; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -indvars -indvars-predicate-loops=1 -S | FileCheck %s declare void @prevent_merging() ; Base case define i32 @test1(i32* %array, i32 %length, i32 %n) { ; CHECK-LABEL: @test1( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: [[TMP0:%.*]] = icmp ugt i32 [[N:%.*]], 1 ; CHECK-NEXT: [[UMAX:%.*]] = select i1 [[TMP0]], i32 [[N]], i32 1 ; CHECK-NEXT: [[TMP1:%.*]] = add i32 [[UMAX]], -1 ; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i32 [[LENGTH:%.*]], [[TMP1]] ; CHECK-NEXT: [[UMIN:%.*]] = select i1 [[TMP2]], i32 [[LENGTH]], i32 [[TMP1]] ; CHECK-NEXT: [[TMP3:%.*]] = icmp ne i32 [[LENGTH]], [[UMIN]] ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ] ; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: br i1 [[TMP3]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64 ; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]] ; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1 ; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N]] ; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ] ; CHECK-NEXT: ret i32 [[RESULT]] ; loop.preheader: ; preds = %entry br label %loop loop: ; preds = %guarded, %loop.preheader %loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ] %i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ] %within.bounds = icmp ult i32 %i, %length br i1 %within.bounds, label %guarded, label %deopt, !prof !0 deopt: ; preds = %loop call void @prevent_merging() ret i32 -1 guarded: ; preds = %loop %i.i64 = zext i32 %i to i64 %array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i.i64 %array.i = load i32, i32* %array.i.ptr, align 4 %loop.acc.next = add i32 %loop.acc, %array.i %i.next = add nuw i32 %i, 1 %continue = icmp ult i32 %i.next, %n br i1 %continue, label %loop, label %exit exit: ; preds = %guarded, %entry %result = phi i32 [ %loop.acc.next, %guarded ] ret i32 %result } ; Has side effect which must be reflected define i32 @neg_store(i32* %array, i32 %length, i32 %n) { ; CHECK-LABEL: @neg_store( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ] ; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: [[WITHIN_BOUNDS:%.*]] = icmp ult i32 [[I]], [[LENGTH:%.*]] ; CHECK-NEXT: br i1 [[WITHIN_BOUNDS]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64 ; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]] ; CHECK-NEXT: store i32 0, i32* [[ARRAY_I_PTR]] ; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1 ; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N:%.*]] ; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ] ; CHECK-NEXT: ret i32 [[RESULT]] ; loop.preheader: ; preds = %entry br label %loop loop: ; preds = %guarded, %loop.preheader %loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ] %i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ] %within.bounds = icmp ult i32 %i, %length br i1 %within.bounds, label %guarded, label %deopt, !prof !0 deopt: ; preds = %loop call void @prevent_merging() ret i32 -1 guarded: ; preds = %loop %i.i64 = zext i32 %i to i64 %array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i.i64 %array.i = load i32, i32* %array.i.ptr, align 4 %loop.acc.next = add i32 %loop.acc, %array.i store i32 0, i32* %array.i.ptr %i.next = add nuw i32 %i, 1 %continue = icmp ult i32 %i.next, %n br i1 %continue, label %loop, label %exit exit: ; preds = %guarded, %entry %result = phi i32 [ %loop.acc.next, %guarded ] ret i32 %result } declare void @maythrow() ; May exit through implicit exception edge define i32 @neg_implicit_exit(i32* %array, i32 %length, i32 %n) { ; CHECK-LABEL: @neg_implicit_exit( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ] ; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: call void @maythrow() ; CHECK-NEXT: [[WITHIN_BOUNDS:%.