; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals
; Test that the strncpy library call simplifier works correctly.
;
; RUN: opt < %s -passes=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"
@hello = constant [6 x i8] c"hello\00"
@null = constant [1 x i8] zeroinitializer
@null_hello = constant [7 x i8] c"\00hello\00"
@a = common global [32 x i8] zeroinitializer, align 1
@b = common global [32 x i8] zeroinitializer, align 1
declare ptr @strncpy(ptr, ptr, i32)
declare i32 @puts(ptr)
; Check a bunch of strncpy invocations together.
;.
; CHECK: @hello = constant [6 x i8] c"hello\00"
; CHECK: @null = constant [1 x i8] zeroinitializer
; CHECK: @null_hello = constant [7 x i8] c"\00hello\00"
; CHECK: @a = common global [32 x i8] zeroinitializer, align 1
; CHECK: @b = common global [32 x i8] zeroinitializer, align 1
; CHECK: @str = private unnamed_addr constant [32 x i8] c"hello\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00", align 1
; CHECK: @str.1 = private unnamed_addr constant [32 x i8] c"hello\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00", align 1
; CHECK: @str.2 = private unnamed_addr constant [8 x i8] c"hello\00\00\00", align 1
;.
define i32 @test_simplify1() {
; CHECK-LABEL: @test_simplify1(
; CHECK-NEXT: [[TARGET:%.*]] = alloca [1024 x i8], align 1
; CHECK-NEXT: store i8 0, ptr [[TARGET]], align 1
; CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr noundef nonnull align 1 dereferenceable(6) [[TARGET]], ptr noundef nonnull align 1 dereferenceable(6) @hello, i32 6, i1 false)
; CHECK-NEXT: call void @llvm.memset.p0.i32(ptr noundef nonnull align 1 dereferenceable(42) [[TARGET]], i8 0, i32 42, i1 false)
; CHECK-NEXT: call void @llvm.memset.p0.i32(ptr noundef nonnull align 1 dereferenceable(42) [[TARGET]], i8 0, i32 42, i1 false)
; CHECK-NEXT: [[TMP1:%.*]] = call i32 @puts(ptr noundef nonnull dereferenceable(1) [[TARGET]])
; CHECK-NEXT: ret i32 0
;
%target = alloca [1024 x i8]
store i8 0, ptr %target
%rslt1 = call ptr @strncpy(ptr %target, ptr @hello, i32 6)
%rslt2 = call ptr @strncpy(ptr %rslt1, ptr @null, i32 42)
%rslt3 = call ptr @strncpy(ptr %rslt2, ptr @null_hello, i32 42)
call i32 @puts( ptr %rslt3 )
ret i32 0
}
; Check strncpy(x, "", y) -> memset(x, '\0', y, 1).
define void @test_simplify2() {
; CHECK-LABEL: @test_simplify2(
; CHECK-NEXT: call void @llvm.memset.p0.i32(ptr noundef nonnull align 1 dereferenceable(32) @a, i8 0, i32 32, i1 false)
; CHECK-NEXT: ret void
;
call ptr @strncpy(ptr @a, ptr @null, i32 32)
ret void
}
; Check strncpy(x, y, 0) -> x.
define ptr @test_simplify3() {
; CHECK-LABEL: @test_simplify3(
; CHECK-NEXT: ret ptr @a
;
%ret = call ptr @strncpy(ptr @a, ptr @hello, i32 0)
ret ptr %ret
}
; Check strncpy(x, s, c) -> memcpy(x, s, c, 1) [s and c are constant].
define void @test_simplify4() {
; CHECK-LABEL: @test_simplify4(
; CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr noundef nonnull align 1 dereferenceable(6) @a, ptr noundef nonnull align 1 dereferenceable(6) @hello, i32 6, i1 false)
; CHECK-NEXT: ret void
;
call ptr @strncpy(ptr @a, ptr @hello, i32 6)
ret void
}
define void @test_simplify5(ptr %dst) {
; CHECK-LABEL: @test_simplify5(
; CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr noundef nonnull align 1 dereferenceable(32) [[DST:%.*]], ptr noundef nonnull align 1 dereferenceable(32) @str, i32 32, i1 false)
; CHECK-NEXT: ret void
;
call ptr @strncpy(ptr dereferenceable(8) %dst, ptr @hello, i32 32)
ret void
}
define void @test_simplify6(ptr %dst) {
; CHECK-LABEL: @test_simplify6(
; CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr noundef nonnull align 1 dereferenceable(80) [[DST:%.*]], ptr noundef nonnull align 1 dereferenceable(32) @str.1, i32 32, i1 false)
; CHECK-NEXT: ret void
;
call ptr @strncpy(ptr dereferenceable(80) %dst, ptr @hello, i32 32)
ret void
}
define void @test_simplify7(ptr %dst, i32 %n) {
; CHECK-LABEL: @test_simplify7(
; CHECK-NEXT: call void @llvm.memset.p0.i32(ptr align 1 dereferenceable(80) [[DST:%.*]], i8 0, i32 [[N:%.*]], i1 false)
; CHECK-NEXT: ret void
;
; Unless N is known to be nonzero, strncpy(D, "", N) need not access any
; bytes in D.
