llvm-project/llvm/test/Transforms/InstCombine/memcmp-1.ll

124 lines
3.8 KiB
LLVM

; Test that the memcmp library call simplifier works correctly.
;
; RUN: opt < %s -instcombine -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-n8:16:32:64"
@foo = constant [4 x i8] c"foo\00"
@hel = constant [4 x i8] c"hel\00"
@hello_u = constant [8 x i8] c"hello_u\00"
declare i32 @memcmp(i8*, i8*, i32)
; Check memcmp(mem, mem, size) -> 0.
define i32 @test_simplify1(i8* %mem, i32 %size) {
; CHECK-LABEL: @test_simplify1(
%ret = call i32 @memcmp(i8* %mem, i8* %mem, i32 %size)
ret i32 %ret
; CHECK: ret i32 0
}
; Check memcmp(mem1, mem2, 0) -> 0.
define i32 @test_simplify2(i8* %mem1, i8* %mem2) {
; CHECK-LABEL: @test_simplify2(
%ret = call i32 @memcmp(i8* %mem1, i8* %mem2, i32 0)
ret i32 %ret
; CHECK: ret i32 0
}
;; Check memcmp(mem1, mem2, 1) -> *(unsigned char*)mem1 - *(unsigned char*)mem2.
define i32 @test_simplify3(i8* %mem1, i8* %mem2) {
; CHECK-LABEL: @test_simplify3(
%ret = call i32 @memcmp(i8* %mem1, i8* %mem2, i32 1)
; CHECK: [[LOAD1:%[a-z]+]] = load i8, i8* %mem1, align 1
; CHECK: [[ZEXT1:%[a-z]+]] = zext i8 [[LOAD1]] to i32
; CHECK: [[LOAD2:%[a-z]+]] = load i8, i8* %mem2, align 1
; CHECK: [[ZEXT2:%[a-z]+]] = zext i8 [[LOAD2]] to i32
; CHECK: [[RET:%[a-z]+]] = sub nsw i32 [[ZEXT1]], [[ZEXT2]]
ret i32 %ret
; CHECK: ret i32 [[RET]]
}
; Check memcmp(mem1, mem2, size) -> cnst, where all arguments are constants.
define i32 @test_simplify4() {
; CHECK-LABEL: @test_simplify4(
%mem1 = getelementptr [4 x i8], [4 x i8]* @hel, i32 0, i32 0
%mem2 = getelementptr [8 x i8], [8 x i8]* @hello_u, i32 0, i32 0
%ret = call i32 @memcmp(i8* %mem1, i8* %mem2, i32 3)
ret i32 %ret
; CHECK: ret i32 0
}
define i32 @test_simplify5() {
; CHECK-LABEL: @test_simplify5(
%mem1 = getelementptr [4 x i8], [4 x i8]* @hel, i32 0, i32 0
%mem2 = getelementptr [4 x i8], [4 x i8]* @foo, i32 0, i32 0
%ret = call i32 @memcmp(i8* %mem1, i8* %mem2, i32 3)
ret i32 %ret
; CHECK: ret i32 1
}
define i32 @test_simplify6() {
; CHECK-LABEL: @test_simplify6(
%mem1 = getelementptr [4 x i8], [4 x i8]* @foo, i32 0, i32 0
%mem2 = getelementptr [4 x i8], [4 x i8]* @hel, i32 0, i32 0
%ret = call i32 @memcmp(i8* %mem1, i8* %mem2, i32 3)
ret i32 %ret
; CHECK: ret i32 -1
}
; Check memcmp(mem1, mem2, 8)==0 -> *(int64_t*)mem1 == *(int64_t*)mem2
define i1 @test_simplify7(i64 %x, i64 %y) {
; CHECK-LABEL: @test_simplify7(
%x.addr = alloca i64, align 8
%y.addr = alloca i64, align 8
store i64 %x, i64* %x.addr, align 8
store i64 %y, i64* %y.addr, align 8
%xptr = bitcast i64* %x.addr to i8*
%yptr = bitcast i64* %y.addr to i8*
%call = call i32 @memcmp(i8* %xptr, i8* %yptr, i32 8)
%cmp = icmp eq i32 %call, 0
ret i1 %cmp
; CHECK: %cmp = icmp eq i64 %x, %y
; CHECK: ret i1 %cmp
}
; Check memcmp(mem1, mem2, 4)==0 -> *(int32_t*)mem1 == *(int32_t*)mem2
define i1 @test_simplify8(i32 %x, i32 %y) {
; CHECK-LABEL: @test_simplify8(
%x.addr = alloca i32, align 4
%y.addr = alloca i32, align 4
store i32 %x, i32* %x.addr, align 4
store i32 %y, i32* %y.addr, align 4
%xptr = bitcast i32* %x.addr to i8*
%yptr = bitcast i32* %y.addr to i8*
%call = call i32 @memcmp(i8* %xptr, i8* %yptr, i32 4)
%cmp = icmp eq i32 %call, 0
ret i1 %cmp
; CHECK: %cmp = icmp eq i32 %x, %y
; CHECK: ret i1 %cmp
}
; Check memcmp(mem1, mem2, 2)==0 -> *(int16_t*)mem1 == *(int16_t*)mem2
define i1 @test_simplify9(i16 %x, i16 %y) {
; CHECK-LABEL: @test_simplify9(
%x.addr = alloca i16, align 2
%y.addr = alloca i16, align 2
store i16 %x, i16* %x.addr, align 2
store i16 %y, i16* %y.addr, align 2
%xptr = bitcast i16* %x.addr to i8*
%yptr = bitcast i16* %y.addr to i8*
%call = call i32 @memcmp(i8* %xptr, i8* %yptr, i32 2)
%cmp = icmp eq i32 %call, 0
ret i1 %cmp
; CHECK: %cmp = icmp eq i16 %x, %y
; CHECK: ret i1 %cmp
}