llvm-6502/test/Transforms/SimplifyLibCalls/StrNCmp.ll
Eli Friedman 792860883e PR11061: Make simplifylibcalls fold strcmp("", x) correctly.
While I'm here, fix the related issue with strncmp, add some actual tests for strcmp and strncmp, and start using StringRef::compare for constant folding instead of using strcmp/strncmp so that the optimized IR isn't dependent on the host's implementation of strcmp.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141227 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-05 22:27:16 +00:00

79 lines
2.5 KiB
LLVM

; Test that the StrCmpOptimizer works correctly
; RUN: opt < %s -simplify-libcalls -S | FileCheck %s
target 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"
@hello = constant [6 x i8] c"hello\00" ; <[6 x i8]*> [#uses=1]
@hell = constant [5 x i8] c"hell\00" ; <[5 x i8]*> [#uses=1]
@bell = constant [5 x i8] c"bell\00" ; <[5 x i8]*> [#uses=1]
@null = constant [1 x i8] zeroinitializer ; <[1 x i8]*> [#uses=1]
declare i32 @strncmp(i8*, i8*, i32)
; strcmp("", x) -> -*x
define i32 @test1(i8* %str) {
%temp1 = call i32 @strncmp(i8* getelementptr inbounds ([1 x i8]* @null, i32 0, i32 0), i8* %str, i32 10)
ret i32 %temp1
; CHECK: @test1
; CHECK: %strcmpload = load i8* %str
; CHECK: %1 = zext i8 %strcmpload to i32
; CHECK: %temp1 = sub i32 0, %1
; CHECK: ret i32 %temp1
}
; strcmp(x, "") -> *x
define i32 @test2(i8* %str) {
%temp1 = call i32 @strncmp(i8* %str, i8* getelementptr inbounds ([1 x i8]* @null, i32 0, i32 0), i32 10)
ret i32 %temp1
; CHECK: @test2
; CHECK: %strcmpload = load i8* %str
; CHECK: %temp1 = zext i8 %strcmpload to i32
; CHECK: ret i32 %temp1
}
; strncmp(x, y, n) -> cnst
define i32 @test3() {
%temp1 = call i32 @strncmp(i8* getelementptr inbounds ([5 x i8]* @hell, i32 0, i32 0), i8* getelementptr inbounds ([6 x i8]* @hello, i32 0, i32 0), i32 10)
ret i32 %temp1
; CHECK: @test3
; CHECK: ret i32 -1
}
define i32 @test4() {
%temp1 = call i32 @strncmp(i8* getelementptr inbounds ([5 x i8]* @hell, i32 0, i32 0), i8* getelementptr inbounds ([1 x i8]* @null, i32 0, i32 0), i32 10)
ret i32 %temp1
; CHECK: @test4
; CHECK: ret i32 1
}
define i32 @test5() {
%temp1 = call i32 @strncmp(i8* getelementptr inbounds ([5 x i8]* @hell, i32 0, i32 0), i8* getelementptr inbounds ([6 x i8]* @hello, i32 0, i32 0), i32 4)
ret i32 %temp1
; CHECK: @test5
; CHECK: ret i32 0
}
; strncmp(x,y,1) -> memcmp(x,y,1)
define i32 @test6(i8* %str1, i8* %str2) {
%temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 1)
ret i32 %temp1
; CHECK: @test6
; CHECK: load i8*
; CHECK: load i8*
; CHECK: sub i32
}
; strncmp(x,y,0) -> 0
define i32 @test7(i8* %str1, i8* %str2) {
%temp1 = call i32 @strncmp(i8* %str1, i8* %str2, i32 0)
ret i32 %temp1
; CHECK: @test7
; CHECK: ret i32 0
}
; strncmp(x,x,n) -> 0
define i32 @test8(i8* %str, i32 %n) {
%temp1 = call i32 @strncmp(i8* %str, i8* %str, i32 %n)
ret i32 %temp1
; CHECK: @test8
; CHECK: ret i32 0
}