Revert "[InstCombine] Allow freezing multiple operands (#154336)"#182769
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@llvm/pr-subscribers-llvm-transforms @llvm/pr-subscribers-pgo Author: Eli Friedman (efriedma-quic) ChangesThis reverts commit f8f6965. This is causing infinte loops interacting with other transforms. See discussion on #182647 . Patch is 30.77 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/182769.diff 13 Files Affected:
diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index fd699381c22fa..1208f5d1e41b9 100644
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -5199,68 +5199,63 @@ Instruction *InstCombinerImpl::visitLandingPadInst(LandingPadInst &LI) {
Value *
InstCombinerImpl::pushFreezeToPreventPoisonFromPropagating(FreezeInst &OrigFI) {
// Try to push freeze through instructions that propagate but don't produce
- // poison as far as possible. If an operand of freeze does not produce poison
- // then push the freeze through to the operands that are not guaranteed
- // non-poison. The actual transform is as follows.
- // Op1 = ... ; Op1 can be poison
- // Op0 = Inst(Op1, NonPoisonOps...)
+ // poison as far as possible. If an operand of freeze follows three
+ // conditions 1) one-use, 2) does not produce poison, and 3) has all but one
+ // guaranteed-non-poison operands then push the freeze through to the one
+ // operand that is not guaranteed non-poison. The actual transform is as
+ // follows.
+ // Op1 = ... ; Op1 can be posion
+ // Op0 = Inst(Op1, NonPoisonOps...) ; Op0 has only one use and only have
+ // ; single guaranteed-non-poison operands
// ... = Freeze(Op0)
// =>
// Op1 = ...
// Op1.fr = Freeze(Op1)
// ... = Inst(Op1.fr, NonPoisonOps...)
+ auto *OrigOp = OrigFI.getOperand(0);
+ auto *OrigOpInst = dyn_cast<Instruction>(OrigOp);
- auto CanPushFreeze = [](Value *V) {
- if (!isa<Instruction>(V) || isa<PHINode>(V))
- return false;
-
- // We can't push the freeze through an instruction which can itself create
- // poison. If the only source of new poison is flags, we can simply
- // strip them (since we know the only use is the freeze and nothing can
- // benefit from them.)
- return !canCreateUndefOrPoison(cast<Operator>(V),
- /*ConsiderFlagsAndMetadata*/ false);
- };
+ // While we could change the other users of OrigOp to use freeze(OrigOp), that
+ // potentially reduces their optimization potential, so let's only do this iff
+ // the OrigOp is only used by the freeze.
+ if (!OrigOpInst || !OrigOpInst->hasOneUse() || isa<PHINode>(OrigOp))
+ return nullptr;
- // Pushing freezes up long instruction chains can be expensive. Instead,
- // we directly push the freeze all the way to the leaves. However, we leave
- // deduplication of freezes on the same value for freezeOtherUses().
- Use *OrigUse = &OrigFI.getOperandUse(0);
- SmallPtrSet<Instruction *, 8> Visited;
- SmallVector<Use *, 8> Worklist;
- Worklist.push_back(OrigUse);
- while (!Worklist.empty()) {
- auto *U = Worklist.pop_back_val();
- Value *V = U->get();
- if (!CanPushFreeze(V)) {
- // If we can't push through the original instruction, abort the transform.
- if (U == OrigUse)
- return nullptr;
+ // We can't push the freeze through an instruction which can itself create
+ // poison. If the only source of new poison is flags, we can simply
+ // strip them (since we know the only use is the freeze and nothing can
+ // benefit from them.)
+ if (canCreateUndefOrPoison(cast<Operator>(OrigOp),
+ /*ConsiderFlagsAndMetadata*/ false))
+ return nullptr;
- auto *UserI = cast<Instruction>(U->getUser());
- Builder.SetInsertPoint(UserI);
- Value *Frozen = Builder.CreateFreeze(V, V->getName() + ".fr");
- U->set(Frozen);
+ // If operand is guaranteed not to be poison, there is no need to add freeze
+ // to the operand. So we first find the operand that is not guaranteed to be
+ // poison.
