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[SCEV] Preserve divisor info when adding guard info for ICMP_NE via Sub. #163250

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[SCEV] Preserve divisor info when adding guard info for ICMP_NE via Sub. #163250

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@fhahn fhahn commented Oct 13, 2025

Follow-up to #160500 to
preserve divisibiltiy info when creating the UMax.

fhahn added 3 commits October 13, 2025 20:15
@fhahn
Collect guard info for ICMP NE w/o constants.
ca3fbd0 
When collecting information from loop guards, use UMax(1, %b - %a) for
ICMP NE %a, %b, if neither are constant.

This improves results in some cases, and will be even more useful
together with
 * llvm#160012
 * llvm#159942

https://alive2.llvm.org/ce/z/YyBvoT
@fhahn
!fixup add both
abd178c
@fhahn
[SCEV] Preserve divisor info when adding guard info for ICMP_NE via Sub.
b0ccf0c 
Follow-up to llvm#160500 to
preserve divisibiltiy info when creating the UMax.
@llvmbot llvmbot added llvm:analysis Includes value tracking, cost tables and constant folding llvm:transforms labels Oct 13, 2025
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llvmbot commented Oct 13, 2025 •
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@llvm/pr-subscribers-llvm-analysis

@llvm/pr-subscribers-llvm-transforms

Author: Florian Hahn (fhahn)

Changes

Follow-up to #160500 to
preserve divisibiltiy info when creating the UMax.

