1; Test that the strncmp library call simplifier works correctly. 2; RUN: opt < %s -instcombine -S | FileCheck %s 3 4target 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" 5 6@hello = constant [6 x i8] c"hello\00" 7@hell = constant [5 x i8] c"hell\00" 8@bell = constant [5 x i8] c"bell\00" 9@null = constant [1 x i8] zeroinitializer 10 11declare i32 @strncmp(i8*, i8*, i32) 12 13; strncmp("", x, n) -> -*x 14define i32 @test1(i8* %str2) { 15; CHECK-LABEL: @test1( 16; CHECK: %strcmpload = load i8, i8* %str 17; CHECK: %1 = zext i8 %strcmpload to i32 18; CHECK: %2 = sub nsw i32 0, %1 19; CHECK: ret i32 %2 20 21 %str1 = getelementptr inbounds [1 x i8], [1 x i8]* @null, i32 0, i32 0 22 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 10) 23 ret i32 %temp1 24} 25 26; strncmp(x, "", n) -> *x 27define i32 @test2(i8* %str1) { 28; CHECK-LABEL: @test2( 29; CHECK: %strcmpload = load i8, i8* %str1 30; CHECK: %1 = zext i8 %strcmpload to i32 31; CHECK: ret i32 %1 32 33 %str2 = getelementptr inbounds [1 x i8], [1 x i8]* @null, i32 0, i32 0 34 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 10) 35 ret i32 %temp1 36} 37 38; strncmp(x, y, n) -> cnst 39define i32 @test3() { 40; CHECK-LABEL: @test3( 41; CHECK: ret i32 -1 42 43 %str1 = getelementptr inbounds [5 x i8], [5 x i8]* @hell, i32 0, i32 0 44 %str2 = getelementptr inbounds [6 x i8], [6 x i8]* @hello, i32 0, i32 0 45 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 10) 46 ret i32 %temp1 47} 48 49define i32 @test4() { 50; CHECK-LABEL: @test4( 51; CHECK: ret i32 1 52 53 %str1 = getelementptr inbounds [5 x i8], [5 x i8]* @hell, i32 0, i32 0 54 %str2 = getelementptr inbounds [1 x i8], [1 x i8]* @null, i32 0, i32 0 55 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 10) 56 ret i32 %temp1 57} 58 59define i32 @test5() { 60; CHECK-LABEL: @test5( 61; CHECK: ret i32 0 62 63 %str1 = getelementptr inbounds [5 x i8], [5 x i8]* @hell, i32 0, i32 0 64 %str2 = getelementptr inbounds [6 x i8], [6 x i8]* @hello, i32 0, i32 0 65 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 4) 66 ret i32 %temp1 67} 68 69; strncmp(x,y,1) -> memcmp(x,y,1) 70define i32 @test6(i8* %str1, i8* %str2) { 71; CHECK-LABEL: @test6( 72; CHECK: [[LOAD1:%[a-z]+]] = load i8, i8* %str1, align 1 73; CHECK: [[ZEXT1:%[a-z]+]] = zext i8 [[LOAD1]] to i32 74; CHECK: [[LOAD2:%[a-z]+]] = load i8, i8* %str2, align 1 75; CHECK: [[ZEXT2:%[a-z]+]] = zext i8 [[LOAD2]] to i32 76; CHECK: [[RET:%[a-z]+]] = sub nsw i32 [[ZEXT1]], [[ZEXT2]] 77; CHECK: ret i32 [[RET]] 78 79 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 1) 80 ret i32 %temp1 81} 82 83; strncmp(x,y,0) -> 0 84define i32 @test7(i8* %str1, i8* %str2) { 85; CHECK-LABEL: @test7( 86; CHECK: ret i32 0 87 88 %temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 0) 89 ret i32 %temp1 90} 91 92; strncmp(x,x,n) -> 0 93define i32 @test8(i8* %str, i32 %n) { 94; CHECK-LABEL: @test8( 95; CHECK: ret i32 0 96 97 %temp1 = call i32 @strncmp(i8* %str, i8* %str, i32 %n) 98 ret i32 %temp1 99} 100