[llvm] [InstCombine] Fold select of intrinsic into intrinsic of select (PR #178002)

Gauravsingh Sisodia via llvm-commits llvm-commits at lists.llvm.org
Mon Jan 26 09:36:55 PST 2026


https://github.com/xaerru created https://github.com/llvm/llvm-project/pull/178002

Fix https://github.com/llvm/llvm-project/issues/140917

Transform:
`select cond, intrinsic(x, ...), intrinsic(y, ...)`
into:
`intrinsic(select cond, x, y, ...)`
for `ctpop/ctlz/cttz/abs`.

alive2 proof: https://alive2.llvm.org/ce/z/Zp55Dy

>From 7ab398f3e6a37243f1fb4b621507d7aac7f6ac1a Mon Sep 17 00:00:00 2001
From: Gauravsingh Sisodia <xaerru at gmail.com>
Date: Mon, 26 Jan 2026 16:55:39 +0000
Subject: [PATCH 1/2] [InstCombine] Add tests for folding select of intrinsic

---
 .../InstCombine/intrinsic-select.ll           | 146 ++++++++++++++++++
 1 file changed, 146 insertions(+)

diff --git a/llvm/test/Transforms/InstCombine/intrinsic-select.ll b/llvm/test/Transforms/InstCombine/intrinsic-select.ll
index c8f5a216ed534..99cc8b675c1a2 100644
--- a/llvm/test/Transforms/InstCombine/intrinsic-select.ll
+++ b/llvm/test/Transforms/InstCombine/intrinsic-select.ll
@@ -532,3 +532,149 @@ define <2 x i8> @test_select_rotate_right_non_splat(i1 %0) {
   %ret = call <2 x i8> @llvm.fshr.v2i8(<2 x i8> %s, <2 x i8> %s, <2 x i8> <i8 7, i8 7>)
   ret <2 x i8> %ret
 }
+
+define i32 @select_of_ctpop(i1 %cond, i32 %x, i32 %y) {
+; CHECK-LABEL: @select_of_ctpop(
+; CHECK-NEXT:    [[SEL:%.*]] = call range(i32 0, 33) i32 @llvm.ctpop.i32(i32 [[TMP1:%.*]])
+; CHECK-NEXT:    [[CTPOP2:%.*]] = call range(i32 0, 33) i32 @llvm.ctpop.i32(i32 [[Y:%.*]])
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[SEL]], i32 [[CTPOP2]]
+; CHECK-NEXT:    ret i32 [[SEL1]]
+;
+  %ctpop1 = call i32 @llvm.ctpop.i32(i32 %x)
+  %ctpop2 = call i32 @llvm.ctpop.i32(i32 %y)
+  %sel = select i1 %cond, i32 %ctpop1, i32 %ctpop2
+  ret i32 %sel
+}
+
+; Negative test: TV is not ctpop, should not transform
+define i32 @select_of_ctpop_negative_tv(i1 %cond, i32 %x, i32 %y) {
+; CHECK-LABEL: @select_of_ctpop_negative_tv(
+; CHECK-NEXT:    [[CTPOP2:%.*]] = call range(i32 0, 33) i32 @llvm.ctpop.i32(i32 [[Y:%.*]])
+; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[COND:%.*]], i32 [[X:%.*]], i32 [[CTPOP2]]
+; CHECK-NEXT:    ret i32 [[SEL]]
+;
+  %ctpop1 = add i32 %x, 0
+  %ctpop2 = call i32 @llvm.ctpop.i32(i32 %y)
+  %sel = select i1 %cond, i32 %ctpop1, i32 %ctpop2
+  ret i32 %sel
+}
+
+; Negative test: FV is not ctpop, should not transform
+define i32 @select_of_ctpop_negative_fv(i1 %cond, i32 %x, i32 %y) {
+; CHECK-LABEL: @select_of_ctpop_negative_fv(
+; CHECK-NEXT:    [[CTPOP1:%.*]] = call range(i32 0, 33) i32 @llvm.ctpop.i32(i32 [[Y:%.*]])
+; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[COND:%.*]], i32 [[CTPOP1]], i32 [[X:%.*]]
+; CHECK-NEXT:    ret i32 [[SEL]]
+;
+  %ctpop1 = call i32 @llvm.ctpop.i32(i32 %y)
+  %ctpop2 = add i32 %x, 0
+  %sel = select i1 %cond, i32 %ctpop1, i32 %ctpop2
+  ret i32 %sel
+}
+
+define i32 @select_of_ctpop_multi_use(i1 %cond, i32 %x, i32 %y) {
+; CHECK-LABEL: @select_of_ctpop_multi_use(
+; CHECK-NEXT:    [[CTPOP1:%.*]] = call range(i32 0, 33) i32 @llvm.ctpop.i32(i32 [[X:%.*]])
+; CHECK-NEXT:    call void @use(i32 [[CTPOP1]])
+; CHECK-NEXT:    [[SEL:%.*]] = call range(i32 0, 33) i32 @llvm.ctpop.i32(i32 [[TMP1:%.*]])
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[CTPOP1]], i32 [[SEL]]
+; CHECK-NEXT:    ret i32 [[SEL1]]
+;
+  %ctpop1 = call i32 @llvm.ctpop.i32(i32 %x)
+  call void @use(i32 %ctpop1)
+  %ctpop2 = call i32 @llvm.ctpop.i32(i32 %y)
+  %sel = select i1 %cond, i32 %ctpop1, i32 %ctpop2
+  ret i32 %sel
+}
+
+define <4 x i32> @select_of_ctpop_vec(<4 x i1> %cond, <4 x i32> %x, <4 x i32> %y) {
+; CHECK-LABEL: @select_of_ctpop_vec(
+; CHECK-NEXT:    [[SEL:%.*]] = call range(i32 0, 33) <4 x i32> @llvm.ctpop.v4i32(<4 x i32> [[TMP1:%.*]])
+; CHECK-NEXT:    [[CTPOP2:%.*]] = call range(i32 0, 33) <4 x i32> @llvm.ctpop.v4i32(<4 x i32> [[Y:%.*]])
+; CHECK-NEXT:    [[SEL1:%.*]] = select <4 x i1> [[COND:%.*]], <4 x i32> [[SEL]], <4 x i32> [[CTPOP2]]
+; CHECK-NEXT:    ret <4 x i32> [[SEL1]]
+;
+  %ctpop1 = call <4 x i32> @llvm.ctpop.v4i32(<4 x i32> %x)
+  %ctpop2 = call <4 x i32> @llvm.ctpop.v4i32(<4 x i32> %y)
+  %sel = select <4 x i1> %cond, <4 x i32> %ctpop1, <4 x i32> %ctpop2
+  ret <4 x i32> %sel
+}
+
+define i32 @select_of_ctlz(i1 %cond, i32 %x, i32 %y) {
+; CHECK-LABEL: @select_of_ctlz(
+; CHECK-NEXT:    [[SEL:%.*]] = call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 [[TMP1:%.*]], i1 false)
+; CHECK-NEXT:    [[CTLZ2:%.*]] = call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 [[Y:%.*]], i1 false)
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[SEL]], i32 [[CTLZ2]]
+; CHECK-NEXT:    ret i32 [[SEL1]]
+;
+  %ctlz1 = call i32 @llvm.ctlz.i32(i32 %x, i1 false)
+  %ctlz2 = call i32 @llvm.ctlz.i32(i32 %y, i1 false)
+  %sel = select i1 %cond, i32 %ctlz1, i32 %ctlz2
+  ret i32 %sel
+}
+
+; Negative test: zero poison flags differ, don't transform
+define i32 @select_of_ctlz_negative_zero_poison(i1 %cond, i32 %x, i32 %y) {
+; CHECK-LABEL: @select_of_ctlz_negative_zero_poison(
+; CHECK-NEXT:    [[CTLZ1:%.*]] = call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 [[X:%.*]], i1 false)
+; CHECK-NEXT:    [[CTLZ2:%.*]] = call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 [[Y:%.*]], i1 true)
+; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[COND:%.*]], i32 [[CTLZ1]], i32 [[CTLZ2]]
+; CHECK-NEXT:    ret i32 [[SEL]]
+;
+  %ctlz1 = call i32 @llvm.ctlz.i32(i32 %x, i1 false)
+  %ctlz2 = call i32 @llvm.ctlz.i32(i32 %y, i1 true)
+  %sel = select i1 %cond, i32 %ctlz1, i32 %ctlz2
+  ret i32 %sel
+}
+
+define i32 @select_of_ctlz_multi_use(i1 %cond, i32 %x, i32 %y) {
+; CHECK-LABEL: @select_of_ctlz_multi_use(
+; CHECK-NEXT:    [[CTLZ1:%.*]] = call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 [[X:%.*]], i1 false)
+; CHECK-NEXT:    call void @use(i32 [[CTLZ1]])
+; CHECK-NEXT:    [[SEL:%.*]] = call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 [[TMP1:%.*]], i1 false)
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[CTLZ1]], i32 [[SEL]]
+; CHECK-NEXT:    ret i32 [[SEL1]]
+;
+  %ctlz1 = call i32 @llvm.ctlz.i32(i32 %x, i1 false)
+  call void @use(i32 %ctlz1)
+  %ctlz2 = call i32 @llvm.ctlz.i32(i32 %y, i1 false)
+  %sel = select i1 %cond, i32 %ctlz1, i32 %ctlz2
+  ret i32 %sel
+}
+
+define <4 x i32> @select_of_ctlz_vec(<4 x i1> %cond, <4 x i32> %x, <4 x i32> %y) {
+; CHECK-LABEL: @select_of_ctlz_vec(
+; CHECK-NEXT:    [[CTLZ2:%.*]] = call range(i32 0, 33) <4 x i32> @llvm.ctlz.v4i32(<4 x i32> [[Y:%.*]], i1 false)
+; CHECK-NEXT:    ret <4 x i32> [[CTLZ2]]
+;
+  %ctlz1 = call <4 x i32> @llvm.ctlz.v4i32(<4 x i32> %x, i1 false)
+  %ctlz2 = call <4 x i32> @llvm.ctlz.v4i32(<4 x i32> %y, i1 false)
+  %sel = select <4 x i1> %cond, <4 x i32> %ctlz2, <4 x i32> %ctlz2
+  ret <4 x i32> %sel
+}
+
+define i32 @select_of_cttz(i1 %cond, i32 %x, i32 %y) {
+; CHECK-LABEL: @select_of_cttz(
+; CHECK-NEXT:    [[SEL:%.*]] = call range(i32 0, 33) i32 @llvm.cttz.i32(i32 [[TMP1:%.*]], i1 false)
+; CHECK-NEXT:    [[CTTZ2:%.*]] = call range(i32 0, 33) i32 @llvm.cttz.i32(i32 [[Y:%.*]], i1 false)
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[SEL]], i32 [[CTTZ2]]
+; CHECK-NEXT:    ret i32 [[SEL1]]
+;
+  %cttz1 = call i32 @llvm.cttz.i32(i32 %x, i1 false)
+  %cttz2 = call i32 @llvm.cttz.i32(i32 %y, i1 false)
+  %sel = select i1 %cond, i32 %cttz1, i32 %cttz2
+  ret i32 %sel
+}
+
+define i32 @select_of_abs(i1 %cond, i32 %x, i32 %y) {
+; CHECK-LABEL: @select_of_abs(
+; CHECK-NEXT:    [[SEL:%.*]] = call i32 @llvm.abs.i32(i32 [[TMP1:%.*]], i1 false)
+; CHECK-NEXT:    [[ABS2:%.*]] = call i32 @llvm.abs.i32(i32 [[Y:%.*]], i1 false)
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[SEL]], i32 [[ABS2]]
+; CHECK-NEXT:    ret i32 [[SEL1]]
+;
+  %abs1 = call i32 @llvm.abs.i32(i32 %x, i1 false)
+  %abs2 = call i32 @llvm.abs.i32(i32 %y, i1 false)
+  %sel = select i1 %cond, i32 %abs1, i32 %abs2
+  ret i32 %sel
+}