Full diff: https://github.com/llvm/llvm-project/pull/163250.diff

5 Files Affected:

  • (modified) llvm/lib/Analysis/ScalarEvolution.cpp (+16)
  • (modified) llvm/test/Analysis/ScalarEvolution/max-backedge-taken-count-guard-info.ll (+4-4)
  • (modified) llvm/test/Analysis/ScalarEvolution/ptrtoint.ll (+10-10)
  • (modified) llvm/test/Transforms/IndVarSimplify/pointer-loop-guards.ll (+1-1)
  • (modified) llvm/test/Transforms/LoopUnroll/scevunroll.ll (+1-2)
diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index 00c3dbbf3e800..3d99f4cadf3c2 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -15827,6 +15827,22 @@ void ScalarEvolution::LoopGuards::collectFromBlock(
           const SCEV *OneAlignedUp =
               GetNextSCEVDividesByDivisor(One, DividesBy);
           To = SE.getUMaxExpr(FromRewritten, OneAlignedUp);
+        } else {
+          if (LHS->getType()->isPointerTy()) {
+            LHS = SE.getLosslessPtrToIntExpr(LHS);
+            RHS = SE.getLosslessPtrToIntExpr(RHS);
+            if (isa<SCEVCouldNotCompute>(LHS) || isa<SCEVCouldNotCompute>(RHS))
+              break;
+          }
+          auto AddSubRewrite = [&](const SCEV *A, const SCEV *B) {
+            const SCEV *Sub = SE.getMinusSCEV(A, B);
+            const SCEV *OneAlignedUp = GetNextSCEVDividesByDivisor(
+                SE.getOne(From->getType()), SE.getConstantMultiple(Sub));
+            AddRewrite(Sub, Sub, SE.getUMaxExpr(Sub, OneAlignedUp));
+          };
+          AddSubRewrite(LHS, RHS);
+          AddSubRewrite(RHS, LHS);
+          continue;
         }
         break;
       default:
diff --git a/llvm/test/Analysis/ScalarEvolution/max-backedge-taken-count-guard-info.ll b/llvm/test/Analysis/ScalarEvolution/max-backedge-taken-count-guard-info.ll
index 4024c986dd11d..d5a2181e9bc5e 100644
--- a/llvm/test/Analysis/ScalarEvolution/max-backedge-taken-count-guard-info.ll
+++ b/llvm/test/Analysis/ScalarEvolution/max-backedge-taken-count-guard-info.ll
@@ -1431,7 +1431,7 @@ define void @ptr_induction_early_exit_eq_1_with_align_on_load(ptr %a, ptr %b, pt
 ; CHECK-NEXT:  Loop %loop: <multiple exits> Unpredictable backedge-taken count.
 ; CHECK-NEXT:    exit count for loop: ***COULDNOTCOMPUTE***
 ; CHECK-NEXT:    exit count for loop.inc: ((-8 + (-1 * (ptrtoint ptr %a_ to i64)) + (ptrtoint ptr %b_ to i64)) /u 8)
-; CHECK-NEXT:  Loop %loop: constant max backedge-taken count is i64 2305843009213693951
+; CHECK-NEXT:  Loop %loop: constant max backedge-taken count is i64 2305843009213693950
 ; CHECK-NEXT:  Loop %loop: symbolic max backedge-taken count is ((-8 + (-1 * (ptrtoint ptr %a_ to i64)) + (ptrtoint ptr %b_ to i64)) /u 8)
 ; CHECK-NEXT:    symbolic max exit count for loop: ***COULDNOTCOMPUTE***
 ; CHECK-NEXT:    symbolic max exit count for loop.inc: ((-8 + (-1 * (ptrtoint ptr %a_ to i64)) + (ptrtoint ptr %b_ to i64)) /u 8)
@@ -1470,7 +1470,7 @@ define void @ptr_induction_early_exit_eq_1_with_align_on_arguments(ptr align 8 %
 ; CHECK-NEXT:  Loop %loop: <multiple exits> Unpredictable backedge-taken count.
 ; CHECK-NEXT:    exit count for loop: ***COULDNOTCOMPUTE***
 ; CHECK-NEXT:    exit count for loop.inc: ((-8 + (-1 * (ptrtoint ptr %a to i64)) + (ptrtoint ptr %b to i64)) /u 8)
-; CHECK-NEXT:  Loop %loop: constant max backedge-taken count is i64 2305843009213693951
+; CHECK-NEXT:  Loop %loop: constant max backedge-taken count is i64 2305843009213693950
 ; CHECK-NEXT:  Loop %loop: symbolic max backedge-taken count is ((-8 + (-1 * (ptrtoint ptr %a to i64)) + (ptrtoint ptr %b to i64)) /u 8)
 ; CHECK-NEXT:    symbolic max exit count for loop: ***COULDNOTCOMPUTE***
 ; CHECK-NEXT:    symbolic max exit count for loop.inc: ((-8 + (-1 * (ptrtoint ptr %a to i64)) + (ptrtoint ptr %b to i64)) /u 8)
@@ -1511,7 +1511,7 @@ define void @ptr_induction_early_exit_eq_1_align_assumption_1(ptr %a, ptr %b, pt
 ; CHECK-NEXT:  Loop %loop: <multiple exits> Unpredictable backedge-taken count.
 ; CHECK-NEXT:    exit count for loop: ***COULDNOTCOMPUTE***
