1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals 2; Test that the strncpy library call simplifier works correctly. 3; 4; RUN: opt < %s -passes=instcombine -S | FileCheck %s 5 6target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128" 7 8@hello = constant [6 x i8] c"hello\00" 9@null = constant [1 x i8] zeroinitializer 10@null_hello = constant [7 x i8] c"\00hello\00" 11@a = common global [32 x i8] zeroinitializer, align 1 12@b = common global [32 x i8] zeroinitializer, align 1 13 14declare ptr @strncpy(ptr, ptr, i32) 15declare i32 @puts(ptr) 16 17; Check a bunch of strncpy invocations together. 18 19;. 20; CHECK: @hello = constant [6 x i8] c"hello\00" 21; CHECK: @null = constant [1 x i8] zeroinitializer 22; CHECK: @null_hello = constant [7 x i8] c"\00hello\00" 23; CHECK: @a = common global [32 x i8] zeroinitializer, align 1 24; CHECK: @b = common global [32 x i8] zeroinitializer, align 1 25; CHECK: @str = private unnamed_addr constant [32 x i8] c"hello\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00", align 1 26; CHECK: @str.1 = private unnamed_addr constant [32 x i8] c"hello\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00", align 1 27; CHECK: @str.2 = private unnamed_addr constant [8 x i8] c"hello\00\00\00", align 1 28;. 29define i32 @test_simplify1() { 30; CHECK-LABEL: @test_simplify1( 31; CHECK-NEXT: [[TARGET:%.*]] = alloca [1024 x i8], align 1 32; CHECK-NEXT: store i8 0, ptr [[TARGET]], align 1 33; CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr noundef nonnull align 1 dereferenceable(6) [[TARGET]], ptr noundef nonnull align 1 dereferenceable(6) @hello, i32 6, i1 false) 34; CHECK-NEXT: call void @llvm.memset.p0.i32(ptr noundef nonnull align 1 dereferenceable(42) [[TARGET]], i8 0, i32 42, i1 false) 35; CHECK-NEXT: call void @llvm.memset.p0.i32(ptr noundef nonnull align 1 dereferenceable(42) [[TARGET]], i8 0, i32 42, i1 false) 36; CHECK-NEXT: [[TMP1:%.*]] = call i32 @puts(ptr noundef nonnull dereferenceable(1) [[TARGET]]) 37; CHECK-NEXT: ret i32 0 38; 39 %target = alloca [1024 x i8] 40 store i8 0, ptr %target 41 42 %rslt1 = call ptr @strncpy(ptr %target, ptr @hello, i32 6) 43 44 %rslt2 = call ptr @strncpy(ptr %rslt1, ptr @null, i32 42) 45 46 %rslt3 = call ptr @strncpy(ptr %rslt2, ptr @null_hello, i32 42) 47 48 call i32 @puts( ptr %rslt3 ) 49 ret i32 0 50} 51 52; Check strncpy(x, "", y) -> memset(x, '\0', y, 1). 53 54define void @test_simplify2() { 55; CHECK-LABEL: @test_simplify2( 56; CHECK-NEXT: call void @llvm.memset.p0.i32(ptr noundef nonnull align 1 dereferenceable(32) @a, i8 0, i32 32, i1 false) 57; CHECK-NEXT: ret void 58; 59 60 call ptr @strncpy(ptr @a, ptr @null, i32 32) 61 ret void 62} 63 64; Check strncpy(x, y, 0) -> x. 65 66define ptr @test_simplify3() { 67; CHECK-LABEL: @test_simplify3( 68; CHECK-NEXT: ret ptr @a 69; 70 71 %ret = call ptr @strncpy(ptr @a, ptr @hello, i32 0) 72 ret ptr %ret 73} 74 75; Check strncpy(x, s, c) -> memcpy(x, s, c, 1) [s and c are constant]. 76 77define void @test_simplify4() { 78; CHECK-LABEL: @test_simplify4( 79; CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr noundef nonnull align 1 dereferenceable(6) @a, ptr noundef nonnull align 1 dereferenceable(6) @hello, i32 6, i1 false) 80; CHECK-NEXT: ret void 81; 82 83 call ptr @strncpy(ptr @a, ptr @hello, i32 6) 84 ret void 85} 86 87define void @test_simplify5(ptr %dst) { 88; CHECK-LABEL: @test_simplify5( 89; CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr noundef nonnull align 1 dereferenceable(32) [[DST:%.*]], ptr noundef nonnull align 1 dereferenceable(32) @str, i32 32, i1 false) 90; CHECK-NEXT: ret void 91; 92 call ptr @strncpy(ptr dereferenceable(8) %dst, ptr @hello, i32 32) 93 ret void 94} 95 96define void @test_simplify6(ptr %dst) { 97; CHECK-LABEL: @test_simplify6( 98; CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr noundef nonnull align 1 dereferenceable(80) [[DST:%.*]], ptr noundef nonnull align 1 dereferenceable(32) @str.1, i32 32, i1 false) 99; CHECK-NEXT: ret void 100; 101 call ptr @strncpy(ptr dereferenceable(80) %dst, ptr @hello, i32 32) 102 ret void 103} 104 105define void @test_simplify7(ptr %dst, i32 %n) { 106; CHECK-LABEL: @test_simplify7( 107; CHECK-NEXT: call void @llvm.memset.p0.i32(ptr align 1 dereferenceable(80) [[DST:%.