+  %cmp0 = icmp eq i32 %bitop0, 0
+  %bitop1 = and i32 %in, 2
+  %cmp1 = icmp ne i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 0, i32 72
+  %sel1 = select i1 %cmp1, i32 144, i32 0
+  %out = or disjoint i32 %sel0, %sel1
+  ret i32 %out
+}
+
+define i32 @add_select_cmp_and_pred3(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_and_pred3(
+; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[IN:%.*]], 3
+; CHECK-NEXT:    [[OUT:%.*]] = mul nuw nsw i32 [[TMP1]], 72
+; CHECK-NEXT:    ret i32 [[OUT]]
+;
+  %bitop0 = and i32 %in, 1
+  %cmp0 = icmp ne i32 %bitop0, 0
+  %bitop1 = and i32 %in, 2
+  %cmp1 = icmp ne i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 72, i32 0
+  %sel1 = select i1 %cmp1, i32 144, i32 0
+  %out = or disjoint i32 %sel0, %sel1
+  ret i32 %out
+}
+
+define i32 @add_select_cmp_trunc(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_trunc(
+; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[IN:%.*]], 3
+; CHECK-NEXT:    [[OUT:%.*]] = mul nuw nsw i32 [[TMP1]], 72
+; CHECK-NEXT:    ret i32 [[OUT]]
+;
+  %cmp0 = trunc i32 %in to i1
+  %bitop1 = and i32 %in, 2
+  %cmp1 = icmp eq i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 72, i32 0
+  %sel1 = select i1 %cmp1, i32 0, i32 144
+  %out = or disjoint i32 %sel0, %sel1
+  ret i32 %out
+}
+
+define i32 @add_select_cmp_trunc1(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_trunc1(
+; CHECK-NEXT:    [[TMP1:%.*]] = and i32 [[IN:%.*]], 3
+; CHECK-NEXT:    [[OUT:%.*]] = mul nuw nsw i32 [[TMP1]], 72
+; CHECK-NEXT:    ret i32 [[OUT]]
+;
+  %cmp0 = trunc i32 %in to i1
+  %bitop1 = and i32 %in, 2
+  %cmp1 = icmp ne i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 72, i32 0
+  %sel1 = select i1 %cmp1, i32 144, i32 0
+  %out = or disjoint i32 %sel0, %sel1
+  ret i32 %out
+}
+
+
+define i32 @add_select_cmp_and_const_mismatch(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_and_const_mismatch(
+; CHECK-NEXT:    [[BITOP0:%.*]] = and i32 [[IN:%.*]], 1
+; CHECK-NEXT:    [[CMP0:%.*]] = icmp eq i32 [[BITOP0]], 0
+; CHECK-NEXT:    [[BITOP1:%.*]] = and i32 [[IN]], 2
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq i32 [[BITOP1]], 0
+; CHECK-NEXT:    [[SEL0:%.*]] = select i1 [[CMP0]], i32 0, i32 72
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[CMP1]], i32 0, i32 288
+; CHECK-NEXT:    [[OUT:%.*]] = or disjoint i32 [[SEL0]], [[SEL1]]
+; CHECK-NEXT:    ret i32 [[OUT]]
+;
+  %bitop0 = and i32 %in, 1
+  %cmp0 = icmp eq i32 %bitop0, 0
+  %bitop1 = and i32 %in, 2
+  %cmp1 = icmp eq i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 0, i32 72
+  %sel1 = select i1 %cmp1, i32 0, i32 288
+  %out = or disjoint i32 %sel0, %sel1
+  ret i32 %out
+}
+
+define i32 @add_select_cmp_and_value_mismatch(i32 %in, i32 %in1) {
+; CHECK-LABEL: @add_select_cmp_and_value_mismatch(
+; CHECK-NEXT:    [[BITOP0:%.*]] = and i32 [[IN:%.*]], 1
+; CHECK-NEXT:    [[CMP0:%.*]] = icmp eq i32 [[BITOP0]], 0
+; CHECK-NEXT:    [[BITOP1:%.*]] = and i32 [[IN1:%.*]], 2
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq i32 [[BITOP1]], 0