*]] = icmp ult i32 [[I]], [[LENGTH:%.*]] ; CHECK-NEXT: br i1 [[WITHIN_BOUNDS]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64 ; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]] ; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1 ; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N:%.*]] ; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ] ; CHECK-NEXT: ret i32 [[RESULT]] ; loop.preheader: ; preds = %entry br label %loop loop: ; preds = %guarded, %loop.preheader %loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ] %i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ] call void @maythrow() %within.bounds = icmp ult i32 %i, %length br i1 %within.bounds, label %guarded, label %deopt, !prof !0 deopt: ; preds = %loop call void @prevent_merging() ret i32 -1 guarded: ; preds = %loop %i.i64 = zext i32 %i to i64 %array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i.i64 %array.i = load i32, i32* %array.i.ptr, align 4 %loop.acc.next = add i32 %loop.acc, %array.i %i.next = add nuw i32 %i, 1 %continue = icmp ult i32 %i.next, %n br i1 %continue, label %loop, label %exit exit: ; preds = %guarded, %entry %result = phi i32 [ %loop.acc.next, %guarded ] ret i32 %result } ; Base case, but in LFTR form (just for sanity checking) define i32 @test2(i32* %array, i32 %length, i32 %n) { ; CHECK-LABEL: @test2( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[N:%.*]], -1 ; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i32 [[LENGTH:%.*]], [[TMP0]] ; CHECK-NEXT: [[UMIN:%.*]] = select i1 [[TMP1]], i32 [[LENGTH]], i32 [[TMP0]] ; CHECK-NEXT: [[TMP2:%.*]] = icmp ne i32 [[LENGTH]], [[UMIN]] ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ] ; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: br i1 [[TMP2]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64 ; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]] ; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1 ; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ne i32 [[I_NEXT]], [[N]] ; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ] ; CHECK-NEXT: ret i32 [[RESULT]] ; loop.preheader: ; preds = %entry br label %loop loop: ; preds = %guarded, %loop.preheader %loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ] %i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ] %within.bounds = icmp ne i32 %i, %length br i1 %within.bounds, label %guarded, label %deopt, !prof !0 deopt: ; preds = %loop call void @prevent_merging() ret i32 -1 guarded: ; preds = %loop %i.i64 = zext i32 %i to i64 %array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i.i64 %array.i = load i32, i32* %array.i.ptr, align 4 %loop.acc.next = add i32 %loop.acc, %array.i %i.next = add nuw i32 %i, 1 %continue = icmp ne i32 %i.next, %n br i1 %continue, label %loop, label %exit exit: ; preds = %guarded, %entry %result = phi i32 [ %loop.acc.next, %guarded ] ret i32 %result } ; br (and rcheck1, rcheck2) define i32 @two_range_checks(i32* %array.1, i32 %length.1, i32* %array.2, i32 %length.2, i32 %n) { ; CHECK-LABEL: @two_range_checks( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[LENGTH_2:%.*]], [[LENGTH_1:%.*]] ; CHECK-NEXT: [[UMIN:%.*]] = select i1 [[TMP0]], i32 [[LENGTH_2]], i32 [[LENGTH_1]] ; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i32 [[LENGTH_2]], [[LENGTH_1]] ; CHECK-NEXT: [[UMIN1:%.*]] = select i1 [[TMP1]], i32 [[LENGTH_2]], i32 [[LENGTH_1]] ; CHECK-NEXT: [[TMP2:%.*]] = icmp ugt i32 [[N:%.*]], 1 ; CHECK-NEXT: [[UMAX:%.*]] = select i1 [[TMP2]], i32 [[N]], i32 1 ; CHECK-NEXT: [[TMP3:%.*]] = add i32 [[UMAX]], -1 ; CHECK-NEXT: [[TMP4:%.*]] = icmp ult i32 [[UMIN1]], [[TMP3]] ; CHECK-NEXT: [[UMIN2:%.*]] = select i1 [[TMP4]], i32 [[UMIN1]], i32 [[TMP3]] ; CHECK-NEXT: [[TMP5:%.