+ Value *MaybePoisonOperand = nullptr;
+ for (Value *V : OrigOpInst->operands()) {
+ if (isa<MetadataAsValue>(V) || isGuaranteedNotToBeUndefOrPoison(V) ||
+ // Treat identical operands as a single operand.
+ (MaybePoisonOperand && MaybePoisonOperand == V))
continue;
- }
+ if (!MaybePoisonOperand)
+ MaybePoisonOperand = V;
+ else
+ return nullptr;
+ }
- auto *I = cast<Instruction>(V);
- if (!Visited.insert(I).second)
- continue;
+ OrigOpInst->dropPoisonGeneratingAnnotations();
- // reverse() to emit freezes in a more natural order.
- for (Use &Op : reverse(I->operands())) {
- Value *OpV = Op.get();
- if (isa<MetadataAsValue>(OpV) || isGuaranteedNotToBeUndefOrPoison(OpV))
- continue;
- Worklist.push_back(&Op);
- }
+ // If all operands are guaranteed to be non-poison, we can drop freeze.
+ if (!MaybePoisonOperand)
+ return OrigOp;
- I->dropPoisonGeneratingAnnotations();
- this->Worklist.add(I);
- }
+ Builder.SetInsertPoint(OrigOpInst);
+ Value *FrozenMaybePoisonOperand = Builder.CreateFreeze(
+ MaybePoisonOperand, MaybePoisonOperand->getName() + ".fr");
- return OrigUse->get();
+ OrigOpInst->replaceUsesOfWith(MaybePoisonOperand, FrozenMaybePoisonOperand);
+ return OrigOp;
}
Instruction *InstCombinerImpl::foldFreezeIntoRecurrence(FreezeInst &FI,
diff --git a/llvm/test/Transforms/InstCombine/freeze-fp-ops.ll b/llvm/test/Transforms/InstCombine/freeze-fp-ops.ll
index b1c6fc05e864c..1caf7ec87016e 100644
--- a/llvm/test/Transforms/InstCombine/freeze-fp-ops.ll
+++ b/llvm/test/Transforms/InstCombine/freeze-fp-ops.ll
@@ -163,9 +163,8 @@ define float @freeze_sqrt(float %arg) {
define float @freeze_powi(float %arg0, i32 %arg1) {
; CHECK-LABEL: define float @freeze_powi(
; CHECK-SAME: float [[ARG0:%.*]], i32 [[ARG1:%.*]]) {
-; CHECK-NEXT: [[ARG0_FR:%.*]] = freeze float [[ARG0]]
-; CHECK-NEXT: [[ARG1_FR:%.*]] = freeze i32 [[ARG1]]
-; CHECK-NEXT: [[OP:%.*]] = call float @llvm.powi.f32.i32(float [[ARG0_FR]], i32 [[ARG1_FR]])
+; CHECK-NEXT: [[OP1:%.*]] = call float @llvm.powi.f32.i32(float [[ARG0]], i32 [[ARG1]])
+; CHECK-NEXT: [[OP:%.*]] = freeze float [[OP1]]
; CHECK-NEXT: ret float [[OP]]
;
%op = call float @llvm.powi.f32.i32(float %arg0, i32 %arg1)
diff --git a/llvm/test/Transforms/InstCombine/freeze.ll b/llvm/test/Transforms/InstCombine/freeze.ll
index 6ff13c005a999..80db307ff5e25 100644
--- a/llvm/test/Transforms/InstCombine/freeze.ll
+++ b/llvm/test/Transforms/InstCombine/freeze.ll