>From 082937618257773112f922b617e2b606461ab03c Mon Sep 17 00:00:00 2001
From: Gauravsingh Sisodia <xaerru at gmail.com>
Date: Mon, 26 Jan 2026 16:59:34 +0000
Subject: [PATCH 2/2] [InstCombine] Fold select of intrinsic into intrinsic of
 select

---
 .../InstCombine/InstCombineInternal.h         |  1 +
 .../InstCombine/InstCombineSelect.cpp         | 61 +++++++++++++++++++
 .../InstCombine/intrinsic-select.ll           | 43 ++++++-------
 3 files changed, 81 insertions(+), 24 deletions(-)

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineInternal.h b/llvm/lib/Transforms/InstCombine/InstCombineInternal.h
index 8c8b300bb2002..8a478bf344536 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineInternal.h
+++ b/llvm/lib/Transforms/InstCombine/InstCombineInternal.h
@@ -805,6 +805,7 @@ class LLVM_LIBRARY_VISIBILITY InstCombinerImpl final
   Instruction *foldSelectExtConst(SelectInst &Sel);
   Instruction *foldSelectEqualityTest(SelectInst &SI);
   Instruction *foldSelectOpOp(SelectInst &SI, Instruction *TI, Instruction *FI);
+  Instruction *foldSelectIntrinsic(SelectInst &SI);
   Instruction *foldSelectIntoOp(SelectInst &SI, Value *, Value *);
   Instruction *foldSPFofSPF(Instruction *Inner, SelectPatternFlavor SPF1,
                             Value *A, Value *B, Instruction &Outer,
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
index 00f4118d538d8..3921a8f3ba8d4 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
@@ -492,6 +492,64 @@ Instruction *InstCombinerImpl::foldSelectOpOp(SelectInst &SI, Instruction *TI,
   return nullptr;
 }
 
+template <Intrinsic::ID ID>
+static Instruction *foldSelectIntrinsicUnary(SelectInst &SI,
+                                             InstCombiner::BuilderTy &Builder) {
+  Value *TrueV = SI.getTrueValue();
+  Value *FalseV = SI.getFalseValue();
+  Value *TV = nullptr, *FV = nullptr;
+
+  if (match(TrueV, m_Intrinsic<ID>(m_Value(TV))) &&
+      match(FalseV, m_Intrinsic<ID>(m_Value(FV)))) {
+    Value *NewSel = Builder.CreateSelect(SI.getCondition(), TV, FV);
+    Instruction *NewCall =
+        Builder.CreateIntrinsic(ID, {NewSel->getType()}, {NewSel});
+    return NewCall;
+  }
+  return nullptr;
+}
+
+template <Intrinsic::ID ID>
+static Instruction *
+foldSelectIntrinsicBinary(SelectInst &SI, InstCombiner::BuilderTy &Builder) {
+  Value *TrueV = SI.getTrueValue();
+  Value *FalseV = SI.getFalseValue();
+  Value *TV = nullptr, *FV = nullptr;
+  ConstantInt *TZ = nullptr, *FZ = nullptr;
+
+  if (match(TrueV, m_Intrinsic<ID>(m_Value(TV), m_ConstantInt(TZ))) &&
+      match(FalseV, m_Intrinsic<ID>(m_Value(FV), m_ConstantInt(FZ))) &&
+      TZ == FZ) {
+    Value *NewSel = Builder.CreateSelect(SI.getCondition(), TV, FV);
+    Instruction *NewCall =
+        Builder.CreateIntrinsic(ID, {NewSel->getType()}, {NewSel, TZ});
+    return NewCall;
+  }
+  return nullptr;
+}
+
+/// This transforms patterns of the form:
+///   select cond, intrinsic(x, ...), intrinsic(y, ...)
+/// into:
+///   intrinsic(select cond, x, y, ...)
+Instruction *InstCombinerImpl::foldSelectIntrinsic(SelectInst &SI) {
+  Instruction *ResCall = nullptr;
+
+  if ((ResCall = foldSelectIntrinsicUnary<Intrinsic::ctpop>(SI, Builder))) {
+    return replaceInstUsesWith(SI, ResCall);
+  }
+  if ((ResCall = foldSelectIntrinsicBinary<Intrinsic::ctlz>(SI, Builder))) {
+    return replaceInstUsesWith(SI, ResCall);
+  }
+  if ((ResCall = foldSelectIntrinsicBinary<Intrinsic::cttz>(SI, Builder))) {
+    return replaceInstUsesWith(SI, ResCall);
+  }
+  if ((ResCall = foldSelectIntrinsicBinary<Intrinsic::abs>(SI, Builder))) {
+    return replaceInstUsesWith(SI, ResCall);
+  }
+  return nullptr;
+}
+
 static bool isSelect01(const APInt &C1I, const APInt &C2I) {
   if (!C1I.isZero() && !C2I.isZero()) // One side must be zero.
     return false;
@@ -4440,6 +4498,9 @@ Instruction *InstCombinerImpl::visitSelectInst(SelectInst &SI) {
     if (Instruction *IV = foldSelectOpOp(SI, TI, FI))
       return IV;
 
