1 ; Test that the strstr library call simplifier works correctly. 2 ; 3 ; RUN: opt < %s -instcombine -S | FileCheck %s 4 5 target 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 12 declare i8* @strstr(i8*, i8*) 13 14 ; Check strstr(str, "") -> str. 15 16 define i8* @test_simplify1(i8* %str) { 17 ; CHECK-LABEL: @test_simplify1( 18 %pat = getelementptr inbounds [1 x i8], [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 26 define i8* @test_simplify2(i8* %str) { 27 ; CHECK-LABEL: @test_simplify2( 28 %pat = getelementptr inbounds [2 x i8], [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 36 define i8* @test_simplify3() { 37 ; CHECK-LABEL: @test_simplify3( 38 %str = getelementptr inbounds [6 x i8], [6 x i8]* @.str2, i32 0, i32 0 39 %pat = getelementptr inbounds [4 x i8], [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], [6 x i8]* @.str2, i64 0, i64 1) 43 } 44 45 ; Check strstr(str, str) -> str. 46 47 define 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 56 define 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
