; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt -indvars -S -indvars-predicate-loops=0 < %s | FileCheck %s target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" ; General case: without extra knowledge, trunc cannot be eliminated. define void @test_00(i64 %start, i32 %n) { ; ; CHECK-LABEL: @test_00( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add i64 [[IV]], 1 ; CHECK-NEXT: [[NARROW_IV:%.*]] = trunc i64 [[IV]] to i32 ; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 [[NARROW_IV]], [[N:%.*]] ; CHECK-NEXT: br i1 [[CMP]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ %start, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp slt i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } define void @test_01(i32 %n) { ; ; CHECK-LABEL: @test_01( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[SMAX:%.*]] = call i32 @llvm.smax.i32(i32 [[N:%.*]], i32 0) ; CHECK-NEXT: [[TMP0:%.*]] = add nuw i32 [[SMAX]], 1 ; CHECK-NEXT: [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[TMP0]] to i64 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i64 [[IV_NEXT]], [[WIDE_TRIP_COUNT]] ; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp slt i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; Max value at which we can eliminate trunc: SINT_MAX - 1. define void @test_02(i32 %n) { ; ; CHECK-LABEL: @test_02( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[SMAX:%.*]] = call i32 @llvm.smax.i32(i32 [[N:%.*]], i32 2147483646) ; CHECK-NEXT: [[TMP0:%.*]] = add nuw i32 [[SMAX]], 1 ; CHECK-NEXT: [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[TMP0]] to i64 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 2147483646, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i64 [[IV_NEXT]], [[WIDE_TRIP_COUNT]] ; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 2147483646, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp slt i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; If we start from SINT_MAX then the predicate is always false. define void @test_03(i32 %n) { ; ; CHECK-LABEL: @test_03( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: br i1 false, label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [2147483647, %entry], [%iv.next, %loop] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp slt i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; Minimum value at which we can apply the transform: SINT_MIN + 1. define void @test_04(i32 %n) { ; ; CHECK-LABEL: @test_04( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[SMAX:%.*]] = call i32 @llvm.smax.i32(i32 [[N:%.*]], i32 -2147483647) ; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[SMAX]], 1 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ -2147483647, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nsw i64 [[IV]], 1 ; CHECK-NEXT: [[LFTR_WIDEIV:%.*]] = trunc i64 [[IV_NEXT]] to i32 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[LFTR_WIDEIV]], [[TMP0]] ; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ -2147483647, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp slt i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; FIXME: Harmful LFTR should be thrown away. define void @test_05(i32 %n) { ; ; CHECK-LABEL: @test_05( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[N:%.*]], 1 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ -2147483648, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nsw i64 [[IV]], 1 ; CHECK-NEXT: [[LFTR_WIDEIV:%.*]] = trunc i64 [[IV_NEXT]] to i32 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[LFTR_WIDEIV]], [[TMP0]] ; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ -2147483648, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp slt i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; Trunc changes the actual value of the IV, so it is invalid to remove it: SINT_MIN - 1. define void @test_06(i32 %n) { ; ; CHECK-LABEL: @test_06( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: br i1 false, label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ -2147483649, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp slt i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; General case: without extra knowledge, trunc cannot be eliminated. define void @test_00_unsigned(i64 %start, i32 %n) { ; CHECK-LABEL: @test_00_unsigned( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ [[START:%.*]], [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add i64 [[IV]], 1 ; CHECK-NEXT: [[NARROW_IV:%.*]] = trunc i64 [[IV]] to i32 ; CHECK-NEXT: [[CMP:%.*]] = icmp ult i32 [[NARROW_IV]], [[N:%.*]] ; CHECK-NEXT: br i1 [[CMP]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ %start, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp ult i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; FIXME: Harmful LFTR should be thrown away. define void @test_01_unsigned(i32 %n) { ; CHECK-LABEL: @test_01_unsigned( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[N:%.*]], 1 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1 ; CHECK-NEXT: [[LFTR_WIDEIV:%.