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merged 8 commits into from
Sep 30, 2025
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[NFC] [IndVarSimplify] add overflowing tests #159877

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9f883c0
[𝘀𝗽𝗿] initial version
fmayer Sep 19, 2025
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[𝘀𝗽𝗿] changes to main this commit is based on
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[𝘀𝗽𝗿] changes introduced through rebase
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268 changes: 244 additions & 24 deletions llvm/test/Transforms/IndVarSimplify/X86/overflow-intrinsics.ll
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Original file line number Diff line number Diff line change
@@ -1,10 +1,29 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
; RUN: opt -S -passes=indvars < %s | FileCheck %s

target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

define void @f_sadd(ptr %a) {
; CHECK-LABEL: @f_sadd(
; CHECK-LABEL: define void @f_sadd(
; CHECK-SAME: ptr [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: br label %[[FOR_BODY:.*]]
; CHECK: [[FOR_COND_CLEANUP:.*]]:
; CHECK-NEXT: ret void
; CHECK: [[FOR_BODY]]:
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], %[[CONT:.*]] ], [ 0, %[[ENTRY]] ]
; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 [[INDVARS_IV]]
; CHECK-NEXT: store i8 0, ptr [[ARRAYIDX]], align 1
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
; CHECK-NEXT: br i1 false, label %[[TRAP:.*]], label %[[CONT]], !nosanitize [[META0:![0-9]+]]
; CHECK: [[TRAP]]:
; CHECK-NEXT: tail call void @llvm.trap(), !nosanitize [[META0]]
; CHECK-NEXT: unreachable, !nosanitize [[META0]]
; CHECK: [[CONT]]:
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i64 [[INDVARS_IV_NEXT]], 16
; CHECK-NEXT: br i1 [[EXITCOND]], label %[[FOR_BODY]], label %[[FOR_COND_CLEANUP]]
;
entry:
br label %for.body

Expand All @@ -18,9 +37,6 @@ for.body: ; preds = %entry, %cont
store i8 0, ptr %arrayidx, align 1
%0 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %i.04, i32 1)
%1 = extractvalue { i32, i1 } %0, 1
; CHECK: for.body:
; CHECK-NOT: @llvm.sadd.with.overflow
; CHECK: br i1 false, label %trap, label %cont, !nosanitize !0
br i1 %1, label %trap, label %cont, !nosanitize !{}

trap: ; preds = %for.body
Expand All @@ -33,8 +49,71 @@ cont: ; preds = %for.body
br i1 %cmp, label %for.body, label %for.cond.cleanup
}

define void @f_sadd_overflow(ptr %a) {
; CHECK-LABEL: define void @f_sadd_overflow(
; CHECK-SAME: ptr [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: br label %[[FOR_BODY:.*]]
; CHECK: [[FOR_COND_CLEANUP:.*]]:
; CHECK-NEXT: ret void
; CHECK: [[FOR_BODY]]:
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], %[[CONT:.*]] ], [ 2147483645, %[[ENTRY]] ]
; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 [[INDVARS_IV]]
; CHECK-NEXT: store i8 0, ptr [[ARRAYIDX]], align 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp eq i64 [[INDVARS_IV]], 2147483647
; CHECK-NEXT: br i1 [[EXITCOND]], label %[[TRAP:.*]], label %[[CONT]], !nosanitize [[META0]]
; CHECK: [[TRAP]]:
; CHECK-NEXT: tail call void @llvm.trap(), !nosanitize [[META0]]
; CHECK-NEXT: unreachable, !nosanitize [[META0]]
; CHECK: [[CONT]]:
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
; CHECK-NEXT: br i1 true, label %[[FOR_BODY]], label %[[FOR_COND_CLEANUP]]
;
entry:
br label %for.body

for.cond.cleanup: ; preds = %cont
ret void

for.body: ; preds = %entry, %cont
%i.04 = phi i32 [ 2147483645, %entry ], [ %2, %cont ]
%idxprom = sext i32 %i.04 to i64
%arrayidx = getelementptr inbounds i8, ptr %a, i64 %idxprom
store i8 0, ptr %arrayidx, align 1
%0 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %i.04, i32 1)
%1 = extractvalue { i32, i1 } %0, 1
br i1 %1, label %trap, label %cont, !nosanitize !{}

trap: ; preds = %for.body
tail call void @llvm.trap() #2, !nosanitize !{}
unreachable, !nosanitize !{}

cont: ; preds = %for.body
%2 = extractvalue { i32, i1 } %0, 0
%cmp = icmp sle i32 %2, 2147483647
br i1 %cmp, label %for.body, label %for.cond.cleanup
}