*]] = icmp ne i32 [[UMIN]], [[UMIN2]] ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ] ; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: br i1 [[TMP5]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64 ; CHECK-NEXT: [[ARRAY_1_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_1:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_1_I:%.*]] = load i32, i32* [[ARRAY_1_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_1:%.*]] = add i32 [[LOOP_ACC]], [[ARRAY_1_I]] ; CHECK-NEXT: [[ARRAY_2_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_2:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_2_I:%.*]] = load i32, i32* [[ARRAY_2_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC_1]], [[ARRAY_2_I]] ; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1 ; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N]] ; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ] ; CHECK-NEXT: ret i32 [[RESULT]] ; loop.preheader: ; preds = %entry br label %loop loop: ; preds = %guarded, %loop.preheader %loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ] %i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ] %within.bounds.1 = icmp ult i32 %i, %length.1 %within.bounds.2 = icmp ult i32 %i, %length.2 %within.bounds = and i1 %within.bounds.1, %within.bounds.2 br i1 %within.bounds, label %guarded, label %deopt, !prof !0 deopt: ; preds = %loop call void @prevent_merging() ret i32 -1 guarded: ; preds = %loop %i.i64 = zext i32 %i to i64 %array.1.i.ptr = getelementptr inbounds i32, i32* %array.1, i64 %i.i64 %array.1.i = load i32, i32* %array.1.i.ptr, align 4 %loop.acc.1 = add i32 %loop.acc, %array.1.i %array.2.i.ptr = getelementptr inbounds i32, i32* %array.2, i64 %i.i64 %array.2.i = load i32, i32* %array.2.i.ptr, align 4 %loop.acc.next = add i32 %loop.acc.1, %array.2.i %i.next = add nuw i32 %i, 1 %continue = icmp ult i32 %i.next, %n br i1 %continue, label %loop, label %exit exit: ; preds = %guarded, %entry %result = phi i32 [ %loop.acc.next, %guarded ] ret i32 %result } define i32 @three_range_checks(i32* %array.1, i32 %length.1, i32* %array.2, i32 %length.2, i32* %array.3, i32 %length.3, i32 %n) { ; CHECK-LABEL: @three_range_checks( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[LENGTH_3:%.*]], [[LENGTH_2:%.*]] ; CHECK-NEXT: [[UMIN:%.*]] = select i1 [[TMP0]], i32 [[LENGTH_3]], i32 [[LENGTH_2]] ; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i32 [[UMIN]], [[LENGTH_1:%.*]] ; CHECK-NEXT: [[UMIN1:%.*]] = select i1 [[TMP1]], i32 [[UMIN]], i32 [[LENGTH_1]] ; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i32 [[LENGTH_3]], [[LENGTH_2]] ; CHECK-NEXT: [[UMIN2:%.*]] = select i1 [[TMP2]], i32 [[LENGTH_3]], i32 [[LENGTH_2]] ; CHECK-NEXT: [[TMP3:%.*]] = icmp ult i32 [[UMIN2]], [[LENGTH_1]] ; CHECK-NEXT: [[UMIN3:%.*]] = select i1 [[TMP3]], i32 [[UMIN2]], i32 [[LENGTH_1]] ; CHECK-NEXT: [[TMP4:%.*]] = icmp ugt i32 [[N:%.*]], 1 ; CHECK-NEXT: [[UMAX:%.*]] = select i1 [[TMP4]], i32 [[N]], i32 1 ; CHECK-NEXT: [[TMP5:%.*]] = add i32 [[UMAX]], -1 ; CHECK-NEXT: [[TMP6:%.*]] = icmp ult i32 [[UMIN3]], [[TMP5]] ; CHECK-NEXT: [[UMIN4:%.*]] = select i1 [[TMP6]], i32 [[UMIN3]], i32 [[TMP5]] ; CHECK-NEXT: [[TMP7:%.*]] = icmp ne i32 [[UMIN1]], [[UMIN4]] ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ] ; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: br i1 [[TMP7]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64 ; CHECK-NEXT: [[ARRAY_1_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_1:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_1_I:%.*]] = load i32, i32* [[ARRAY_1_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_1:%.*]] = add i32 [[LOOP_ACC]], [[ARRAY_1_I]] ; CHECK-NEXT: [[ARRAY_2_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_2:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_2_I:%.