*]] = trunc i64 [[IV_NEXT]] to i32 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[LFTR_WIDEIV]], [[TMP0]] ; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp ult i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; Max value at which we can eliminate trunc: UINT_MAX - 1. define void @test_02_unsigned(i32 %n) { ; CHECK-LABEL: @test_02_unsigned( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[UMAX:%.*]] = call i32 @llvm.umax.i32(i32 [[N:%.*]], i32 -2) ; CHECK-NEXT: [[TMP0:%.*]] = add nsw i32 [[UMAX]], 1 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 4294967294, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1 ; CHECK-NEXT: [[LFTR_WIDEIV:%.*]] = trunc i64 [[IV_NEXT]] to i32 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[LFTR_WIDEIV]], [[TMP0]] ; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 4294967294, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp ult i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; If we start from UINT_MAX then the predicate is always false. define void @test_03_unsigned(i32 %n) { ; CHECK-LABEL: @test_03_unsigned( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: br i1 false, label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 4294967295, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp ult i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; Minimum value at which we can apply the transform: UINT_MIN. define void @test_04_unsigned(i32 %n) { ; CHECK-LABEL: @test_04_unsigned( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[N:%.*]], 1 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1 ; CHECK-NEXT: [[LFTR_WIDEIV:%.*]] = trunc i64 [[IV_NEXT]] to i32 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[LFTR_WIDEIV]], [[TMP0]] ; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp ult i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; Start from 1. define void @test_05_unsigned(i32 %n) { ; CHECK-LABEL: @test_05_unsigned( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[UMAX:%.*]] = call i32 @llvm.umax.i32(i32 [[N:%.*]], i32 1) ; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[UMAX]], 1 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 1, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1 ; CHECK-NEXT: [[LFTR_WIDEIV:%.*]] = trunc i64 [[IV_NEXT]] to i32 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i32 [[LFTR_WIDEIV]], [[TMP0]] ; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 1, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp ult i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; Trunc changes the actual value of the IV, so it is invalid to remove it: UINT_MIN - 1. define void @test_06_unsigned(i32 %n) { ; CHECK-LABEL: @test_06_unsigned( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: br i1 false, label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ -1, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp ult i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; Do not eliminate trunc if it is used by something different from icmp. define void @test_07(i32* %p, i32 %n) { ; CHECK-LABEL: @test_07( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[SMAX:%.*]] = call i32 @llvm.smax.i32(i32 [[N:%.*]], i32 0) ; CHECK-NEXT: [[TMP0:%.*]] = add nuw i32 [[SMAX]], 1 ; CHECK-NEXT: [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[TMP0]] to i64 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1 ; CHECK-NEXT: [[NARROW_IV:%.*]] = trunc i64 [[IV]] to i32 ; CHECK-NEXT: store i32 [[NARROW_IV]], i32* [[P:%.*]], align 4 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i64 [[IV_NEXT]], [[WIDE_TRIP_COUNT]] ; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 store i32 %narrow.iv, i32* %p %cmp = icmp slt i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; Check that we can eliminate both signed and unsigned compare. define void @test_08(i32 %n) { ; CHECK-LABEL: @test_08( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[ZEXT:%.*]] = zext i32 [[N:%.*]] to i64 ; CHECK-NEXT: [[SEXT:%.*]] = sext i32 [[N]] to i64 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 1, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1 ; CHECK-NEXT: [[TMP0:%.*]] = icmp slt i64 [[IV]], [[SEXT]] ; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i64 [[IV]], [[ZEXT]] ; CHECK-NEXT: [[CMP:%.*]] = and i1 [[TMP0]], [[TMP1]] ; CHECK-NEXT: br i1 [[CMP]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 1, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp1 = icmp slt i32 %narrow.iv, %n %cmp2 = icmp ult i32 %narrow.iv, %n %cmp = and i1 %cmp1, %cmp2 br i1 %cmp, label %loop, label %exit exit: ret void } ; Widen NE as unsigned. define void @test_09(i32 %n) { ; CHECK-LABEL: @test_09( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[ZEXT:%.*]] = zext i32 [[N:%.*]] to i64 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1 ; CHECK-NEXT: [[TMP0:%.*]] = icmp ne i64 [[IV]], [[ZEXT]] ; CHECK-NEXT: br i1 [[TMP0]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp ne i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } ; Widen NE as signed. define void @test_10(i32 %n) { ; CHECK-LABEL: @test_10( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[N:%.