@@ -108,9 +108,8 @@ define <3 x i4> @partial_undef_vec() {
define i32 @early_freeze_test1(i32 %x, i32 %y) {
; CHECK-LABEL: define i32 @early_freeze_test1(
; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
-; CHECK-NEXT: [[X_FR:%.*]] = freeze i32 [[X]]
-; CHECK-NEXT: [[Y_FR:%.*]] = freeze i32 [[Y]]
-; CHECK-NEXT: [[V1:%.*]] = add i32 [[X_FR]], [[Y_FR]]
+; CHECK-NEXT: [[V4:%.*]] = add i32 [[X]], [[Y]]
+; CHECK-NEXT: [[V1:%.*]] = freeze i32 [[V4]]
; CHECK-NEXT: [[V2:%.*]] = shl i32 [[V1]], 1
; CHECK-NEXT: [[V3:%.*]] = and i32 [[V2]], 2
; CHECK-NEXT: ret i32 [[V3]]
@@ -944,14 +943,14 @@ define void @fold_phi_gep_phi_offset(ptr %init, ptr %end, i64 noundef %n) {
; CHECK-LABEL: define void @fold_phi_gep_phi_offset(
; CHECK-SAME: ptr [[INIT:%.*]], ptr [[END:%.*]], i64 noundef [[N:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
-; CHECK-NEXT: [[TMP0:%.*]] = freeze ptr [[INIT]]
; CHECK-NEXT: br label %[[LOOP:.*]]
; CHECK: [[LOOP]]:
-; CHECK-NEXT: [[I:%.*]] = phi ptr [ [[TMP0]], %[[ENTRY]] ], [ [[I_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT: [[I:%.*]] = phi ptr [ [[INIT]], %[[ENTRY]] ], [ [[I_NEXT_FR:%.*]], %[[LOOP]] ]
; CHECK-NEXT: [[OFF:%.*]] = phi i64 [ [[N]], %[[ENTRY]] ], [ [[OFF_NEXT:%.*]], %[[LOOP]] ]
; CHECK-NEXT: [[OFF_NEXT]] = shl i64 [[OFF]], 3
-; CHECK-NEXT: [[I_NEXT]] = getelementptr i8, ptr [[I]], i64 [[OFF_NEXT]]
-; CHECK-NEXT: [[COND:%.*]] = icmp eq ptr [[I_NEXT]], [[END]]
+; CHECK-NEXT: [[I_NEXT:%.*]] = getelementptr i8, ptr [[I]], i64 [[OFF_NEXT]]
+; CHECK-NEXT: [[I_NEXT_FR]] = freeze ptr [[I_NEXT]]
+; CHECK-NEXT: [[COND:%.*]] = icmp eq ptr [[I_NEXT_FR]], [[END]]
; CHECK-NEXT: br i1 [[COND]], label %[[LOOP]], label %[[EXIT:.*]]
; CHECK: [[EXIT]]:
; CHECK-NEXT: ret void
@@ -978,13 +977,13 @@ define void @fold_phi_gep_inbounds_phi_offset(ptr %init, ptr %end, i64 noundef %
; CHECK-LABEL: define void @fold_phi_gep_inbounds_phi_offset(
; CHECK-SAME: ptr [[INIT:%.*]], ptr [[END:%.*]], i64 noundef [[N:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
-; CHECK-NEXT: [[TMP0:%.*]] = freeze ptr [[INIT]]
; CHECK-NEXT: br label %[[LOOP:.*]]
; CHECK: [[LOOP]]:
-; CHECK-NEXT: [[I:%.*]] = phi ptr [ [[TMP0]], %[[ENTRY]] ], [ [[I_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT: [[I:%.*]] = phi ptr [ [[INIT]], %[[ENTRY]] ], [ [[I_NEXT:%.*]], %[[LOOP]] ]
; CHECK-NEXT: [[OFF:%.*]] = phi i64 [ [[N]], %[[ENTRY]] ], [ [[OFF_NEXT:%.*]], %[[LOOP]] ]