+; CHECK-NEXT:    [[SEL0:%.*]] = select i1 [[CMP0]], i32 0, i32 72
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[CMP1]], i32 0, i32 144
+; CHECK-NEXT:    [[OUT:%.*]] = or disjoint i32 [[SEL0]], [[SEL1]]
+; CHECK-NEXT:    ret i32 [[OUT]]
+;
+  %bitop0 = and i32 %in, 1
+  %cmp0 = icmp eq i32 %bitop0, 0
+  %bitop1 = and i32 %in1, 2
+  %cmp1 = icmp eq i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 0, i32 72
+  %sel1 = select i1 %cmp1, i32 0, i32 144
+  %out = or disjoint i32 %sel0, %sel1
+  ret i32 %out
+}
+
+define i32 @add_select_cmp_and_negative(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_and_negative(
+; CHECK-NEXT:    [[BITOP0:%.*]] = and i32 [[IN:%.*]], 1
+; CHECK-NEXT:    [[CMP0:%.*]] = icmp eq i32 [[BITOP0]], 0
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp ult i32 [[IN]], 2
+; CHECK-NEXT:    [[SEL0:%.*]] = select i1 [[CMP0]], i32 0, i32 72
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[CMP1]], i32 0, i32 -144
+; CHECK-NEXT:    [[OUT:%.*]] = or disjoint i32 [[SEL0]], [[SEL1]]
+; CHECK-NEXT:    ret i32 [[OUT]]
+;
+  %bitop0 = and i32 %in, 1
+  %cmp0 = icmp eq i32 %bitop0, 0
+  %bitop1 = and i32 %in, -2
+  %cmp1 = icmp eq i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 0, i32 72
+  %sel1 = select i1 %cmp1, i32 0, i32 -144
+  %out = or disjoint i32 %sel0, %sel1
+  ret i32 %out
+}
+
+define i32 @add_select_cmp_and_bitsel_overlap(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_and_bitsel_overlap(
+; CHECK-NEXT:    [[BITOP0:%.*]] = and i32 [[IN:%.*]], 2
+; CHECK-NEXT:    [[CMP0:%.*]] = icmp eq i32 [[BITOP0]], 0
+; CHECK-NEXT:    [[SEL0:%.*]] = select i1 [[CMP0]], i32 0, i32 144
+; CHECK-NEXT:    ret i32 [[SEL0]]
+;
+  %bitop0 = and i32 %in, 2
+  %cmp0 = icmp eq i32 %bitop0, 0
+  %bitop1 = and i32 %in, 2
+  %cmp1 = icmp eq i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 0, i32 144
+  %sel1 = select i1 %cmp1, i32 0, i32 144
+  %out = or disjoint i32 %sel0, %sel1
+  ret i32 %out
+}
+
+; We cannot combine into and-mul, as %bitop1 may not be exactly 6
+
+define i32 @add_select_cmp_and_multbit_mask(i32 %in) {
+; CHECK-LABEL: @add_select_cmp_and_multbit_mask(
+; CHECK-NEXT:    [[BITOP0:%.*]] = and i32 [[IN:%.*]], 1
+; CHECK-NEXT:    [[CMP0:%.*]] = icmp eq i32 [[BITOP0]], 0
+; CHECK-NEXT:    [[BITOP1:%.*]] = and i32 [[IN]], 6
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq i32 [[BITOP1]], 0
+; CHECK-NEXT:    [[SEL0:%.*]] = select i1 [[CMP0]], i32 0, i32 72
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[CMP1]], i32 0, i32 432
+; CHECK-NEXT:    [[OUT:%.*]] = or disjoint i32 [[SEL0]], [[SEL1]]
+; CHECK-NEXT:    ret i32 [[OUT]]
+;
+  %bitop0 = and i32 %in, 1
+  %cmp0 = icmp eq i32 %bitop0, 0
+  %bitop1 = and i32 %in, 6
+  %cmp1 = icmp eq i32 %bitop1, 0
+  %sel0 = select i1 %cmp0, i32 0, i32 72
+  %sel1 = select i1 %cmp1, i32 0, i32 432
+  %out = or disjoint i32 %sel0, %sel1
+  ret i32 %out
+}
+
+
+define <2 x i32> @add_select_cmp_vec(<2 x i32> %in) {
+; CHECK-LABEL: @add_select_cmp_vec(
+; CHECK-NEXT:    [[TMP1:%.*]] = and <2 x i32> [[IN:%.*]], splat (i32 3)