define void @f_uadd(ptr %a) {
; CHECK-LABEL: @f_uadd(
; CHECK-LABEL: define void @f_uadd(
; CHECK-SAME: ptr [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: br label %[[FOR_BODY:.*]]
; CHECK: [[FOR_COND_CLEANUP:.*]]:
; CHECK-NEXT: ret void
; CHECK: [[FOR_BODY]]:
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], %[[CONT:.*]] ], [ 0, %[[ENTRY]] ]
; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 [[INDVARS_IV]]
; CHECK-NEXT: store i8 0, ptr [[ARRAYIDX]], align 1
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nuw nsw i64 [[INDVARS_IV]], 1
; CHECK-NEXT: br i1 false, label %[[TRAP:.*]], label %[[CONT]], !nosanitize [[META0]]
; CHECK: [[TRAP]]:
; CHECK-NEXT: tail call void @llvm.trap(), !nosanitize [[META0]]
; CHECK-NEXT: unreachable, !nosanitize [[META0]]
; CHECK: [[CONT]]:
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i64 [[INDVARS_IV_NEXT]], 16
; CHECK-NEXT: br i1 [[EXITCOND]], label %[[FOR_BODY]], label %[[FOR_COND_CLEANUP]]
;
entry:
br label %for.body

Expand All @@ -48,9 +127,6 @@ for.body: ; preds = %entry, %cont
store i8 0, ptr %arrayidx, align 1
%0 = tail call { i32, i1 } @llvm.uadd.with.overflow.i32(i32 %i.04, i32 1)
%1 = extractvalue { i32, i1 } %0, 1
; CHECK: for.body:
; CHECK-NOT: @llvm.uadd.with.overflow
; CHECK: br i1 false, label %trap, label %cont, !nosanitize !0
br i1 %1, label %trap, label %cont, !nosanitize !{}

trap: ; preds = %for.body
Expand All @@ -63,8 +139,71 @@ cont: ; preds = %for.body
br i1 %cmp, label %for.body, label %for.cond.cleanup
}

define void @f_uadd_overflow(ptr %a) {
; CHECK-LABEL: define void @f_uadd_overflow(
; CHECK-SAME: ptr [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: br label %[[FOR_BODY:.*]]
; CHECK: [[FOR_COND_CLEANUP:.*]]:
; CHECK-NEXT: ret void
; CHECK: [[FOR_BODY]]:
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], %[[CONT:.*]] ], [ -6, %[[ENTRY]] ]
; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 [[INDVARS_IV]]
; CHECK-NEXT: store i8 0, ptr [[ARRAYIDX]], align 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp eq i64 [[INDVARS_IV]], -1
; CHECK-NEXT: br i1 [[EXITCOND]], label %[[TRAP:.*]], label %[[CONT]], !nosanitize [[META0]]
; CHECK: [[TRAP]]:
; CHECK-NEXT: tail call void @llvm.trap(), !nosanitize [[META0]]
; CHECK-NEXT: unreachable, !nosanitize [[META0]]
; CHECK: [[CONT]]:
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nsw i64 [[INDVARS_IV]], 1
; CHECK-NEXT: br i1 true, label %[[FOR_BODY]], label %[[FOR_COND_CLEANUP]]
;
entry:
br label %for.body

for.cond.cleanup: ; preds = %cont
ret void

for.body: ; preds = %entry, %cont
%i.04 = phi i32 [ 4294967290, %entry ], [ %2, %cont ]
%idxprom = sext i32 %i.04 to i64
%arrayidx = getelementptr inbounds i8, ptr %a, i64 %idxprom
store i8 0, ptr %arrayidx, align 1
%0 = tail call { i32, i1 } @llvm.uadd.with.overflow.i32(i32 %i.04, i32 1)
%1 = extractvalue { i32, i1 } %0, 1
br i1 %1, label %trap, label %cont, !nosanitize !{}

trap: ; preds = %for.body
tail call void @llvm.trap(), !nosanitize !{}
unreachable, !nosanitize !{}

cont: ; preds = %for.body
%2 = extractvalue { i32, i1 } %0, 0
%cmp = icmp ule i32 %2, 4294967295
br i1 %cmp, label %for.body, label %for.cond.cleanup
}