; CHECK-NEXT: [[OFF_NEXT]] = shl i64 [[OFF]], 3
-; CHECK-NEXT: [[I_NEXT]] = getelementptr i8, ptr [[I]], i64 [[OFF_NEXT]]
+; CHECK-NEXT: [[I_NEXT1:%.*]] = getelementptr inbounds i8, ptr [[I]], i64 [[OFF_NEXT]]
+; CHECK-NEXT: [[I_NEXT]] = freeze ptr [[I_NEXT1]]
; CHECK-NEXT: [[COND:%.*]] = icmp eq ptr [[I_NEXT]], [[END]]
; CHECK-NEXT: br i1 [[COND]], label %[[LOOP]], label %[[EXIT:.*]]
; CHECK: [[EXIT]]:
@@ -1011,14 +1010,13 @@ define void @fold_phi_gep_phi_offset_multiple(ptr %init, ptr %end, i64 %n) {
; CHECK-LABEL: define void @fold_phi_gep_phi_offset_multiple(
; CHECK-SAME: ptr [[INIT:%.*]], ptr [[END:%.*]], i64 [[N:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
-; CHECK-NEXT: [[TMP0:%.*]] = freeze ptr [[INIT]]
-; CHECK-NEXT: [[TMP1:%.*]] = freeze i64 [[N]]
; CHECK-NEXT: br label %[[LOOP:.*]]
; CHECK: [[LOOP]]:
-; CHECK-NEXT: [[I:%.*]] = phi ptr [ [[TMP0]], %[[ENTRY]] ], [ [[I_NEXT:%.*]], %[[LOOP]] ]
-; CHECK-NEXT: [[OFF:%.*]] = phi i64 [ [[TMP1]], %[[ENTRY]] ], [ [[OFF_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT: [[I:%.*]] = phi ptr [ [[INIT]], %[[ENTRY]] ], [ [[I_NEXT:%.*]], %[[LOOP]] ]
+; CHECK-NEXT: [[OFF:%.*]] = phi i64 [ [[N]], %[[ENTRY]] ], [ [[OFF_NEXT:%.*]], %[[LOOP]] ]
; CHECK-NEXT: [[OFF_NEXT]] = shl i64 [[OFF]], 3
-; CHECK-NEXT: [[I_NEXT]] = getelementptr i8, ptr [[I]], i64 [[OFF_NEXT]]
+; CHECK-NEXT: [[I_NEXT1:%.*]] = getelementptr inbounds i8, ptr [[I]], i64 [[OFF_NEXT]]
+; CHECK-NEXT: [[I_NEXT]] = freeze ptr [[I_NEXT1]]
; CHECK-NEXT: [[COND:%.*]] = icmp eq ptr [[I_NEXT]], [[END]]
; CHECK-NEXT: br i1 [[COND]], label %[[LOOP]], label %[[EXIT:.*]]
; CHECK: [[EXIT]]:
@@ -1671,13 +1669,13 @@ define i32 @pr171435_2(ptr noundef %arg, i32 noundef %arg1) "instcombine-no-veri
; CHECK: [[BB_7]]:
; CHECK-NEXT: br label %[[BB_8]]
; CHECK: [[BB_8]]:
-; CHECK-NEXT: [[PHI9:%.*]] = phi i32 [ [[CALL6]], %[[BB_5]] ], [ poison, %[[BB_7]] ]
-; CHECK-NEXT: [[PHI9_FR:%.*]] = freeze i32 [[PHI9]]
+; CHECK-NEXT: [[PHI9_FR:%.*]] = phi i32 [ [[CALL6]], %[[BB_5]] ], [ poison, %[[BB_7]] ]
; CHECK-NEXT: [[AND:%.*]] = and i32 [[PHI9_FR]], 1
; CHECK-NEXT: [[ASHR:%.*]] = lshr i32 [[PHI9_FR]], 1
; CHECK-NEXT: [[ADD:%.*]] = add nuw i32 [[ASHR]], [[AND]]
; CHECK-NEXT: [[ADD10:%.*]] = add i32 [[PHI]], [[ADD]]
-; CHECK-NEXT: [[AND11:%.*]] = and i32 [[ADD10]], 255
+; CHECK-NEXT: [[ADD10_FR:%.*]] = freeze i32 [[ADD10]]
+; CHECK-NEXT: [[AND11:%.*]] = and i32 [[ADD10_FR]], 255
; CHECK-NEXT: [[ICMP12:%.*]] = icmp eq i32 [[AND11]], 0