*]] = load i32, i32* [[ARRAY_2_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_2:%.*]] = add i32 [[LOOP_ACC_1]], [[ARRAY_2_I]] ; CHECK-NEXT: [[ARRAY_3_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_3:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_3_I:%.*]] = load i32, i32* [[ARRAY_3_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC_2]], [[ARRAY_3_I]] ; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1 ; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N]] ; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ] ; CHECK-NEXT: ret i32 [[RESULT]] ; loop.preheader: ; preds = %entry br label %loop loop: ; preds = %guarded, %loop.preheader %loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ] %i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ] %within.bounds.1 = icmp ult i32 %i, %length.1 %within.bounds.2 = icmp ult i32 %i, %length.2 %within.bounds.3 = icmp ult i32 %i, %length.3 %within.bounds.1.and.2 = and i1 %within.bounds.1, %within.bounds.2 %within.bounds = and i1 %within.bounds.1.and.2, %within.bounds.3 br i1 %within.bounds, label %guarded, label %deopt, !prof !0 deopt: ; preds = %loop call void @prevent_merging() ret i32 -1 guarded: ; preds = %loop %i.i64 = zext i32 %i to i64 %array.1.i.ptr = getelementptr inbounds i32, i32* %array.1, i64 %i.i64 %array.1.i = load i32, i32* %array.1.i.ptr, align 4 %loop.acc.1 = add i32 %loop.acc, %array.1.i %array.2.i.ptr = getelementptr inbounds i32, i32* %array.2, i64 %i.i64 %array.2.i = load i32, i32* %array.2.i.ptr, align 4 %loop.acc.2 = add i32 %loop.acc.1, %array.2.i %array.3.i.ptr = getelementptr inbounds i32, i32* %array.3, i64 %i.i64 %array.3.i = load i32, i32* %array.3.i.ptr, align 4 %loop.acc.next = add i32 %loop.acc.2, %array.3.i %i.next = add nuw i32 %i, 1 %continue = icmp ult i32 %i.next, %n br i1 %continue, label %loop, label %exit exit: ; preds = %guarded, %entry %result = phi i32 [ %loop.acc.next, %guarded ] ret i32 %result } ; Analogous to the above, but with two distinct branches (on different conditions) define i32 @distinct_checks(i32* %array.1, i32 %length.1, i32* %array.2, i32 %length.2, i32* %array.3, i32 %length.3, i32 %n) { ; CHECK-LABEL: @distinct_checks( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i32 [[LENGTH_2:%.*]], [[LENGTH_1:%.*]] ; CHECK-NEXT: [[UMIN:%.*]] = select i1 [[TMP0]], i32 [[LENGTH_2]], i32 [[LENGTH_1]] ; CHECK-NEXT: [[TMP1:%.*]] = icmp ugt i32 [[N:%.*]], 1 ; CHECK-NEXT: [[UMAX:%.*]] = select i1 [[TMP1]], i32 [[N]], i32 1 ; CHECK-NEXT: [[TMP2:%.*]] = add i32 [[UMAX]], -1 ; CHECK-NEXT: [[TMP3:%.*]] = icmp ult i32 [[UMIN]], [[TMP2]] ; CHECK-NEXT: [[UMIN1:%.*]] = select i1 [[TMP3]], i32 [[UMIN]], i32 [[TMP2]] ; CHECK-NEXT: [[TMP4:%.*]] = icmp ne i32 [[LENGTH_1]], [[UMIN1]] ; CHECK-NEXT: [[TMP5:%.*]] = icmp ne i32 [[LENGTH_2]], [[UMIN1]] ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED1:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ] ; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED1]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: br i1 [[TMP4]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64 ; CHECK-NEXT: [[ARRAY_1_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_1:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_1_I:%.*]] = load i32, i32* [[ARRAY_1_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_1:%.*]] = add i32 [[LOOP_ACC]], [[ARRAY_1_I]] ; CHECK-NEXT: br i1 [[TMP5]], label [[GUARDED1]], label [[DEOPT2:%.*]], !prof !0 ; CHECK: deopt2: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded1: ; CHECK-NEXT: [[ARRAY_3_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_3:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_3_I:%.