+  if (Instruction *I = foldSelectIntrinsic(SI))
+    return I;
+
   if (Instruction *I = foldSelectExtConst(SI))
     return I;
 
diff --git a/llvm/test/Transforms/InstCombine/intrinsic-select.ll b/llvm/test/Transforms/InstCombine/intrinsic-select.ll
index 99cc8b675c1a2..4bf5f1100f13f 100644
--- a/llvm/test/Transforms/InstCombine/intrinsic-select.ll
+++ b/llvm/test/Transforms/InstCombine/intrinsic-select.ll
@@ -535,10 +535,9 @@ define <2 x i8> @test_select_rotate_right_non_splat(i1 %0) {
 
 define i32 @select_of_ctpop(i1 %cond, i32 %x, i32 %y) {
 ; CHECK-LABEL: @select_of_ctpop(
-; CHECK-NEXT:    [[SEL:%.*]] = call range(i32 0, 33) i32 @llvm.ctpop.i32(i32 [[TMP1:%.*]])
-; CHECK-NEXT:    [[CTPOP2:%.*]] = call range(i32 0, 33) i32 @llvm.ctpop.i32(i32 [[Y:%.*]])
-; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[SEL]], i32 [[CTPOP2]]
-; CHECK-NEXT:    ret i32 [[SEL1]]
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[SEL:%.*]], i32 [[CTPOP2:%.*]]
+; CHECK-NEXT:    [[SEL2:%.*]] = call range(i32 0, 33) i32 @llvm.ctpop.i32(i32 [[SEL1]])
+; CHECK-NEXT:    ret i32 [[SEL2]]
 ;
   %ctpop1 = call i32 @llvm.ctpop.i32(i32 %x)
   %ctpop2 = call i32 @llvm.ctpop.i32(i32 %y)
@@ -576,8 +575,8 @@ define i32 @select_of_ctpop_multi_use(i1 %cond, i32 %x, i32 %y) {
 ; CHECK-LABEL: @select_of_ctpop_multi_use(
 ; CHECK-NEXT:    [[CTPOP1:%.*]] = call range(i32 0, 33) i32 @llvm.ctpop.i32(i32 [[X:%.*]])
 ; CHECK-NEXT:    call void @use(i32 [[CTPOP1]])
-; CHECK-NEXT:    [[SEL:%.*]] = call range(i32 0, 33) i32 @llvm.ctpop.i32(i32 [[TMP1:%.*]])
-; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[CTPOP1]], i32 [[SEL]]
+; CHECK-NEXT:    [[TMP1:%.*]] = select i1 [[COND:%.*]], i32 [[X]], i32 [[Y:%.*]]
+; CHECK-NEXT:    [[SEL1:%.*]] = call range(i32 0, 33) i32 @llvm.ctpop.i32(i32 [[TMP1]])
 ; CHECK-NEXT:    ret i32 [[SEL1]]
 ;
   %ctpop1 = call i32 @llvm.ctpop.i32(i32 %x)
@@ -589,10 +588,9 @@ define i32 @select_of_ctpop_multi_use(i1 %cond, i32 %x, i32 %y) {
 
 define <4 x i32> @select_of_ctpop_vec(<4 x i1> %cond, <4 x i32> %x, <4 x i32> %y) {
 ; CHECK-LABEL: @select_of_ctpop_vec(
-; CHECK-NEXT:    [[SEL:%.*]] = call range(i32 0, 33) <4 x i32> @llvm.ctpop.v4i32(<4 x i32> [[TMP1:%.*]])
-; CHECK-NEXT:    [[CTPOP2:%.*]] = call range(i32 0, 33) <4 x i32> @llvm.ctpop.v4i32(<4 x i32> [[Y:%.*]])
-; CHECK-NEXT:    [[SEL1:%.*]] = select <4 x i1> [[COND:%.*]], <4 x i32> [[SEL]], <4 x i32> [[CTPOP2]]
-; CHECK-NEXT:    ret <4 x i32> [[SEL1]]
+; CHECK-NEXT:    [[SEL1:%.*]] = select <4 x i1> [[COND:%.*]], <4 x i32> [[SEL:%.*]], <4 x i32> [[CTPOP2:%.*]]
+; CHECK-NEXT:    [[SEL2:%.*]] = call range(i32 0, 33) <4 x i32> @llvm.ctpop.v4i32(<4 x i32> [[SEL1]])
+; CHECK-NEXT:    ret <4 x i32> [[SEL2]]
 ;
   %ctpop1 = call <4 x i32> @llvm.ctpop.v4i32(<4 x i32> %x)
   %ctpop2 = call <4 x i32> @llvm.ctpop.v4i32(<4 x i32> %y)
@@ -602,10 +600,9 @@ define <4 x i32> @select_of_ctpop_vec(<4 x i1> %cond, <4 x i32> %x, <4 x i32> %y
 