 ; CHECK-NEXT:    exit count for loop.inc: ((-8 + (-1 * (ptrtoint ptr %a_ to i64)) + (ptrtoint ptr %b_ to i64)) /u 8)
-; CHECK-NEXT:  Loop %loop: constant max backedge-taken count is i64 2305843009213693951
+; CHECK-NEXT:  Loop %loop: constant max backedge-taken count is i64 2305843009213693950
 ; CHECK-NEXT:  Loop %loop: symbolic max backedge-taken count is ((-8 + (-1 * (ptrtoint ptr %a_ to i64)) + (ptrtoint ptr %b_ to i64)) /u 8)
 ; CHECK-NEXT:    symbolic max exit count for loop: ***COULDNOTCOMPUTE***
 ; CHECK-NEXT:    symbolic max exit count for loop.inc: ((-8 + (-1 * (ptrtoint ptr %a_ to i64)) + (ptrtoint ptr %b_ to i64)) /u 8)
@@ -1556,7 +1556,7 @@ define void @ptr_induction_early_exit_eq_1_align_assumption_2(ptr %a, ptr %b, pt
 ; CHECK-NEXT:  Loop %loop: <multiple exits> Unpredictable backedge-taken count.
 ; CHECK-NEXT:    exit count for loop: ***COULDNOTCOMPUTE***
 ; CHECK-NEXT:    exit count for loop.inc: ((-8 + (-1 * (ptrtoint ptr %a_ to i64)) + (ptrtoint ptr %b_ to i64)) /u 8)
-; CHECK-NEXT:  Loop %loop: constant max backedge-taken count is i64 2305843009213693951
+; CHECK-NEXT:  Loop %loop: constant max backedge-taken count is i64 2305843009213693950
 ; CHECK-NEXT:  Loop %loop: symbolic max backedge-taken count is ((-8 + (-1 * (ptrtoint ptr %a_ to i64)) + (ptrtoint ptr %b_ to i64)) /u 8)
 ; CHECK-NEXT:    symbolic max exit count for loop: ***COULDNOTCOMPUTE***
 ; CHECK-NEXT:    symbolic max exit count for loop.inc: ((-8 + (-1 * (ptrtoint ptr %a_ to i64)) + (ptrtoint ptr %b_ to i64)) /u 8)
diff --git a/llvm/test/Analysis/ScalarEvolution/ptrtoint.ll b/llvm/test/Analysis/ScalarEvolution/ptrtoint.ll
index acac2c98ad174..0c1f37bf58601 100644
--- a/llvm/test/Analysis/ScalarEvolution/ptrtoint.ll
+++ b/llvm/test/Analysis/ScalarEvolution/ptrtoint.ll
@@ -382,7 +382,7 @@ define void @pr46786_c26_char(ptr %arg, ptr %arg1, ptr %arg2) {
 ; X64-NEXT:    %i9 = ptrtoint ptr %i7 to i64
 ; X64-NEXT:    --> {(ptrtoint ptr %arg to i64),+,1}<nuw><%bb6> U: full-set S: full-set Exits: (-1 + (ptrtoint ptr %arg1 to i64)) LoopDispositions: { %bb6: Computable }
 ; X64-NEXT:    %i10 = sub i64 %i9, %i4
-; X64-NEXT:    --> {0,+,1}<nuw><%bb6> U: full-set S: full-set Exits: (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64)) LoopDispositions: { %bb6: Computable }
+; X64-NEXT:    --> {0,+,1}<nuw><%bb6> U: [0,-1) S: [0,-1) Exits: (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64)) LoopDispositions: { %bb6: Computable }
 ; X64-NEXT:    %i11 = getelementptr inbounds i8, ptr %arg2, i64 %i10
 ; X64-NEXT:    --> {%arg2,+,1}<nw><%bb6> U: full-set S: full-set Exits: (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64) + %arg2) LoopDispositions: { %bb6: Computable }
 ; X64-NEXT:    %i12 = load i8, ptr %i11, align 1
@@ -393,7 +393,7 @@ define void @pr46786_c26_char(ptr %arg, ptr %arg1, ptr %arg2) {
 ; X64-NEXT:    --> {(1 + %arg),+,1}<nuw><%bb6> U: full-set S: full-set Exits: ((-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64) + %arg) LoopDispositions: { %bb6: Computable }
 ; X64-NEXT:  Determining loop execution counts for: @pr46786_c26_char
 ; X64-NEXT:  Loop %bb6: backedge-taken count is (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64))
-; X64-NEXT:  Loop %bb6: constant max backedge-taken count is i64 -1
+; X64-NEXT:  Loop %bb6: constant max backedge-taken count is i64 -2
 ; X64-NEXT:  Loop %bb6: symbolic max backedge-taken count is (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64))
 ; X64-NEXT:  Loop %bb6: Trip multiple is 1
 ;
@@ -406,9 +406,9 @@ define void @pr46786_c26_char(ptr %arg, ptr %arg1, ptr %arg2) {
 ; X32-NEXT:    %i8 = load i8, ptr %i7, align 1
 ; X32-NEXT:    --> %i8 U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %bb6: Variant }
 ; X32-NEXT:    %i9 = ptrtoint ptr %i7 to i64
-; X32-NEXT:    --> {(zext i32 (ptrtoint ptr %arg to i32) to i64),+,1}<nuw><%bb6> U: [0,8589934591) S: [0,8589934591) Exits: ((zext i32 (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32)) to i64) + (zext i32 (ptrtoint ptr %arg to i32) to i64)) LoopDispositions: { %bb6: Computable }