define void @f_ssub(ptr nocapture %a) {
; CHECK-LABEL: @f_ssub(
; CHECK-LABEL: define void @f_ssub(
; CHECK-SAME: ptr captures(none) [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: br label %[[FOR_BODY:.*]]
; CHECK: [[FOR_COND_CLEANUP:.*]]:
; CHECK-NEXT: ret void
; CHECK: [[FOR_BODY]]:
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], %[[CONT:.*]] ], [ 15, %[[ENTRY]] ]
; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 [[INDVARS_IV]]
; CHECK-NEXT: store i8 0, ptr [[ARRAYIDX]], align 1
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nsw i64 [[INDVARS_IV]], -1
; CHECK-NEXT: br i1 false, label %[[TRAP:.*]], label %[[CONT]], !nosanitize [[META0]]
; CHECK: [[TRAP]]:
; CHECK-NEXT: tail call void @llvm.trap(), !nosanitize [[META0]]
; CHECK-NEXT: unreachable, !nosanitize [[META0]]
; CHECK: [[CONT]]:
; CHECK-NEXT: [[CMP:%.*]] = icmp sgt i64 [[INDVARS_IV_NEXT]], -1
; CHECK-NEXT: br i1 [[CMP]], label %[[FOR_BODY]], label %[[FOR_COND_CLEANUP]]
;
entry:
br label %for.body

Expand All @@ -78,9 +217,6 @@ for.body: ; preds = %entry, %cont
store i8 0, ptr %arrayidx, align 1
%0 = tail call { i32, i1 } @llvm.ssub.with.overflow.i32(i32 %i.04, i32 1)
%1 = extractvalue { i32, i1 } %0, 1
; CHECK: for.body:
; CHECK-NOT: @llvm.ssub.with.overflow.i32
; CHECK: br i1 false, label %trap, label %cont, !nosanitize !0
br i1 %1, label %trap, label %cont, !nosanitize !{}

trap: ; preds = %for.body
Expand All @@ -93,8 +229,76 @@ cont: ; preds = %for.body
br i1 %cmp, label %for.body, label %for.cond.cleanup
}

; It is theoretically possible to replace the `ssub.with.overflow` with a
; condition on the IV, but SCEV cannot represent non-unsigned-wrapping
; subtraction operations.
define void @f_ssub_overflow(ptr nocapture %a) {
; CHECK-LABEL: define void @f_ssub_overflow(
; CHECK-SAME: ptr captures(none) [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: br label %[[FOR_BODY:.*]]
; CHECK: [[FOR_COND_CLEANUP:.*]]:
; CHECK-NEXT: ret void
; CHECK: [[FOR_BODY]]:
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], %[[CONT:.*]] ], [ -2147483642, %[[ENTRY]] ]
; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 [[INDVARS_IV]]
; CHECK-NEXT: store i8 0, ptr [[ARRAYIDX]], align 1
; CHECK-NEXT: [[TMP0:%.*]] = trunc nsw i64 [[INDVARS_IV]] to i32
; CHECK-NEXT: [[TMP1:%.*]] = tail call { i32, i1 } @llvm.ssub.with.overflow.i32(i32 [[TMP0]], i32 1)
; CHECK-NEXT: [[TMP2:%.*]] = extractvalue { i32, i1 } [[TMP1]], 1
; CHECK-NEXT: br i1 [[TMP2]], label %[[TRAP:.*]], label %[[CONT]], !nosanitize [[META0]]
; CHECK: [[TRAP]]:
; CHECK-NEXT: tail call void @llvm.trap(), !nosanitize [[META0]]
; CHECK-NEXT: unreachable, !nosanitize [[META0]]
; CHECK: [[CONT]]:
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nsw i64 [[INDVARS_IV]], -1
; CHECK-NEXT: br i1 true, label %[[FOR_BODY]], label %[[FOR_COND_CLEANUP]]
;
entry:
br label %for.body

for.cond.cleanup: ; preds = %cont
ret void

for.body: ; preds = %entry, %cont
%i.04 = phi i32 [ -2147483642, %entry ], [ %2, %cont ]
%idxprom = sext i32 %i.04 to i64
%arrayidx = getelementptr inbounds i8, ptr %a, i64 %idxprom
store i8 0, ptr %arrayidx, align 1
%0 = tail call { i32, i1 } @llvm.ssub.with.overflow.i32(i32 %i.04, i32 1)
%1 = extractvalue { i32, i1 } %0, 1
br i1 %1, label %trap, label %cont, !nosanitize !{}

trap: ; preds = %for.body
tail call void @llvm.trap(), !nosanitize !{}
unreachable, !nosanitize !{}

cont: ; preds = %for.body
%2 = extractvalue { i32, i1 } %0, 0
%cmp = icmp sge i32 %2, -2147483648
br i1 %cmp, label %for.body, label %for.cond.cleanup
}