; TODO: The argument, already annotated dereferenceable, should be
; annotated noundef and nonnull by the transformation. See
; https://reviews.llvm.org/D124633.
call ptr @strncpy(ptr dereferenceable(80) %dst, ptr @null, i32 %n)
ret void
}
define ptr @test1(ptr %dst, ptr %src, i32 %n) {
; CHECK-LABEL: @test1(
; CHECK-NEXT: [[RET:%.*]] = call ptr @strncpy(ptr nonnull [[DST:%.*]], ptr nonnull [[SRC:%.*]], i32 [[N:%.*]])
; CHECK-NEXT: ret ptr [[RET]]
;
; Unless N is known to be nonzero, strncpy(D, S, N) need not access any
; bytes in either D or S. Verify that the call isn't annotated with
; the dereferenceable attribute.
; TODO: Both arguments should be annotated noundef in addition to nonnull.
; See https://reviews.llvm.org/D124633.
%ret = call ptr @strncpy(ptr nonnull %dst, ptr nonnull %src, i32 %n)
ret ptr %ret
}
define ptr @test2(ptr %dst) {
; CHECK-LABEL: @test2(
; CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr noundef nonnull align 1 dereferenceable(5) [[DST:%.*]], ptr noundef nonnull align 1 dereferenceable(6) @hello, i32 5, i1 false)
; CHECK-NEXT: ret ptr [[DST]]
;
%ret = call ptr @strncpy(ptr nonnull %dst, ptr nonnull @hello, i32 5)
ret ptr %ret
}
define ptr @test3(ptr %dst, i32 %n) {
; CHECK-LABEL: @test3(
; CHECK-NEXT: call void @llvm.memset.p0.i32(ptr noalias noundef nonnull align 1 dereferenceable(5) [[DST:%.*]], i8 0, i32 5, i1 false)
; CHECK-NEXT: ret ptr [[DST]]
;
%ret = call ptr @strncpy(ptr noalias nonnull %dst, ptr nonnull @null, i32 5);
ret ptr %ret
}
define ptr @test4(ptr %dst, i32 %n) {
; CHECK-LABEL: @test4(
; CHECK-NEXT: call void @llvm.memset.p0.i32(ptr noalias noundef nonnull align 16 dereferenceable(5) [[DST:%.*]], i8 0, i32 5, i1 false)
; CHECK-NEXT: ret ptr [[DST]]
;
%ret = call ptr @strncpy(ptr align(16) noalias nonnull %dst, ptr nonnull @null, i32 5);
ret ptr %ret
}
; Check cases that shouldn't be simplified.
define void @test_no_simplify1() {
; CHECK-LABEL: @test_no_simplify1(
; CHECK-NEXT: [[TMP1:%.*]] = call ptr @strncpy(ptr noundef nonnull dereferenceable(1) @a, ptr noundef nonnull dereferenceable(1) @b, i32 32)
; CHECK-NEXT: ret void
;
call ptr @strncpy(ptr @a, ptr @b, i32 32)
ret void
}
define void @test_no_simplify2() {
; CHECK-LABEL: @test_no_simplify2(
; CHECK-NEXT: store i64 478560413032, ptr @a, align 1
; CHECK-NEXT: ret void
;
call ptr @strncpy(ptr @a, ptr @hello, i32 8)
ret void
}
define ptr @test_no_simplify3(ptr %dst, ptr %src, i32 %count) {
; CHECK-LABEL: @test_no_simplify3(
; CHECK-NEXT: [[RET:%.*]] = musttail call ptr @strncpy(ptr [[DST:%.*]], ptr [[SRC:%.*]], i32 32)
; CHECK-NEXT: ret ptr [[RET]]
;
%ret = musttail call ptr @strncpy(ptr %dst, ptr %src, i32 32)
ret ptr %ret
}
define ptr @test_no_simplify4(ptr %dst, ptr %src, i32 %count) {
; CHECK-LABEL: @test_no_simplify4(
; CHECK-NEXT: [[RET:%.*]] = musttail call ptr @strncpy(ptr [[DST:%.*]], ptr [[SRC:%.*]], i32 6)
; CHECK-NEXT: ret ptr [[RET]]
;
%ret = musttail call ptr @strncpy(ptr %dst, ptr %src, i32 6)
ret ptr %ret
}
define void @test_no_incompatible_attr() {
; CHECK-LABEL: @test_no_incompatible_attr(
; CHECK-NEXT: call void @llvm.memcpy.p0.p0.i32(ptr noundef nonnull align 1 dereferenceable(6) @a, ptr noundef nonnull align 1 dereferenceable(6) @hello, i32 6, i1 false)
; CHECK-NEXT: ret void
;
call ptr @strncpy(ptr @a, ptr @hello, i32 6)
ret void
}
;.
; CHECK: attributes #[[ATTR0:[0-9]+]] = { nocallback nofree nounwind willreturn memory(argmem: readwrite) }
; CHECK: attributes #[[ATTR1:[0-9]+]] = { nocallback nofree nounwind willreturn memory(argmem: write) }
;.
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