*]] = load i32, i32* [[ARRAY_3_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC_1]], [[ARRAY_3_I]] ; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1 ; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N]] ; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED1]] ] ; CHECK-NEXT: ret i32 [[RESULT]] ; loop.preheader: ; preds = %entry br label %loop loop: ; preds = %guarded4, %loop.preheader %loop.acc = phi i32 [ %loop.acc.next, %guarded1 ], [ 0, %loop.preheader ] %i = phi i32 [ %i.next, %guarded1 ], [ 0, %loop.preheader ] %within.bounds.1 = icmp ult i32 %i, %length.1 br i1 %within.bounds.1, label %guarded, label %deopt, !prof !0 deopt: ; preds = %loop call void @prevent_merging() ret i32 -1 guarded: ; preds = %loop %i.i64 = zext i32 %i to i64 %array.1.i.ptr = getelementptr inbounds i32, i32* %array.1, i64 %i.i64 %array.1.i = load i32, i32* %array.1.i.ptr, align 4 %loop.acc.1 = add i32 %loop.acc, %array.1.i %within.bounds.2 = icmp ult i32 %i, %length.2 br i1 %within.bounds.2, label %guarded1, label %deopt2, !prof !0 deopt2: ; preds = %guarded call void @prevent_merging() ret i32 -1 guarded1: ; preds = %guarded1 %array.3.i.ptr = getelementptr inbounds i32, i32* %array.3, i64 %i.i64 %array.3.i = load i32, i32* %array.3.i.ptr, align 4 %loop.acc.next = add i32 %loop.acc.1, %array.3.i %i.next = add nuw i32 %i, 1 %continue = icmp ult i32 %i.next, %n br i1 %continue, label %loop, label %exit exit: %result = phi i32 [ %loop.acc.next, %guarded1 ] ret i32 %result } define i32 @duplicate_checks(i32* %array.1, i32* %array.2, i32* %array.3, i32 %length, i32 %n) { ; CHECK-LABEL: @duplicate_checks( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: [[TMP0:%.*]] = icmp ugt i32 [[N:%.*]], 1 ; CHECK-NEXT: [[UMAX:%.*]] = select i1 [[TMP0]], i32 [[N]], i32 1 ; CHECK-NEXT: [[TMP1:%.*]] = add i32 [[UMAX]], -1 ; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i32 [[LENGTH:%.*]], [[TMP1]] ; CHECK-NEXT: [[UMIN:%.*]] = select i1 [[TMP2]], i32 [[LENGTH]], i32 [[TMP1]] ; CHECK-NEXT: [[TMP3:%.*]] = icmp ne i32 [[LENGTH]], [[UMIN]] ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED1:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ] ; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED1]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: br i1 [[TMP3]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64 ; CHECK-NEXT: [[ARRAY_1_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_1:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_1_I:%.*]] = load i32, i32* [[ARRAY_1_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_1:%.*]] = add i32 [[LOOP_ACC]], [[ARRAY_1_I]] ; CHECK-NEXT: br i1 true, label [[GUARDED1]], label [[DEOPT2:%.*]], !prof !0 ; CHECK: deopt2: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded1: ; CHECK-NEXT: [[ARRAY_3_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY_3:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_3_I:%.*]] = load i32, i32* [[ARRAY_3_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC_1]], [[ARRAY_3_I]] ; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1 ; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N]] ; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED1]] ] ; CHECK-NEXT: ret i32 [[RESULT]] ; loop.preheader: ; preds = %entry br label %loop loop: ; preds = %guarded4, %loop.preheader %loop.acc = phi i32 [ %loop.acc.next, %guarded1 ], [ 0, %loop.preheader ] %i = phi i32 [ %i.next, %guarded1 ], [ 0, %loop.preheader ] %within.bounds.1 = icmp ult i32 %i, %length br i1 %within.bounds.1, label %guarded, label %deopt, !prof !0 deopt: ; preds = %loop call void @prevent_merging() ret i32 -1 guarded: ; preds = %loop %i.i64 = zext i32 %i to i64 %array.1.i.ptr = getelementptr inbounds i32, i32* %array.1, i64 %i.i64 %array.1.i = load i32, i32* %array.1.i.ptr, align 4 %loop.acc.1 = add i32 %loop.acc, %array.1.i %within.bounds.2 = icmp ult i32 %i, %length br i1 %within.bounds.2, label %guarded1, label %deopt2, !prof !0 deopt2: ; preds = %guarded call void @prevent_merging() ret i32 -1 guarded1: ; preds = %guarded1 %array.3.i.ptr = getelementptr inbounds i32, i32* %array.3, i64 %i.i64 %array.3.i = load i32, i32* %array.3.i.ptr, align 4 %loop.acc.next = add i32 %loop.acc.1, %array.3.i %i.next = add nuw i32 %i, 1 %continue = icmp ult i32 %i.next, %n br i1 %continue, label %loop, label %exit exit: %result = phi i32 [ %loop.acc.next, %guarded1 ] ret i32 %result } define i32 @provably_taken(i32* %array, i32* %length.ptr) { ; CHECK-LABEL: @provably_taken( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ] ; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: br i1 false, label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64 ; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]] ; CHECK-NEXT: [[I_NEXT]] = add nuw nsw i32 [[I]], 1 ; CHECK-NEXT: br i1 true, label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ] ; CHECK-NEXT: ret i32 [[RESULT]] ; loop.preheader: %length = load i32, i32* %length.ptr, !range !2 br label %loop loop: ; preds = %guarded, %loop.preheader %loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ] %i = phi i32 [ %i.next, %guarded ], [ 0, %loop.preheader ] %within.bounds = icmp ult i32 %i, %length br i1 %within.bounds, label %guarded, label %deopt, !prof !0 deopt: ; preds = %loop call void @prevent_merging() ret i32 -1 guarded: ; preds = %loop %i.i64 = zext i32 %i to i64 %array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i.i64 %array.i = load i32, i32* %array.i.ptr, align 4 %loop.acc.next = add i32 %loop.acc, %array.i %i.next = add nuw i32 %i, 1 %continue = icmp slt i32 %i.next, 200 br i1 %continue, label %loop, label %exit exit: ; preds = %guarded %result = phi i32 [ %loop.acc.next, %guarded ] ret i32 %result } ; Non-latch exits can still be predicated define i32 @unconditional_latch(i32* %a, i32 %length) { ; CHECK-LABEL: @unconditional_latch( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: br i1 false, label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: br label [[LOOP]] ; loop.preheader: br label %loop loop: ; preds = %guarded, %loop.preheader %i = phi i32 [ %i.next, %guarded ], [ 400, %loop.preheader ] %within.bounds = icmp ult i32 %i, %length br i1 %within.bounds, label %guarded, label %deopt, !prof !0 deopt: ; preds = %loop call void @prevent_merging() ret i32 -1 guarded: ; preds = %loop %i.next = add i32 %i, 1 br label %loop } ; Side effect in loop must run proper number of times define i32 @unconditional_latch_with_side_effect(i32* %a, i32 %length) { ; CHECK-LABEL: @unconditional_latch_with_side_effect( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED:%.*]] ], [ 400, [[LOOP_PREHEADER:%.*]] ] ; CHECK-NEXT: [[WITHIN_BOUNDS:%.*]] = icmp ult i32 [[I]], [[LENGTH:%.*]] ; CHECK-NEXT: br i1 [[WITHIN_BOUNDS]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: store volatile i32 0, i32* [[A:%.*]] ; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1 ; CHECK-NEXT: br label [[LOOP]] ; loop.preheader: br label %loop loop: ; preds = %guarded, %loop.preheader %i = phi i32 [ %i.next, %guarded ], [ 400, %loop.preheader ] %within.bounds = icmp ult i32 %i, %length br i1 %within.bounds, label %guarded, label %deopt, !prof !0 deopt: ; preds = %loop call void @prevent_merging() ret i32 -1 guarded: ; preds = %loop store volatile i32 0, i32* %a %i.next = add i32 %i, 1 br label %loop } ; Demonstrate that this approach works with IVs of different steps, and types ; This version uses a manually lftred exit condition to work around an issue described ; in detail on next test. define i32 @different_ivs(i32* %array, i32 %length, i32 %n) { ; CHECK-LABEL: @different_ivs( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: [[N64:%.