 define i32 @select_of_ctlz(i1 %cond, i32 %x, i32 %y) {
 ; CHECK-LABEL: @select_of_ctlz(
-; CHECK-NEXT:    [[SEL:%.*]] = call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 [[TMP1:%.*]], i1 false)
-; CHECK-NEXT:    [[CTLZ2:%.*]] = call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 [[Y:%.*]], i1 false)
-; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[SEL]], i32 [[CTLZ2]]
-; CHECK-NEXT:    ret i32 [[SEL1]]
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[SEL:%.*]], i32 [[CTLZ2:%.*]]
+; CHECK-NEXT:    [[SEL2:%.*]] = call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 [[SEL1]], i1 false)
+; CHECK-NEXT:    ret i32 [[SEL2]]
 ;
   %ctlz1 = call i32 @llvm.ctlz.i32(i32 %x, i1 false)
   %ctlz2 = call i32 @llvm.ctlz.i32(i32 %y, i1 false)
@@ -631,8 +628,8 @@ define i32 @select_of_ctlz_multi_use(i1 %cond, i32 %x, i32 %y) {
 ; CHECK-LABEL: @select_of_ctlz_multi_use(
 ; CHECK-NEXT:    [[CTLZ1:%.*]] = call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 [[X:%.*]], i1 false)
 ; CHECK-NEXT:    call void @use(i32 [[CTLZ1]])
-; CHECK-NEXT:    [[SEL:%.*]] = call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 [[TMP1:%.*]], i1 false)
-; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[CTLZ1]], i32 [[SEL]]
+; CHECK-NEXT:    [[TMP1:%.*]] = select i1 [[COND:%.*]], i32 [[X]], i32 [[Y:%.*]]
+; CHECK-NEXT:    [[SEL1:%.*]] = call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 [[TMP1]], i1 false)
 ; CHECK-NEXT:    ret i32 [[SEL1]]
 ;
   %ctlz1 = call i32 @llvm.ctlz.i32(i32 %x, i1 false)
@@ -655,10 +652,9 @@ define <4 x i32> @select_of_ctlz_vec(<4 x i1> %cond, <4 x i32> %x, <4 x i32> %y)
 
 define i32 @select_of_cttz(i1 %cond, i32 %x, i32 %y) {
 ; CHECK-LABEL: @select_of_cttz(
-; CHECK-NEXT:    [[SEL:%.*]] = call range(i32 0, 33) i32 @llvm.cttz.i32(i32 [[TMP1:%.*]], i1 false)
-; CHECK-NEXT:    [[CTTZ2:%.*]] = call range(i32 0, 33) i32 @llvm.cttz.i32(i32 [[Y:%.*]], i1 false)
-; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[SEL]], i32 [[CTTZ2]]
-; CHECK-NEXT:    ret i32 [[SEL1]]
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[SEL:%.*]], i32 [[CTTZ2:%.*]]
+; CHECK-NEXT:    [[SEL2:%.*]] = call range(i32 0, 33) i32 @llvm.cttz.i32(i32 [[SEL1]], i1 false)
+; CHECK-NEXT:    ret i32 [[SEL2]]
 ;
   %cttz1 = call i32 @llvm.cttz.i32(i32 %x, i1 false)
   %cttz2 = call i32 @llvm.cttz.i32(i32 %y, i1 false)
@@ -668,10 +664,9 @@ define i32 @select_of_cttz(i1 %cond, i32 %x, i32 %y) {
 
 define i32 @select_of_abs(i1 %cond, i32 %x, i32 %y) {
 ; CHECK-LABEL: @select_of_abs(
-; CHECK-NEXT:    [[SEL:%.*]] = call i32 @llvm.abs.i32(i32 [[TMP1:%.*]], i1 false)
-; CHECK-NEXT:    [[ABS2:%.*]] = call i32 @llvm.abs.i32(i32 [[Y:%.*]], i1 false)
-; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[SEL]], i32 [[ABS2]]
-; CHECK-NEXT:    ret i32 [[SEL1]]
+; CHECK-NEXT:    [[SEL1:%.*]] = select i1 [[COND:%.*]], i32 [[SEL:%.*]], i32 [[ABS2:%.*]]
+; CHECK-NEXT:    [[SEL2:%.*]] = call i32 @llvm.abs.i32(i32 [[SEL1]], i1 false)
+; CHECK-NEXT:    ret i32 [[SEL2]]
 ;
   %abs1 = call i32 @llvm.abs.i32(i32 %x, i1 false)
   %abs2 = call i32 @llvm.abs.i32(i32 %y, i1 false)



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