1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py 2; RUN: opt -S -passes=indvars < %s | FileCheck %s 3 4target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128-ni:1-p2:32:8:8:32-ni:2" 5target triple = "x86_64-unknown-linux-gnu" 6 7; Make sure we don't branch by poison here. 8define void @test(i32 %start) { 9; CHECK-LABEL: @test( 10; CHECK-NEXT: entry: 11; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[START:%.*]], -1 12; CHECK-NEXT: [[TMP1:%.*]] = zext i32 [[START]] to i64 13; CHECK-NEXT: br label [[LOOP:%.*]] 14; CHECK: backedge: 15; CHECK-NEXT: br label [[LOOP]] 16; CHECK: loop: 17; CHECK-NEXT: [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], [[BACKEDGE:%.*]] ], [ [[TMP1]], [[ENTRY:%.*]] ] 18; CHECK-NEXT: [[INDVARS_IV_NEXT]] = add nsw i64 [[INDVARS_IV]], -1 19; CHECK-NEXT: [[INDVARS:%.*]] = trunc i64 [[INDVARS_IV_NEXT]] to i32 20; CHECK-NEXT: [[LOOP_EXIT_COND:%.*]] = icmp slt i32 [[TMP0]], 11 21; CHECK-NEXT: br i1 [[LOOP_EXIT_COND]], label [[EXIT:%.*]], label [[STUCK_PREHEADER:%.*]] 22; CHECK: stuck.preheader: 23; CHECK-NEXT: br label [[STUCK:%.*]] 24; CHECK: exit: 25; CHECK-NEXT: [[IV_NEXT_LCSSA:%.*]] = phi i32 [ [[INDVARS]], [[LOOP]] ] 26; CHECK-NEXT: ret void 27; CHECK: stuck: 28; CHECK-NEXT: br i1 false, label [[BACKEDGE]], label [[STUCK]] 29; 30entry: 31 br label %loop 32 33backedge: ; preds = %stuck 34 br label %loop 35 36loop: ; preds = %backedge, %entry 37 %iv = phi i32 [ %start, %entry ], [ %iv.next, %backedge ] 38 %iv.zext = zext i32 %iv to i64 39 %gep = getelementptr inbounds i64, ptr undef, i64 %iv.zext 40 %iv.next = add i32 %iv, -1 41 %loop.exit.cond = icmp slt i32 %iv.next, 11 42 br i1 %loop.exit.cond, label %exit, label %stuck 43 44exit: ; preds = %loop 45 %iv.next.lcssa = phi i32 [ %iv.next, %loop ] 46 ret void 47 48stuck: ; preds = %stuck, %loop 49 br i1 false, label %backedge, label %stuck 50} 51