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1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py2; RUN: opt < %s -passes=sccp -S | FileCheck %s3 4; This is a basic correctness check for constant propagation. The add5; instruction should be eliminated.6 7define i32 @test1(i1 %B) {8; CHECK-LABEL: @test1(9; CHECK-NEXT: br i1 [[B:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]10; CHECK: BB1:11; CHECK-NEXT: br label [[BB3:%.*]]12; CHECK: BB2:13; CHECK-NEXT: br label [[BB3]]14; CHECK: BB3:15; CHECK-NEXT: [[RET:%.*]] = phi i32 [ 0, [[BB1]] ], [ 1, [[BB2]] ]16; CHECK-NEXT: ret i32 [[RET]]17;18 br i1 %B, label %BB1, label %BB219BB1: ; preds = %020 %Val = add i32 0, 0 ; <i32> [#uses=1]21 br label %BB322BB2: ; preds = %023 br label %BB324BB3: ; preds = %BB2, %BB125 %Ret = phi i32 [ %Val, %BB1 ], [ 1, %BB2 ] ; <i32> [#uses=1]26 ret i32 %Ret27 28}29 30; This is the test case taken from appel's book that illustrates a hard case31; that SCCP gets right.32;33define i32 @test2(i32 %i0, i32 %j0) {34; CHECK-LABEL: @test2(35; CHECK-NEXT: BB1:36; CHECK-NEXT: br label [[BB2:%.*]]37; CHECK: BB2:38; CHECK-NEXT: [[K2:%.*]] = phi i32 [ [[K3:%.*]], [[BB7:%.*]] ], [ 0, [[BB1:%.*]] ]39; CHECK-NEXT: [[KCOND:%.*]] = icmp slt i32 [[K2]], 10040; CHECK-NEXT: br i1 [[KCOND]], label [[BB3:%.*]], label [[BB4:%.*]]41; CHECK: BB3:42; CHECK-NEXT: br label [[BB5:%.*]]43; CHECK: BB4:44; CHECK-NEXT: ret i32 145; CHECK: BB5:46; CHECK-NEXT: [[K3]] = add nsw i32 [[K2]], 147; CHECK-NEXT: br label [[BB7]]48; CHECK: BB7:49; CHECK-NEXT: br label [[BB2]]50;51BB1:52 br label %BB253BB2:54 %j2 = phi i32 [ %j4, %BB7 ], [ 1, %BB1 ]55 %k2 = phi i32 [ %k4, %BB7 ], [ 0, %BB1 ]56 %kcond = icmp slt i32 %k2, 10057 br i1 %kcond, label %BB3, label %BB458BB3:59 %jcond = icmp slt i32 %j2, 2060 br i1 %jcond, label %BB5, label %BB661BB4:62 ret i32 %j263BB5:64 %k3 = add i32 %k2, 165 br label %BB766BB6:67 %k5 = add i32 %k2, 168 br label %BB769BB7:70 %j4 = phi i32 [ 1, %BB5 ], [ %k2, %BB6 ]71 %k4 = phi i32 [ %k3, %BB5 ], [ %k5, %BB6 ]72 br label %BB273}74 75