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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes=indvars,guard-widening -S < %s | FileCheck %s
declare i32 @llvm.experimental.deoptimize.i32(...)
; Make sure that guard widening does not turn loop-invariant condition
; (that then gets optimized basing on this fact) into non-invariant.
; https://github.com/llvm/llvm-project/issues/60234 explains how it causes
; a miscompile.
define i32 @test(i32 %start) {
; CHECK-LABEL: @test(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[WC1:%.*]] = call i1 @llvm.experimental.widenable.condition()
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: br i1 [[WC1]], label [[GUARD_BLOCK:%.*]], label [[EXIT_BY_WC:%.*]]
; CHECK: exit_by_wc:
; CHECK-NEXT: [[IV_LCSSA:%.*]] = phi i32 [ [[START]], [[LOOP]] ]
; CHECK-NEXT: [[RVAL1:%.*]] = call i32 (...) @llvm.experimental.deoptimize.i32() [ "deopt"(i32 [[IV_LCSSA]]) ]
; CHECK-NEXT: ret i32 [[RVAL1]]
; CHECK: guard_block:
; CHECK-NEXT: [[START_PLUS_1:%.*]] = add i32 [[START]], 1
; CHECK-NEXT: [[COND:%.*]] = icmp ne i32 [[START_PLUS_1]], [[IV]]
; CHECK-NEXT: [[WC2:%.*]] = call i1 @llvm.experimental.widenable.condition()
; CHECK-NEXT: [[GUARD:%.*]] = and i1 [[COND]], [[WC2]]
; CHECK-NEXT: br i1 [[GUARD]], label [[BACKEDGE]], label [[FAILURE:%.*]]
; CHECK: backedge:
; CHECK-NEXT: call void @side_effect()
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: br label [[LOOP]]
; CHECK: exit:
; CHECK-NEXT: ret i32 -1
; CHECK: failure:
; CHECK-NEXT: [[IV_LCSSA1:%.*]] = phi i32 [ [[IV]], [[GUARD_BLOCK]] ]
; CHECK-NEXT: [[RVAL2:%.*]] = call i32 (...) @llvm.experimental.deoptimize.i32() [ "deopt"(i32 [[IV_LCSSA1]]) ]
; CHECK-NEXT: ret i32 [[RVAL2]]
;
entry:
%wc1 = call i1 @llvm.experimental.widenable.condition()
br label %loop
loop:
%iv = phi i32 [ %start, %entry ], [ %iv.next, %backedge ]
br i1 %wc1, label %guard_block, label %exit_by_wc
exit_by_wc:
%rval1 = call i32(...) @llvm.experimental.deoptimize.i32() [ "deopt"(i32 %iv) ]
ret i32 %rval1
guard_block:
%start_plus_1 = add i32 %start, 1
%cond = icmp ne i32 %start_plus_1, %iv
%wc2 = call i1 @llvm.experimental.widenable.condition()
%guard = and i1 %cond, %wc2
br i1 %guard, label %backedge, label %failure
backedge:
call void @side_effect()
%iv.next = add i32 %iv, 1
br label %loop
exit:
ret i32 -1
failure:
%rval2 = call i32(...) @llvm.experimental.deoptimize.i32() [ "deopt"(i32 %iv) ]
ret i32 %rval2
}
; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(inaccessiblemem: readwrite)
declare i1 @llvm.experimental.widenable.condition()
declare void @side_effect()
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