1; Test that the strstr library call simplifier works correctly. 2; 3; RUN: opt < %s -instcombine -S | FileCheck %s 4 5target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" 6 7@.str = private constant [1 x i8] zeroinitializer 8@.str1 = private constant [2 x i8] c"a\00" 9@.str2 = private constant [6 x i8] c"abcde\00" 10@.str3 = private constant [4 x i8] c"bcd\00" 11 12declare i8* @strstr(i8*, i8*) 13 14; Check strstr(str, "") -> str. 15 16define i8* @test_simplify1(i8* %str) { 17; CHECK-LABEL: @test_simplify1( 18 %pat = getelementptr inbounds [1 x i8]* @.str, i32 0, i32 0 19 %ret = call i8* @strstr(i8* %str, i8* %pat) 20 ret i8* %ret 21; CHECK-NEXT: ret i8* %str 22} 23 24; Check strstr(str, "a") -> strchr(str, 'a'). 25 26define i8* @test_simplify2(i8* %str) { 27; CHECK-LABEL: @test_simplify2( 28 %pat = getelementptr inbounds [2 x i8]* @.str1, i32 0, i32 0 29 %ret = call i8* @strstr(i8* %str, i8* %pat) 30 ret i8* %ret 31; CHECK-NEXT: @strchr(i8* %str, i32 97) 32} 33 34; Check strstr("abcde", "bcd") -> "abcde" + 1. 35 36define i8* @test_simplify3() { 37; CHECK-LABEL: @test_simplify3( 38 %str = getelementptr inbounds [6 x i8]* @.str2, i32 0, i32 0 39 %pat = getelementptr inbounds [4 x i8]* @.str3, i32 0, i32 0 40 %ret = call i8* @strstr(i8* %str, i8* %pat) 41 ret i8* %ret 42; CHECK-NEXT: getelementptr inbounds ([6 x i8]* @.str2, i64 0, i64 1) 43} 44 45; Check strstr(str, str) -> str. 46 47define i8* @test_simplify4(i8* %str) { 48; CHECK-LABEL: @test_simplify4( 49 %ret = call i8* @strstr(i8* %str, i8* %str) 50 ret i8* %ret 51; CHECK-NEXT: ret i8* %str 52} 53 54; Check strstr(str, pat) == str -> strncmp(str, pat, strlen(str)) == 0. 55 56define i1 @test_simplify5(i8* %str, i8* %pat) { 57; CHECK-LABEL: @test_simplify5( 58 %ret = call i8* @strstr(i8* %str, i8* %pat) 59 %cmp = icmp eq i8* %ret, %str 60 ret i1 %cmp 61; CHECK: [[LEN:%[a-z]+]] = call {{i[0-9]+}} @strlen(i8* %pat) 62; CHECK: [[NCMP:%[a-z]+]] = call {{i[0-9]+}} @strncmp(i8* %str, i8* %pat, {{i[0-9]+}} [[LEN]]) 63; CHECK: icmp eq {{i[0-9]+}} [[NCMP]], 0 64; CHECK: ret i1 65} 66