1; Test that the strlen library call simplifier works correctly. 2; 3; RUN: opt < %s -instcombine -S | FileCheck %s 4 5target 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" 6 7@hello = constant [6 x i8] c"hello\00" 8@null = constant [1 x i8] zeroinitializer 9@null_hello = constant [7 x i8] c"\00hello\00" 10@nullstring = constant i8 0 11@a = common global [32 x i8] zeroinitializer, align 1 12 13declare i32 @strlen(i8*) 14 15; Check strlen(string constant) -> integer constant. 16 17define i32 @test_simplify1() { 18; CHECK-LABEL: @test_simplify1( 19 %hello_p = getelementptr [6 x i8]* @hello, i32 0, i32 0 20 %hello_l = call i32 @strlen(i8* %hello_p) 21 ret i32 %hello_l 22; CHECK-NEXT: ret i32 5 23} 24 25define i32 @test_simplify2() { 26; CHECK-LABEL: @test_simplify2( 27 %null_p = getelementptr [1 x i8]* @null, i32 0, i32 0 28 %null_l = call i32 @strlen(i8* %null_p) 29 ret i32 %null_l 30; CHECK-NEXT: ret i32 0 31} 32 33define i32 @test_simplify3() { 34; CHECK-LABEL: @test_simplify3( 35 %null_hello_p = getelementptr [7 x i8]* @null_hello, i32 0, i32 0 36 %null_hello_l = call i32 @strlen(i8* %null_hello_p) 37 ret i32 %null_hello_l 38; CHECK-NEXT: ret i32 0 39} 40 41define i32 @test_simplify4() { 42; CHECK-LABEL: @test_simplify4( 43 %len = tail call i32 @strlen(i8* @nullstring) nounwind 44 ret i32 %len 45; CHECK-NEXT: ret i32 0 46} 47 48; Check strlen(x) == 0 --> *x == 0. 49 50define i1 @test_simplify5() { 51; CHECK-LABEL: @test_simplify5( 52 %hello_p = getelementptr [6 x i8]* @hello, i32 0, i32 0 53 %hello_l = call i32 @strlen(i8* %hello_p) 54 %eq_hello = icmp eq i32 %hello_l, 0 55 ret i1 %eq_hello 56; CHECK-NEXT: ret i1 false 57} 58 59define i1 @test_simplify6() { 60; CHECK-LABEL: @test_simplify6( 61 %null_p = getelementptr [1 x i8]* @null, i32 0, i32 0 62 %null_l = call i32 @strlen(i8* %null_p) 63 %eq_null = icmp eq i32 %null_l, 0 64 ret i1 %eq_null 65; CHECK-NEXT: ret i1 true 66} 67 68; Check strlen(x) != 0 --> *x != 0. 69 70define i1 @test_simplify7() { 71; CHECK-LABEL: @test_simplify7( 72 %hello_p = getelementptr [6 x i8]* @hello, i32 0, i32 0 73 %hello_l = call i32 @strlen(i8* %hello_p) 74 %ne_hello = icmp ne i32 %hello_l, 0 75 ret i1 %ne_hello 76; CHECK-NEXT: ret i1 true 77} 78 79define i1 @test_simplify8() { 80; CHECK-LABEL: @test_simplify8( 81 %null_p = getelementptr [1 x i8]* @null, i32 0, i32 0 82 %null_l = call i32 @strlen(i8* %null_p) 83 %ne_null = icmp ne i32 %null_l, 0 84 ret i1 %ne_null 85; CHECK-NEXT: ret i1 false 86} 87 88; Check cases that shouldn't be simplified. 89 90define i32 @test_no_simplify1() { 91; CHECK-LABEL: @test_no_simplify1( 92 %a_p = getelementptr [32 x i8]* @a, i32 0, i32 0 93 %a_l = call i32 @strlen(i8* %a_p) 94; CHECK-NEXT: %a_l = call i32 @strlen 95 ret i32 %a_l 96; CHECK-NEXT: ret i32 %a_l 97} 98