; CHECK-NEXT: [[SELECT:%.*]] = select i1 [[ICMP12]], i32 [[PHI]], i32 [[AND11]]
; CHECK-NEXT: br label %[[BB_13]]
diff --git a/llvm/test/Transforms/InstCombine/icmp.ll b/llvm/test/Transforms/InstCombine/icmp.ll
index 42a09420769f4..a6ad6f59dc0ec 100644
--- a/llvm/test/Transforms/InstCombine/icmp.ll
+++ b/llvm/test/Transforms/InstCombine/icmp.ll
@@ -5835,9 +5835,10 @@ entry:
define i1 @icmp_freeze_sext(i16 %x, i16 %y) {
; CHECK-LABEL: define i1 @icmp_freeze_sext(
; CHECK-SAME: i16 [[X:%.*]], i16 [[Y:%.*]]) {
-; CHECK-NEXT: [[Y_FR:%.*]] = freeze i16 [[Y]]
-; CHECK-NEXT: [[X_FR:%.*]] = freeze i16 [[X]]
-; CHECK-NEXT: [[CMP2:%.*]] = icmp uge i16 [[X_FR]], [[Y_FR]]
+; CHECK-NEXT: [[CMP1:%.*]] = icmp uge i16 [[X]], [[Y]]
+; CHECK-NEXT: [[CMP1_FR:%.*]] = freeze i1 [[CMP1]]
+; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i16 [[Y]], 0
+; CHECK-NEXT: [[CMP2:%.*]] = or i1 [[TMP1]], [[CMP1_FR]]
; CHECK-NEXT: ret i1 [[CMP2]]
;
%cmp1 = icmp uge i16 %x, %y
diff --git a/llvm/test/Transforms/InstCombine/nsw.ll b/llvm/test/Transforms/InstCombine/nsw.ll
index 4615ac0ec1ffb..b00f2e58add78 100644
--- a/llvm/test/Transforms/InstCombine/nsw.ll
+++ b/llvm/test/Transforms/InstCombine/nsw.ll
@@ -255,10 +255,9 @@ define i32 @sub_sub1_nsw_nsw(i32 %a, i32 %b, i32 %c) {
define i8 @neg_nsw_freeze(i8 %a1, i8 %a2) {
; CHECK-LABEL: @neg_nsw_freeze(
-; CHECK-NEXT: [[A1_FR:%.*]] = freeze i8 [[A1:%.*]]
-; CHECK-NEXT: [[A2_FR:%.*]] = freeze i8 [[A2:%.*]]
-; CHECK-NEXT: [[A_NEG:%.*]] = sub i8 [[A2_FR]], [[A1_FR]]
-; CHECK-NEXT: ret i8 [[A_NEG]]
+; CHECK-NEXT: [[A_NEG:%.*]] = sub nsw i8 [[A2:%.*]], [[A1:%.*]]
+; CHECK-NEXT: [[FR_NEG:%.*]] = freeze i8 [[A_NEG]]
+; CHECK-NEXT: ret i8 [[FR_NEG]]
;
%a = sub nsw i8 %a1, %a2
%fr = freeze i8 %a
diff --git a/llvm/test/Transforms/InstCombine/select-gep.ll b/llvm/test/Transforms/InstCombine/select-gep.ll
index 718133699a8a7..79287fd933cc0 100644
--- a/llvm/test/Transforms/InstCombine/select-gep.ll
+++ b/llvm/test/Transforms/InstCombine/select-gep.ll
@@ -304,10 +304,9 @@ define ptr @ptr_eq_replace_freeze1(ptr %p, ptr %q) {
define ptr @ptr_eq_replace_freeze2(ptr %p, ptr %q) {
; CHECK-LABEL: @ptr_eq_replace_freeze2(
-; CHECK-NEXT: [[P_FR:%.*]] = freeze ptr [[P:%.*]]
-; CHECK-NEXT: [[P_FR1:%.*]] = freeze ptr [[P1:%.*]]
-; CHECK-NEXT: [[CMP:%.*]] = icmp eq ptr [[P_FR1]], [[P_FR]]
-; CHECK-NEXT: [[SELECT_V:%.*]] = select i1 [[CMP]], ptr [[P_FR1]], ptr [[P_FR]]