+; X32-NEXT:    --> {(zext i32 (ptrtoint ptr %arg to i32) to i64),+,1}<nuw><%bb6> U: [0,8589934590) S: [0,8589934590) Exits: ((zext i32 (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32)) to i64) + (zext i32 (ptrtoint ptr %arg to i32) to i64)) LoopDispositions: { %bb6: Computable }
 ; X32-NEXT:    %i10 = sub i64 %i9, %i4
-; X32-NEXT:    --> {0,+,1}<nuw><%bb6> U: [0,4294967296) S: [0,4294967296) Exits: (zext i32 (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32)) to i64) LoopDispositions: { %bb6: Computable }
+; X32-NEXT:    --> {0,+,1}<nuw><%bb6> U: [0,4294967295) S: [0,4294967295) Exits: (zext i32 (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32)) to i64) LoopDispositions: { %bb6: Computable }
 ; X32-NEXT:    %i11 = getelementptr inbounds i8, ptr %arg2, i64 %i10
 ; X32-NEXT:    --> {%arg2,+,1}<%bb6> U: full-set S: full-set Exits: (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32) + %arg2) LoopDispositions: { %bb6: Computable }
 ; X32-NEXT:    %i12 = load i8, ptr %i11, align 1
@@ -419,7 +419,7 @@ define void @pr46786_c26_char(ptr %arg, ptr %arg1, ptr %arg2) {
 ; X32-NEXT:    --> {(1 + %arg),+,1}<nuw><%bb6> U: full-set S: full-set Exits: ((-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32) + %arg) LoopDispositions: { %bb6: Computable }
 ; X32-NEXT:  Determining loop execution counts for: @pr46786_c26_char
 ; X32-NEXT:  Loop %bb6: backedge-taken count is (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32))
-; X32-NEXT:  Loop %bb6: constant max backedge-taken count is i32 -1
+; X32-NEXT:  Loop %bb6: constant max backedge-taken count is i32 -2
 ; X32-NEXT:  Loop %bb6: symbolic max backedge-taken count is (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32))
 ; X32-NEXT:  Loop %bb6: Trip multiple is 1
 ;
@@ -459,7 +459,7 @@ define void @pr46786_c26_char_cmp_ops_swapped(ptr %arg, ptr %arg1, ptr %arg2) {
 ; X64-NEXT:    %i9 = ptrtoint ptr %i7 to i64
 ; X64-NEXT:    --> {(ptrtoint ptr %arg to i64),+,1}<nuw><%bb6> U: full-set S: full-set Exits: (-1 + (ptrtoint ptr %arg1 to i64)) LoopDispositions: { %bb6: Computable }
 ; X64-NEXT:    %i10 = sub i64 %i9, %i4
-; X64-NEXT:    --> {0,+,1}<nuw><%bb6> U: full-set S: full-set Exits: (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64)) LoopDispositions: { %bb6: Computable }
+; X64-NEXT:    --> {0,+,1}<nuw><%bb6> U: [0,-1) S: [0,-1) Exits: (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64)) LoopDispositions: { %bb6: Computable }
 ; X64-NEXT:    %i11 = getelementptr inbounds i8, ptr %arg2, i64 %i10
 ; X64-NEXT:    --> {%arg2,+,1}<nw><%bb6> U: full-set S: full-set Exits: (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64) + %arg2) LoopDispositions: { %bb6: Computable }
 ; X64-NEXT:    %i12 = load i8, ptr %i11, align 1
@@ -470,7 +470,7 @@ define void @pr46786_c26_char_cmp_ops_swapped(ptr %arg, ptr %arg1, ptr %arg2) {
 ; X64-NEXT:    --> {(1 + %arg),+,1}<nuw><%bb6> U: full-set S: full-set Exits: ((-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64) + %arg) LoopDispositions: { %bb6: Computable }
 ; X64-NEXT:  Determining loop execution counts for: @pr46786_c26_char_cmp_ops_swapped
 ; X64-NEXT:  Loop %bb6: backedge-taken count is (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64))
-; X64-NEXT:  Loop %bb6: constant max backedge-taken count is i64 -1
+; X64-NEXT:  Loop %bb6: constant max backedge-taken count is i64 -2
 ; X64-NEXT:  Loop %bb6: symbolic max backedge-taken count is (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64))
 ; X64-NEXT:  Loop %bb6: Trip multiple is 1
 ;
@@ -483,9 +483,9 @@ define void @pr46786_c26_char_cmp_ops_swapped(ptr %arg, ptr %arg1, ptr %arg2) {
 ; X32-NEXT:    %i8 = load i8, ptr %i7, align 1
 ; X32-NEXT:    --> %i8 U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %bb6: Variant }
 ; X32-NEXT:    %i9 = ptrtoint ptr %i7 to i64
-; X32-NEXT:    --> {(zext i32 (ptrtoint ptr %arg to i32) to i64),+,1}<nuw><%bb6> U: [0,8589934591) S: [0,8589934591) Exits: ((zext i32 (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32)) to i64) + (zext i32 (ptrtoint ptr %arg to i32) to i64)) LoopDispositions: { %bb6: Computable }