*]], i8 0, i32 [[N:%.*]], i1 false) 108; CHECK-NEXT: ret void 109; 110; Unless N is known to be nonzero, strncpy(D, "", N) need not access any 111; bytes in D. 112; TODO: The argument, already annotated dereferenceable, should be 113; annotated noundef and nonnull by the transformation. See 114; https://reviews.llvm.org/D124633. 115 call ptr @strncpy(ptr dereferenceable(80) %dst, ptr @null, i32 %n) 116 ret void 117} 118 119define ptr @test1(ptr %dst, ptr %src, i32 %n) { 120; CHECK-LABEL: @test1( 121; CHECK-NEXT: [[RET:%.*]] = call ptr @strncpy(ptr nonnull [[DST:%.*]], ptr nonnull [[SRC:%.*]], i32 [[N:%.*]]) 122; CHECK-NEXT: ret ptr [[RET]] 123; 124; Unless N is known to be nonzero, strncpy(D, S, N) need not access any 125; bytes in either D or S. Verify that the call isn't annotated with 126; the dereferenceable attribute. 127; TODO: Both arguments should be annotated noundef in addition to nonnull. 128; See https://reviews.llvm.org/D124633. 129 %ret = call ptr @strncpy(ptr nonnull %dst, ptr nonnull %src, i32 %n) 130 ret ptr %ret 131} 132 133define ptr @test2(ptr %dst) { 134; CHECK-LABEL: @test2( 135; CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr noundef nonnull align 1 dereferenceable(5) [[DST:%.*]], ptr noundef nonnull align 1 dereferenceable(6) @hello, i32 5, i1 false) 136; CHECK-NEXT: ret ptr [[DST]] 137; 138 %ret = call ptr @strncpy(ptr nonnull %dst, ptr nonnull @hello, i32 5) 139 ret ptr %ret 140} 141 142define ptr @test3(ptr %dst, i32 %n) { 143; CHECK-LABEL: @test3( 144; CHECK-NEXT: call void @llvm.memset.p0.i32(ptr noalias noundef nonnull align 1 dereferenceable(5) [[DST:%.*]], i8 0, i32 5, i1 false) 145; CHECK-NEXT: ret ptr [[DST]] 146; 147 %ret = call ptr @strncpy(ptr noalias nonnull %dst, ptr nonnull @null, i32 5); 148 ret ptr %ret 149} 150 151define ptr @test4(ptr %dst, i32 %n) { 152; CHECK-LABEL: @test4( 153; CHECK-NEXT: call void @llvm.memset.p0.i32(ptr noalias noundef nonnull align 16 dereferenceable(5) [[DST:%.*]], i8 0, i32 5, i1 false) 154; CHECK-NEXT: ret ptr [[DST]] 155; 156 %ret = call ptr @strncpy(ptr align(16) noalias nonnull %dst, ptr nonnull @null, i32 5); 157 ret ptr %ret 158} 159 160; Check cases that shouldn't be simplified. 161 162define void @test_no_simplify1() { 163; CHECK-LABEL: @test_no_simplify1( 164; CHECK-NEXT: [[TMP1:%.*]] = call ptr @strncpy(ptr noundef nonnull dereferenceable(1) @a, ptr noundef nonnull dereferenceable(1) @b, i32 32) 165; CHECK-NEXT: ret void 166; 167 168 call ptr @strncpy(ptr @a, ptr @b, i32 32) 169 ret void 170} 171 172define void @test_no_simplify2() { 173; CHECK-LABEL: @test_no_simplify2( 174; CHECK-NEXT: store i64 478560413032, ptr @a, align 1 175; CHECK-NEXT: ret void 176; 177 178 call ptr @strncpy(ptr @a, ptr @hello, i32 8) 179 ret void 180} 181 182define ptr @test_no_simplify3(ptr %dst, ptr %src, i32 %count) { 183; CHECK-LABEL: @test_no_simplify3( 184; CHECK-NEXT: [[RET:%.*]] = musttail call ptr @strncpy(ptr [[DST:%.*]], ptr [[SRC:%.*]], i32 32) 185; CHECK-NEXT: ret ptr [[RET]] 186; 187 %ret = musttail call ptr @strncpy(ptr %dst, ptr %src, i32 32) 188 ret ptr %ret 189} 190 191define ptr @test_no_simplify4(ptr %dst, ptr %src, i32 %count) { 192; CHECK-LABEL: @test_no_simplify4( 193; CHECK-NEXT: [[RET:%.*]] = musttail call ptr @strncpy(ptr [[DST:%.*]], ptr [[SRC:%.*]], i32 6) 194; CHECK-NEXT: ret ptr [[RET]] 195; 196 %ret = musttail call ptr @strncpy(ptr %dst, ptr %src, i32 6) 197 ret ptr %ret 198} 199 200 201define void @test_no_incompatible_attr() { 202; CHECK-LABEL: @test_no_incompatible_attr( 203; CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr noundef nonnull align 1 dereferenceable(6) @a, ptr noundef nonnull align 1 dereferenceable(6) @hello, i32 6, i1 false) 204; CHECK-NEXT: ret void 205; 206 207 call ptr @strncpy(ptr @a, ptr @hello, i32 6) 208 ret void 209} 210;. 211; CHECK: attributes #[[ATTR0:[0-9]+]] = { nocallback nofree nounwind willreturn memory(argmem: readwrite) } 212; CHECK: attributes #[[ATTR1:[0-9]+]] = { nocallback nofree nounwind willreturn memory(argmem: write) } 213;. 214