+; CHECK-NEXT: [[CMP:%.*]] = icmp eq ptr [[P_FR1:%.*]], [[P_FR:%.*]]
+; CHECK-NEXT: [[CMP_FR:%.*]] = freeze i1 [[CMP]]
+; CHECK-NEXT: [[SELECT_V:%.*]] = select i1 [[CMP_FR]], ptr [[P_FR1]], ptr [[P_FR]]
; CHECK-NEXT: [[SELECT:%.*]] = getelementptr i8, ptr [[SELECT_V]], i64 16
; CHECK-NEXT: ret ptr [[SELECT]]
;
diff --git a/llvm/test/Transforms/InstCombine/select.ll b/llvm/test/Transforms/InstCombine/select.ll
index 6076a18b6501c..d76b6dc489712 100644
--- a/llvm/test/Transforms/InstCombine/select.ll
+++ b/llvm/test/Transforms/InstCombine/select.ll
@@ -2847,8 +2847,10 @@ define void @cond_freeze_multipleuses(i8 %x, i8 %y) {
define i32 @select_freeze_icmp_eq(i32 %x, i32 %y) {
; CHECK-LABEL: define i32 @select_freeze_icmp_eq(
; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
-; CHECK-NEXT: [[Y_FR:%.*]] = freeze i32 [[Y]]
-; CHECK-NEXT: ret i32 [[Y_FR]]
+; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[X]], [[Y]]
+; CHECK-NEXT: [[C_FR:%.*]] = freeze i1 [[C]]
+; CHECK-NEXT: [[V:%.*]] = select i1 [[C_FR]], i32 [[X]], i32 [[Y]]
+; CHECK-NEXT: ret i32 [[V]]
;
%c = icmp eq i32 %x, %y
%c.fr = freeze i1 %c
@@ -2859,8 +2861,10 @@ define i32 @select_freeze_icmp_eq(i32 %x, i32 %y) {
define i32 @select_freeze_icmp_ne(i32 %x, i32 %y) {
; CHECK-LABEL: define i32 @select_freeze_icmp_ne(
; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
-; CHECK-NEXT: [[X_FR:%.*]] = freeze i32 [[X]]
-; CHECK-NEXT: ret i32 [[X_FR]]
+; CHECK-NEXT: [[C:%.*]] = icmp ne i32 [[X]], [[Y]]
+; CHECK-NEXT: [[C_FR:%.*]] = freeze i1 [[C]]
+; CHECK-NEXT: [[V:%.*]] = select i1 [[C_FR]], i32 [[X]], i32 [[Y]]
+; CHECK-NEXT: ret i32 [[V]]
;
%c = icmp ne i32 %x, %y
%c.fr = freeze i1 %c
@@ -2871,9 +2875,9 @@ define i32 @select_freeze_icmp_ne(i32 %x, i32 %y) {
define i32 @select_freeze_icmp_else(i32 %x, i32 %y) {
; CHECK-LABEL: define i32 @select_freeze_icmp_else(
; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
-; CHECK-NEXT: [[Y_FR:%.*]] = freeze i32 [[Y]]
-; CHECK-NEXT: [[X_FR:%.*]] = freeze i32 [[X]]
-; CHECK-NEXT: [[V:%.*]] = call i32 @llvm.umin.i32(i32 [[X_FR]], i32 [[Y_FR]])
+; CHECK-NEXT: [[C:%.*]] = icmp ult i32 [[X]], [[Y]]
+; CHECK-NEXT: [[C_FR:%.*]] = freeze i1 [[C]]
+; CHECK-NEXT: [[V:%.*]] = select i1 [[C_FR]], i32 [[X]], i32 [[Y]]
; CHECK-NEXT: ret i32 [[V]]
;
%c = icmp ult i32 %x, %y
@@ -2887,9 +2891,9 @@ declare void @use_i1_i32(i1, i32)
define void @select_freeze_icmp_multuses(i32 %x, i32 %y) {