*]] = zext i32 [[N:%.*]] to i64 ; CHECK-NEXT: [[TMP0:%.*]] = icmp ugt i64 [[N64]], 1 ; CHECK-NEXT: [[UMAX:%.*]] = select i1 [[TMP0]], i64 [[N64]], i64 1 ; CHECK-NEXT: [[TMP1:%.*]] = add nsw i64 [[UMAX]], -1 ; CHECK-NEXT: [[TMP2:%.*]] = zext i32 [[LENGTH:%.*]] to i64 ; CHECK-NEXT: [[TMP3:%.*]] = icmp ult i64 [[TMP1]], [[TMP2]] ; CHECK-NEXT: [[UMIN:%.*]] = select i1 [[TMP3]], i64 [[TMP1]], i64 [[TMP2]] ; CHECK-NEXT: [[TMP4:%.*]] = zext i32 [[LENGTH]] to i64 ; CHECK-NEXT: [[TMP5:%.*]] = icmp ne i64 [[TMP4]], [[UMIN]] ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ] ; CHECK-NEXT: [[I:%.*]] = phi i64 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: br i1 [[TMP5]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I]] ; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]] ; CHECK-NEXT: [[I_NEXT]] = add nuw nsw i64 [[I]], 1 ; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i64 [[I_NEXT]], [[N64]] ; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ] ; CHECK-NEXT: ret i32 [[RESULT]] ; loop.preheader: %j.start = sub nuw nsw i32 %length, 1 %n64 = zext i32 %n to i64 br label %loop loop: %loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ] %i = phi i64 [ %i.next, %guarded ], [ 0, %loop.preheader ] %j = phi i32 [ %j.next, %guarded ], [ %j.start, %loop.preheader ] %within.bounds = icmp ne i32 %j, -1 br i1 %within.bounds, label %guarded, label %deopt, !prof !0 deopt: call void @prevent_merging() ret i32 -1 guarded: %array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i %array.i = load i32, i32* %array.i.ptr, align 4 %loop.acc.next = add i32 %loop.acc, %array.i %i.next = add nuw i64 %i, 1 %j.next = sub nuw i32 %j, 1 %continue = icmp ult i64 %i.next, %n64 br i1 %continue, label %loop, label %exit exit: %result = phi i32 [ %loop.acc.next, %guarded ] ret i32 %result } ; TODO: We're failing to compute an exit count for the bounds check. ; From some quick analysis, it looks like we don't handle -1 step ; in howManyLessThans. Should be a simple fix. define i32 @different_ivs2(i32* %array, i32 %length, i32 %n) { ; CHECK-LABEL: @different_ivs2( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[POS_LENGTH:%.*]] = icmp sgt i32 [[LENGTH:%.*]], 0 ; CHECK-NEXT: br i1 [[POS_LENGTH]], label [[LOOP_PREHEADER:%.*]], label [[EXIT:%.*]] ; CHECK: loop.preheader: ; CHECK-NEXT: [[J_START:%.*]] = sub nuw nsw i32 [[LENGTH]], 1 ; CHECK-NEXT: [[N64:%.*]] = zext i32 [[N:%.*]] to i64 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED:%.*]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: [[I:%.*]] = phi i64 [ [[I_NEXT:%.*]], [[GUARDED]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: [[J:%.*]] = phi i32 [ [[J_NEXT:%.*]], [[GUARDED]] ], [ [[J_START]], [[LOOP_PREHEADER]] ] ; CHECK-NEXT: [[WITHIN_BOUNDS:%.*]] = icmp ult i32 [[J]], [[LENGTH]] ; CHECK-NEXT: br i1 [[WITHIN_BOUNDS]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded: ; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I]] ; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]] ; CHECK-NEXT: [[I_NEXT]] = add nuw nsw i64 [[I]], 1 ; CHECK-NEXT: [[J_NEXT]] = sub nuw i32 [[J]], 1 ; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i64 [[I_NEXT]], [[N64]] ; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT_LOOPEXIT:%.