+; CHECK-NEXT:    [[OUT:%.*]] = mul nuw nsw <2 x i32> [[TMP1]], splat (i32 72)
+; CHECK-NEXT:    ret <2 x i32> [[OUT]]
+;
+  %bitop0 = and <2 x i32> %in, <i32 1, i32 1>
+  %cmp0 = icmp eq <2 x i32> %bitop0, <i32 0, i32 0>
+  %bitop1 = and <2 x i32> %in, <i32 2, i32 2>
+  %cmp1 = icmp eq <2 x i32> %bitop1, <i32 0, i32 0>
+  %sel0 = select <2 x i1> %cmp0, <2 x i32> <i32 0, i32 0>, <2 x i32> <i32 72, i32 72>
+  %sel1 = select <2 x i1> %cmp1, <2 x i32> <i32 0, i32 0>, <2 x i32> <i32 144, i32 144>
+  %out = or disjoint <2 x i32> %sel0, %sel1
+  ret <2 x i32> %out
+}
+
+define <2 x i32> @add_select_cmp_vec_poison(<2 x i32> %in) {
+; CHECK-LABEL: @add_select_cmp_vec_poison(
+; CHECK-NEXT:    [[BITOP0:%.*]] = and <2 x i32> [[IN:%.*]], splat (i32 1)
+; CHECK-NEXT:    [[CMP0:%.*]] = icmp eq <2 x i32> [[BITOP0]], zeroinitializer
+; CHECK-NEXT:    [[BITOP1:%.*]] = and <2 x i32> [[IN]], splat (i32 2)
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq <2 x i32> [[BITOP1]], zeroinitializer
+; CHECK-NEXT:    [[SEL1:%.*]] = select <2 x i1> [[CMP1]], <2 x i32> zeroinitializer, <2 x i32> <i32 poison, i32 144>
+; CHECK-NEXT:    [[OUT:%.*]] = select <2 x i1> [[CMP0]], <2 x i32> [[SEL1]], <2 x i32> <i32 72, i32 poison>
+; CHECK-NEXT:    ret <2 x i32> [[OUT]]
+;
+  %bitop0 = and <2 x i32> %in, <i32 1, i32 1>
+  %cmp0 = icmp eq <2 x i32> %bitop0, <i32 0, i32 0>
+  %bitop1 = and <2 x i32> %in, <i32 2, i32 2>
+  %cmp1 = icmp eq <2 x i32> %bitop1, <i32 0, i32 0>
+  %sel0 = select <2 x i1> %cmp0, <2 x i32> <i32 0, i32 0>, <2 x i32> <i32 72, i32 poison>
+  %sel1 = select <2 x i1> %cmp1, <2 x i32> <i32 0, i32 0>, <2 x i32> <i32 poison, i32 144>
+  %out = or disjoint <2 x i32> %sel0, %sel1
+  ret <2 x i32> %out
+}
+
+define <2 x i32> @add_select_cmp_vec_nonunique(<2 x i32> %in) {
+; CHECK-LABEL: @add_select_cmp_vec_nonunique(
+; CHECK-NEXT:    [[BITOP0:%.*]] = and <2 x i32> [[IN:%.*]], <i32 1, i32 2>
+; CHECK-NEXT:    [[CMP0:%.*]] = icmp eq <2 x i32> [[BITOP0]], zeroinitializer
+; CHECK-NEXT:    [[BITOP1:%.*]] = and <2 x i32> [[IN]], <i32 4, i32 8>
+; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq <2 x i32> [[BITOP1]], zeroinitializer
+; CHECK-NEXT:    [[SEL0:%.*]] = select <2 x i1> [[CMP0]], <2 x i32> zeroinitializer, <2 x i32> <i32 72, i32 144>
+; CHECK-NEXT:    [[SEL1:%.*]] = select <2 x i1> [[CMP1]], <2 x i32> zeroinitializer, <2 x i32> <i32 288, i32 576>
+; CHECK-NEXT:    [[OUT:%.*]] = or disjoint <2 x i32> [[SEL0]], [[SEL1]]
+; CHECK-NEXT:    ret <2 x i32> [[OUT]]
+;
+  %bitop0 = and <2 x i32> %in, <i32 1, i32 2>
+  %cmp0 = icmp eq <2 x i32> %bitop0, <i32 0, i32 0>
+  %bitop1 = and <2 x i32> %in, <i32 4, i32 8>
+  %cmp1 = icmp eq <2 x i32> %bitop1, <i32 0, i32 0>
+  %sel0 = select <2 x i1> %cmp0, <2 x i32> <i32 0, i32 0>, <2 x i32> <i32 72, i32 144>
+  %sel1 = select <2 x i1> %cmp1, <2 x i32> <i32 0, i32 0>, <2 x i32> <i32 288, i32 576>
+  %out = or disjoint <2 x i32> %sel0, %sel1
+  ret <2 x i32> %out
+}
+;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+; CONSTSPLAT: {{.*}}
+; CONSTVEC: {{.*}}
\ No newline at end of file