define void @f_usub(ptr nocapture %a) {
; CHECK-LABEL: @f_usub(
; CHECK-LABEL: define void @f_usub(
; CHECK-SAME: ptr captures(none) [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: br label %[[FOR_BODY:.*]]
; CHECK: [[FOR_COND_CLEANUP:.*]]:
; CHECK-NEXT: ret void
; CHECK: [[FOR_BODY]]:
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], %[[CONT:.*]] ], [ 15, %[[ENTRY]] ]
; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 [[INDVARS_IV]]
; CHECK-NEXT: store i8 0, ptr [[ARRAYIDX]], align 1
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nsw i64 [[INDVARS_IV]], -1
; CHECK-NEXT: br i1 false, label %[[TRAP:.*]], label %[[CONT]], !nosanitize [[META0]]
; CHECK: [[TRAP]]:
; CHECK-NEXT: tail call void @llvm.trap(), !nosanitize [[META0]]
; CHECK-NEXT: unreachable, !nosanitize [[META0]]
; CHECK: [[CONT]]:
; CHECK-NEXT: [[CMP:%.*]] = icmp samesign ugt i64 [[INDVARS_IV_NEXT]], 0
; CHECK-NEXT: br i1 [[CMP]], label %[[FOR_BODY]], label %[[FOR_COND_CLEANUP]]
;
entry:
br label %for.body

Expand All @@ -109,9 +313,6 @@ for.body: ; preds = %entry, %cont
%0 = tail call { i32, i1 } @llvm.usub.with.overflow.i32(i32 %i.04, i32 1)
%1 = extractvalue { i32, i1 } %0, 1

; CHECK: for.body:
; CHECK-NOT: @llvm.usub.with.overflow.i32
; CHECK: br i1 false, label %trap, label %cont, !nosanitize !0
br i1 %1, label %trap, label %cont, !nosanitize !{}

trap: ; preds = %for.body
Expand All @@ -124,8 +325,31 @@ cont: ; preds = %for.body
br i1 %cmp, label %for.body, label %for.cond.cleanup
}

; It is theoretically possible to replace the `usub.with.overflow` with a
; condition on the IV, but SCEV cannot represent non-unsigned-wrapping
; subtraction operations.
define void @f_usub_overflow(ptr nocapture %a) {
; CHECK-LABEL: @f_usub_overflow(
; CHECK-LABEL: define void @f_usub_overflow(
; CHECK-SAME: ptr captures(none) [[A:%.*]]) {
; CHECK-NEXT: [[ENTRY:.*]]:
; CHECK-NEXT: br label %[[FOR_BODY:.*]]
; CHECK: [[FOR_COND_CLEANUP:.*]]:
; CHECK-NEXT: ret void
; CHECK: [[FOR_BODY]]:
; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], %[[CONT:.*]] ], [ 15, %[[ENTRY]] ]
; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 [[INDVARS_IV]]
; CHECK-NEXT: store i8 0, ptr [[ARRAYIDX]], align 1
; CHECK-NEXT: [[TMP0:%.*]] = trunc nuw nsw i64 [[INDVARS_IV]] to i32
; CHECK-NEXT: [[TMP1:%.*]] = tail call { i32, i1 } @llvm.usub.with.overflow.i32(i32 [[TMP0]], i32 1)
; CHECK-NEXT: [[TMP2:%.*]] = extractvalue { i32, i1 } [[TMP1]], 1
; CHECK-NEXT: br i1 [[TMP2]], label %[[TRAP:.*]], label %[[CONT]], !nosanitize [[META0]]
; CHECK: [[TRAP]]:
; CHECK-NEXT: tail call void @llvm.trap(), !nosanitize [[META0]]
; CHECK-NEXT: unreachable, !nosanitize [[META0]]
; CHECK: [[CONT]]:
; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nsw i64 [[INDVARS_IV]], -1
; CHECK-NEXT: br i1 true, label %[[FOR_BODY]], label %[[FOR_COND_CLEANUP]]
;
entry:
br label %for.body

Expand All @@ -139,13 +363,6 @@ for.body: ; preds = %entry, %cont
store i8 0, ptr %arrayidx, align 1
%0 = tail call { i32, i1 } @llvm.usub.with.overflow.i32(i32 %i.04, i32 1)
%1 = extractvalue { i32, i1 } %0, 1

; It is theoretically possible to prove this, but SCEV cannot
; represent non-unsigned-wrapping subtraction operations.

; CHECK: for.body:
; CHECK: [[COND:%[^ ]+]] = extractvalue { i32, i1 } %1, 1
; CHECK-NEXT: br i1 [[COND]], label %trap, label %cont, !nosanitize !0
br i1 %1, label %trap, label %cont, !nosanitize !{}

trap: ; preds = %for.body
Expand All @@ -166,3 +383,6 @@ declare { i32, i1 } @llvm.smul.with.overflow.i32(i32, i32) nounwind readnone
declare { i32, i1 } @llvm.umul.with.overflow.i32(i32, i32) nounwind readnone

declare void @llvm.trap() #2
;.
; CHECK: [[META0]] = !{}
;.