*]] ; CHECK: exit.loopexit: ; CHECK-NEXT: [[LOOP_ACC_NEXT_LCSSA:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED]] ] ; CHECK-NEXT: br label [[EXIT]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[LOOP_ACC_NEXT_LCSSA]], [[EXIT_LOOPEXIT]] ] ; CHECK-NEXT: ret i32 [[RESULT]] ; entry: %pos_length = icmp sgt i32 %length, 0 br i1 %pos_length, label %loop.preheader, label %exit loop.preheader: %j.start = sub nuw nsw i32 %length, 1 %n64 = zext i32 %n to i64 br label %loop loop: %loop.acc = phi i32 [ %loop.acc.next, %guarded ], [ 0, %loop.preheader ] %i = phi i64 [ %i.next, %guarded ], [ 0, %loop.preheader ] %j = phi i32 [ %j.next, %guarded ], [ %j.start, %loop.preheader ] %within.bounds = icmp ult i32 %j, %length br i1 %within.bounds, label %guarded, label %deopt, !prof !0 deopt: call void @prevent_merging() ret i32 -1 guarded: %array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i %array.i = load i32, i32* %array.i.ptr, align 4 %loop.acc.next = add i32 %loop.acc, %array.i %i.next = add nuw i64 %i, 1 %j.next = sub nuw i32 %j, 1 %continue = icmp ult i64 %i.next, %n64 br i1 %continue, label %loop, label %exit exit: %result = phi i32 [ %loop.acc.next, %guarded ], [0, %entry] ret i32 %result } ; If we have a dominating exit (exit1) which can't be itself rewritten, we ; can't rewrite a later exit (exit2). Doing so would cause the loop to exit ; from the exit2 when it should have exited from exit1. define i32 @neg_dominating_exit(i32* %array, i32 %length, i32 %length2, i32 %n) { ; CHECK-LABEL: @neg_dominating_exit( ; CHECK-NEXT: loop.preheader: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[LOOP_ACC:%.*]] = phi i32 [ [[LOOP_ACC_NEXT:%.*]], [[GUARDED2:%.*]] ], [ 0, [[LOOP_PREHEADER:%.*]] ] ; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_NEXT:%.*]], [[GUARDED2]] ], [ 0, [[LOOP_PREHEADER]] ] ; CHECK-NEXT: [[WITHIN_BOUNDS:%.*]] = icmp ult i32 [[I]], [[LENGTH:%.*]] ; CHECK-NEXT: br i1 [[WITHIN_BOUNDS]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: ; CHECK-NEXT: [[RESULT:%.*]] = phi i32 [ [[LOOP_ACC]], [[LOOP]] ] ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 [[RESULT]] ; CHECK: guarded: ; CHECK-NEXT: [[WITHIN_BOUNDS2:%.*]] = icmp ult i32 [[I]], [[LENGTH2:%.*]] ; CHECK-NEXT: br i1 [[WITHIN_BOUNDS2]], label [[GUARDED2]], label [[DEOPT2:%.*]], !prof !0 ; CHECK: deopt2: ; CHECK-NEXT: call void @prevent_merging() ; CHECK-NEXT: ret i32 -1 ; CHECK: guarded2: ; CHECK-NEXT: [[I_I64:%.*]] = zext i32 [[I]] to i64 ; CHECK-NEXT: [[ARRAY_I_PTR:%.*]] = getelementptr inbounds i32, i32* [[ARRAY:%.*]], i64 [[I_I64]] ; CHECK-NEXT: [[ARRAY_I:%.*]] = load i32, i32* [[ARRAY_I_PTR]], align 4 ; CHECK-NEXT: [[LOOP_ACC_NEXT]] = add i32 [[LOOP_ACC]], [[ARRAY_I]] ; CHECK-NEXT: [[I_NEXT]] = add nuw i32 [[I]], 1 ; CHECK-NEXT: [[CONTINUE:%.*]] = icmp ult i32 [[I_NEXT]], [[N:%.*]] ; CHECK-NEXT: br i1 [[CONTINUE]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT2:%.*]] = phi i32 [ [[LOOP_ACC_NEXT]], [[GUARDED2]] ] ; CHECK-NEXT: ret i32 [[RESULT2]] ; loop.preheader: ; preds = %entry br label %loop loop: ; preds = %guarded, %loop.preheader %loop.acc = phi i32 [ %loop.acc.next, %guarded2 ], [ 0, %loop.preheader ] %i = phi i32 [ %i.next, %guarded2 ], [ 0, %loop.preheader ] %within.bounds = icmp ult i32 %i, %length br i1 %within.bounds, label %guarded, label %deopt, !prof !0 deopt: ; preds = %loop %result = phi i32 [ %loop.acc, %loop ] call void @prevent_merging() ret i32 %result guarded: ; preds = %loop %within.bounds2 = icmp ult i32 %i, %length2 br i1 %within.bounds2, label %guarded2, label %deopt2, !prof !0 deopt2: ; preds = %loop call void @prevent_merging() ret i32 -1 guarded2: ; preds = %loop %i.i64 = zext i32 %i to i64 %array.i.ptr = getelementptr inbounds i32, i32* %array, i64 %i.i64 %array.i = load i32, i32* %array.i.ptr, align 4 %loop.acc.next = add i32 %loop.acc, %array.i %i.next = add nuw i32 %i, 1 %continue = icmp ult i32 %i.next, %n br i1 %continue, label %loop, label %exit exit: ; preds = %guarded, %entry %result2 = phi i32 [ %loop.acc.next, %guarded2 ] ret i32 %result2 } declare i32 @llvm.experimental.deoptimize.i32(...) !0 = !{!"branch_weights", i32 1048576, i32 1} !1 = !{i32 1, i32 -2147483648} !2 = !{i32 0, i32 50}