>From 691d72d75308b52812eb4639cfecb91deb0dace3 Mon Sep 17 00:00:00 2001
From: Jeffrey Byrnes <jeffrey.byrnes at amd.com>
Date: Fri, 25 Apr 2025 08:32:46 -0700
Subject: [PATCH 2/3] Update llvm/test/Transforms/InstCombine/or-bitmask.ll

Co-authored-by: Matt Arsenault <arsenm2 at gmail.com>
---
 llvm/test/Transforms/InstCombine/or-bitmask.ll | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/llvm/test/Transforms/InstCombine/or-bitmask.ll b/llvm/test/Transforms/InstCombine/or-bitmask.ll
index 18acc42f2dc40..2c020fd9456e1 100644
--- a/llvm/test/Transforms/InstCombine/or-bitmask.ll
+++ b/llvm/test/Transforms/InstCombine/or-bitmask.ll
@@ -325,4 +325,4 @@ define <2 x i32> @add_select_cmp_vec_nonunique(<2 x i32> %in) {
 }
 ;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
 ; CONSTSPLAT: {{.*}}
-; CONSTVEC: {{.*}}
\ No newline at end of file
+; CONSTVEC: {{.*}}

>From 178168ecae7674a9eff072bf9c3ae3d2490f60ef Mon Sep 17 00:00:00 2001
From: Jeffrey Byrnes <jeffrey.byrnes at amd.com>
Date: Fri, 2 May 2025 15:01:13 -0700
Subject: [PATCH 3/3] Apply suggestions from code review

Co-authored-by: Yingwei Zheng <dtcxzyw at qq.com>
---
 llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
index 18d3f551adef4..e8eb542194eda 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
@@ -3662,17 +3662,15 @@ Instruction *InstCombinerImpl::visitOr(BinaryOperator &I) {
 
       if (LHSDecompose && RHSDecompose && LHSDecompose->X == RHSDecompose->X &&
           (ICmpInst::isEquality(LHSDecompose->Pred)) &&
-          !RHSDecompose->Mask.isNegative() &&
-          !LHSDecompose->Mask.isNegative() && RHSDecompose->Mask.isPowerOf2() &&
+         RHSDecompose->Mask.isPowerOf2() &&
           LHSDecompose->Mask.isPowerOf2() &&
-          LHSDecompose->Mask != RHSDecompose->Mask &&
-          LHSDecompose->C.isZero() && RHSDecompose->C.isZero()) {
+          LHSDecompose->Mask != RHSDecompose->Mask) {
         if (LHSDecompose->Pred == ICmpInst::ICMP_NE)
           std::swap(Op0Eq, Op0Ne);
         if (RHSDecompose->Pred == ICmpInst::ICMP_NE)
           std::swap(Op1Eq, Op1Ne);
 
-        if (Op0Ne->isStrictlyPositive() && Op1Ne->isStrictlyPositive() &&
+        if (!Op0Ne->isZero() && !Op1Ne->isZero() &&
             Op0Eq->isZero() && Op1Eq->isZero() &&
             Op0Ne->urem(LHSDecompose->Mask).isZero() &&
             Op1Ne->urem(RHSDecompose->Mask).isZero() &&



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