+; X32-NEXT:    --> {(zext i32 (ptrtoint ptr %arg to i32) to i64),+,1}<nuw><%bb6> U: [0,8589934590) S: [0,8589934590) Exits: ((zext i32 (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32)) to i64) + (zext i32 (ptrtoint ptr %arg to i32) to i64)) LoopDispositions: { %bb6: Computable }
 ; X32-NEXT:    %i10 = sub i64 %i9, %i4
-; X32-NEXT:    --> {0,+,1}<nuw><%bb6> U: [0,4294967296) S: [0,4294967296) Exits: (zext i32 (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32)) to i64) LoopDispositions: { %bb6: Computable }
+; X32-NEXT:    --> {0,+,1}<nuw><%bb6> U: [0,4294967295) S: [0,4294967295) Exits: (zext i32 (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32)) to i64) LoopDispositions: { %bb6: Computable }
 ; X32-NEXT:    %i11 = getelementptr inbounds i8, ptr %arg2, i64 %i10
 ; X32-NEXT:    --> {%arg2,+,1}<%bb6> U: full-set S: full-set Exits: (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32) + %arg2) LoopDispositions: { %bb6: Computable }
 ; X32-NEXT:    %i12 = load i8, ptr %i11, align 1
@@ -496,7 +496,7 @@ define void @pr46786_c26_char_cmp_ops_swapped(ptr %arg, ptr %arg1, ptr %arg2) {
 ; X32-NEXT:    --> {(1 + %arg),+,1}<nuw><%bb6> U: full-set S: full-set Exits: ((-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32) + %arg) LoopDispositions: { %bb6: Computable }
 ; X32-NEXT:  Determining loop execution counts for: @pr46786_c26_char_cmp_ops_swapped
 ; X32-NEXT:  Loop %bb6: backedge-taken count is (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32))
-; X32-NEXT:  Loop %bb6: constant max backedge-taken count is i32 -1
+; X32-NEXT:  Loop %bb6: constant max backedge-taken count is i32 -2
 ; X32-NEXT:  Loop %bb6: symbolic max backedge-taken count is (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32))
 ; X32-NEXT:  Loop %bb6: Trip multiple is 1
 ;
diff --git a/llvm/test/Transforms/IndVarSimplify/pointer-loop-guards.ll b/llvm/test/Transforms/IndVarSimplify/pointer-loop-guards.ll
index 89b132e981899..9371fe24be05d 100644
--- a/llvm/test/Transforms/IndVarSimplify/pointer-loop-guards.ll
+++ b/llvm/test/Transforms/IndVarSimplify/pointer-loop-guards.ll
@@ -18,7 +18,7 @@ define i64 @test_ptr_compare_guard(ptr %start, ptr %end) {
 ; CHECK-NEXT:    br i1 [[C_1]], label %[[LOOP_LATCH]], label %[[EXIT_LOOPEXIT:.*]]
 ; CHECK:       [[LOOP_LATCH]]:
 ; CHECK-NEXT:    [[PTR_IV_NEXT]] = getelementptr i8, ptr [[PTR_IV]], i64 1
-; CHECK-NEXT:    [[I64_IV_NEXT]] = add i64 [[I64_IV]], 1
+; CHECK-NEXT:    [[I64_IV_NEXT]] = add nuw i64 [[I64_IV]], 1
 ; CHECK-NEXT:    [[C_2:%.*]] = icmp eq ptr [[PTR_IV_NEXT]], [[END]]
 ; CHECK-NEXT:    br i1 [[C_2]], label %[[EXIT_LOOPEXIT]], label %[[LOOP_HEADER]]
 ; CHECK:       [[EXIT_LOOPEXIT]]:
diff --git a/llvm/test/Transforms/LoopUnroll/scevunroll.ll b/llvm/test/Transforms/LoopUnroll/scevunroll.ll
index fa55eab062198..bc63f79296a30 100644
--- a/llvm/test/Transforms/LoopUnroll/scevunroll.ll
+++ b/llvm/test/Transforms/LoopUnroll/scevunroll.ll
@@ -465,8 +465,7 @@ define void @peel_int_eq_condition(i32 %start) {
 ; CHECK-NEXT:    br label [[LOOP:%.*]]
 ; CHECK:       loop:
 ; CHECK-NEXT:    [[IV:%.*]] = phi i32 [ [[IV_NEXT_PEEL]], [[ENTRY_PEEL_NEWPH]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ]
-; CHECK-NEXT:    [[C_0:%.*]] = icmp eq i32 [[IV]], [[START]]
-; CHECK-NEXT:    br i1 [[C_0]], label [[IF_THEN:%.*]], label [[LOOP_LATCH]]
+; CHECK-NEXT:    br i1 false, label [[IF_THEN:%.*]], label [[LOOP_LATCH]]
 ; CHECK:       if.then:
 ; CHECK-NEXT:    call void @fn(i32 [[IV]])
 ; CHECK-NEXT:    br label [[LOOP_LATCH]]

This was referenced Oct 13, 2025
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fhahn commented Oct 13, 2025

There's no impact on llvm-opt-benchmarks (dtcxzyw/llvm-opt-benchmark#2925) over #160500 (dtcxzyw/llvm-opt-benchmark#2859), but it will help together with #163260 & #159942

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