; CHECK-LABEL: define void @select_freeze_icmp_multuses(
; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
-; CHECK-NEXT: [[Y_FR:%.*]] = freeze i32 [[Y]]
-; CHECK-NEXT: [[V:%.*]] = freeze i32 [[X]]
-; CHECK-NEXT: [[C_FR:%.*]] = icmp ne i32 [[V]], [[Y_FR]]
+; CHECK-NEXT: [[C:%.*]] = icmp ne i32 [[X]], [[Y]]
+; CHECK-NEXT: [[C_FR:%.*]] = freeze i1 [[C]]
+; CHECK-NEXT: [[V:%.*]] = select i1 [[C_FR]], i32 [[X]], i32 [[Y]]
; CHECK-NEXT: call void @use_i1_i32(i1 [[C_FR]], i32 [[V]])
; CHECK-NEXT: ret void
;
diff --git a/llvm/test/Transforms/InstCombine/sub-of-negatible-inseltpoison.ll b/llvm/test/Transforms/InstCombine/sub-of-negatible-inseltpoison.ll
index 109669e91d22f..537497110cd8a 100644
--- a/llvm/test/Transforms/InstCombine/sub-of-negatible-inseltpoison.ll
+++ b/llvm/test/Transforms/InstCombine/sub-of-negatible-inseltpoison.ll
@@ -1446,9 +1446,8 @@ define i8 @dont_negate_ordinary_select(i8 %x, i8 %y, i8 %z, i1 %c) {
define i4 @negate_freeze(i4 %x, i4 %y, i4 %z) {
; CHECK-LABEL: define i4 @negate_freeze(
; CHECK-SAME: i4 [[X:%.*]], i4 [[Y:%.*]], i4 [[Z:%.*]]) {
-; CHECK-NEXT: [[X_FR:%.*]] = freeze i4 [[X]]
-; CHECK-NEXT: [[Y_FR:%.*]] = freeze i4 [[Y]]
-; CHECK-NEXT: [[T1_NEG:%.*]] = sub i4 [[Y_FR]], [[X_FR]]
+; CHECK-NEXT: [[T0_NEG:%.*]] = sub i4 [[Y]], [[X]]
+; CHECK-NEXT: [[T1_NEG:%.*]] = freeze i4 [[T0_NEG]]
; CHECK-NEXT: [[T2:%.*]] = add i4 [[T1_NEG]], [[Z]]
; CHECK-NEXT: ret i4 [[T2]]
;
@@ -1460,9 +1459,8 @@ define i4 @negate_freeze(i4 %x, i4 %y, i4 %z) {
define i4 @negate_freeze_extrause(i4 %x, i4 %y, i4 %z) {
; CHECK-LABEL: define i4 @negate_freeze_extrause(
; CHECK-SAME: i4 [[X:%.*]], i4 [[Y:%.*]], i4 [[Z:%.*]]) {
-; CHECK-NEXT: [[X_FR:%.*]] = freeze i4 [[X]]
-; CHECK-NEXT: [[Y_FR:%.*]] = freeze i4 [[Y]]
-; CHECK-NEXT: [[T1:%.*]] = sub i4 [[X_FR]], [[Y_FR]]
+; CHECK-NEXT: [[T0:%.*]] = sub i4 [[X]], [[Y]]
+; CHECK-NEXT: [[T1:%.*]] = freeze i4 [[T0]]
; CHECK-NEXT: call void @use4(i4 [[T1]])
; CHECK-NEXT: [[T2:%.*]] = sub i4 [[Z]], [[T1]]
; CHECK-NEXT: ret i4 [[T2]]
diff --git a/llvm/test/Transforms/InstCombine/sub-of-negatible.ll b/llvm/test/Transforms/InstCombine/sub-of-negatible.ll
index aad006de0e361..3a91c14e8ba10 100644
--- a/llvm/test/Transforms/InstCombine/sub-of-negatible.ll
+++ b/llvm/test/Transforms/InstCombine/sub-of-negatible.ll
@@ -1543,9 +1543,8 @@ define <2 x i32> @negate_select_of_negation_poison(<2 x i1> %c, <2 x i32> %x) {