*]], 100 ; CHECK-NEXT: [[TMP1:%.*]] = zext i32 [[TMP0]] to i64 ; CHECK-NEXT: [[UMIN:%.*]] = call i64 @llvm.umin.i64(i64 [[TMP1]], i64 90) ; CHECK-NEXT: [[TMP2:%.*]] = add nuw nsw i64 [[UMIN]], -99 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ -100, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i64 [[IV_NEXT]], [[TMP2]] ; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ -100, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv to i32 %trunccmp = icmp ne i32 %narrow.iv, %n %negcmp = icmp slt i64 %iv, -10 %cmp = and i1 %trunccmp, %negcmp br i1 %cmp, label %loop, label %exit exit: ret void } define void @test_11() { ; CHECK-LABEL: @test_11( ; CHECK-NEXT: br label [[BB1:%.*]] ; CHECK: bb1: ; CHECK-NEXT: br i1 undef, label [[BB2:%.*]], label [[BB6:%.*]] ; CHECK: bb2: ; CHECK-NEXT: br i1 undef, label [[BB3:%.*]], label [[BB4:%.*]] ; CHECK: bb3: ; CHECK-NEXT: br label [[BB4]] ; CHECK: bb4: ; CHECK-NEXT: br label [[BB6]] ; CHECK: bb5: ; CHECK-NEXT: [[_TMP24:%.*]] = icmp slt i16 poison, 0 ; CHECK-NEXT: br i1 [[_TMP24]], label [[BB5:%.*]], label [[BB5]] ; CHECK: bb6: ; CHECK-NEXT: br i1 false, label [[BB1]], label [[BB7:%.*]] ; CHECK: bb7: ; CHECK-NEXT: ret void ; br label %bb1 bb1: ; preds = %bb6, %0 %e.5.0 = phi i32 [ 0, %0 ], [ %_tmp32, %bb6 ] br i1 undef, label %bb2, label %bb6 bb2: ; preds = %bb1 %_tmp15 = trunc i32 %e.5.0 to i16 br i1 undef, label %bb3, label %bb4 bb3: ; preds = %bb2 br label %bb4 bb4: ; preds = %bb3, %bb2 br label %bb6 bb5: ; preds = %bb5, %bb5 %_tmp24 = icmp slt i16 %_tmp15, 0 br i1 %_tmp24, label %bb5, label %bb5 bb6: ; preds = %bb4, %bb1 %_tmp32 = add nuw nsw i32 %e.5.0, 1 br i1 false, label %bb1, label %bb7 bb7: ; preds = %bb6 ret void } ; Show that we can turn signed comparison to unsigned and use zext while ; comparing non-negative values. define void @test_12(i32* %p) { ; CHECK-LABEL: @test_12( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[N:%.*]] = load i32, i32* [[P:%.*]], align 4, !range [[RNG0:![0-9]+]] ; CHECK-NEXT: [[SMAX:%.*]] = call i32 @llvm.smax.i32(i32 [[N]], i32 1) ; CHECK-NEXT: [[WIDE_TRIP_COUNT:%.*]] = zext i32 [[SMAX]] to i64 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 1 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp ne i64 [[IV_NEXT]], [[WIDE_TRIP_COUNT]] ; CHECK-NEXT: br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: %n = load i32, i32* %p, !range !0 br label %loop loop: %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ] %iv.next = add i64 %iv, 1 %narrow.iv = trunc i64 %iv.next to i32 %cmp = icmp slt i32 %narrow.iv, %n br i1 %cmp, label %loop, label %exit exit: ret void } define void @test_13a(i32 %n) { ; ; CHECK-LABEL: @test_13a( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[ZEXT:%.*]] = zext i32 1024 to i64 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 2 ; CHECK-NEXT: [[TMP0:%.*]] = icmp ne i64 [[IV]], [[ZEXT]] ; CHECK-NEXT: br i1 [[TMP0]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ] %iv.next = add nsw nuw i64 %iv, 2 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp ne i32 1024, %narrow.iv br i1 %cmp, label %loop, label %exit exit: ret void } define void @test_13b(i32 %n) { ; ; CHECK-LABEL: @test_13b( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[ZEXT:%.*]] = zext i32 1024 to i64 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 2 ; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i64 [[IV]], [[ZEXT]] ; CHECK-NEXT: br i1 [[TMP0]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ] %iv.next = add nsw nuw i64 %iv, 2 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp ugt i32 1024, %narrow.iv br i1 %cmp, label %loop, label %exit exit: ret void } define void @test_13c(i32 %n) { ; ; CHECK-LABEL: @test_13c( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[ZEXT:%.*]] = zext i32 1024 to i64 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nuw nsw i64 [[IV]], 2 ; CHECK-NEXT: [[TMP0:%.*]] = icmp ult i64 [[IV]], [[ZEXT]] ; CHECK-NEXT: br i1 [[TMP0]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ] %iv.next = add nsw nuw i64 %iv, 2 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp sgt i32 1024, %narrow.iv br i1 %cmp, label %loop, label %exit exit: ret void } define void @test_13d(i32 %n) { ; ; CHECK-LABEL: @test_13d( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[SEXT:%.*]] = sext i32 1024 to i64 ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i64 [ -20, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IV_NEXT]] = add nsw i64 [[IV]], 2 ; CHECK-NEXT: [[TMP0:%.*]] = icmp slt i64 [[IV]], [[SEXT]] ; CHECK-NEXT: br i1 [[TMP0]], label [[LOOP]], label [[EXIT:%.*]] ; CHECK: exit: ; CHECK-NEXT: ret void ; entry: br label %loop loop: %iv = phi i64 [ -20, %entry ], [ %iv.next, %loop ] %iv.next = add nsw i64 %iv, 2 %narrow.iv = trunc i64 %iv to i32 %cmp = icmp sgt i32 1024, %narrow.iv br i1 %cmp, label %loop, label %exit exit: ret void } !0 = !{i32 0, i32 1000}