define i4 @negate_freeze(i4 %x, i4 %y, i4 %z) {
; CHECK-LABEL: define i4 @negate_freeze(
; CHECK-SAME: i4 [[X:%.*]], i4 [[Y:%.*]], i4 [[Z:%.*]]) {
-; CHECK-NEXT: [[X_FR:%.*]] = freeze i4 [[X]]
-; CHECK-NEXT: [[Y_FR:%.*]] = freeze i4 [[Y]]
-; CHECK-NEXT: [[T1_NEG:%.*]] = sub i4 [[Y_FR]], [[X_FR]]
+; CHECK-NEXT: [[T0_NEG:%.*]] = sub i4 [[Y]], [[X]]
+; CHECK-NEXT: [[T1_NEG:%.*]] = freeze i4 [[T0_NEG]]
; CHECK-NEXT: [[T2:%.*]] = add i4 [[T1_NEG]], [[Z]]
; CHECK-NEXT: ret i4 [[T2]]
;
@@ -1557,9 +1556,8 @@ define i4 @negate_freeze(i4 %x, i4 %y, i4 %z) {
define i4 @negate_freeze_extrause(i4 %x, i4 %y, i4 %z) {
; CHECK-LABEL: define i4 @negate_freeze_extrause(
; CHECK-SAME: i4 [[X:%.*]], i4 [[Y:%.*]], i4 [[Z:%.*]]) {
-; CHECK-NEXT: [[X_FR:%.*]] = freeze i4 [[X]]
-; CHECK-NEXT: [[Y_FR:%.*]] = freeze i4 [[Y]]
-; CHECK-NEXT: [[T1:%.*]] = sub i4 [[X_FR]], [[Y_FR]]
+; CHECK-NEXT: [[T0:%.*]] = sub i4 [[X]], [[Y]]
+; CHECK-NEXT: [[T1:%.*]] = freeze i4 [[T0]]
; CHECK-NEXT: call void @use4(i4 [[T1]])
; CHECK-NEXT: [[T2:%.*]] = sub i4 [[Z]], [[T1]]
; CHECK-NEXT: ret i4 [[T2]]
diff --git a/llvm/test/Transforms/InstCombine/urem-via-cmp-select.ll b/llvm/test/Transforms/InstCombine/urem-via-cmp-select.ll
index 16981d0a39ad2..c74c37fa8facb 100644
--- a/llvm/test/Transforms/InstCombine/urem-via-cmp-select.ll
+++ b/llvm/test/Transforms/InstCombine/urem-via-cmp-select.ll
@@ -96,11 +96,10 @@ define i8 @urem_assume_with_unexpected_const(i8 %x, i8 %n) {
define i8 @urem_without_assume(i8 %arg, i8 %arg2) {
; CHECK-LABEL: define i8 @urem_without_assume(
; CHECK-S...
[truncated]
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nikic
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Feb 22, 2026
This reverts commit f8f6965. This is causing infinte loops interacting with other transforms. See discussion on llvm#182647 .
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Failed to cherry-pick: bd3b163 Please manually backport the fix and push it to your github fork. Once this is done, please create a pull request |
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Feb 23, 2026
…llvm#182769) This reverts commit f8f6965. This is causing infinite loops interacting with other transforms. See discussion on llvm#182647 . (cherry picked from commit bd3b163)
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This reverts commit f8f6965.
This is causing infinte loops interacting with other transforms. See discussion on #182647 .