llvm-mirror/test/Transforms/InstCombine/pr43081.ll
Dimitry Andric f4ae71aa6d Check result of emitStrLen before passing it to CreateGEP
Summary:
This fixes PR43081, where the transformation of `strchr(p, 0) -> p +
strlen(p)` can cause a segfault, if `-fno-builtin-strlen` is used.  In
that case, `emitStrLen` returns nullptr, which CreateGEP is not designed
to handle.  Also add the minimized code from the PR as a test case.

Reviewers: xbolva00, spatel, jdoerfert, efriedma

Reviewed By: efriedma

Subscribers: lebedev.ri, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D70143
2019-11-14 08:04:36 +01:00

16 lines
504 B
LLVM

; RUN: opt < %s -instcombine -disable-builtin strlen -S | FileCheck %s
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"
declare i8* @strchr(i8*, i32)
define i8* @pr43081(i8* %a) {
entry:
%a.addr = alloca i8*, align 8
store i8* %a, i8** %a.addr, align 8
%0 = load i8*, i8** %a.addr, align 8
%call = call i8* @strchr(i8* %0, i32 0)
ret i8* %call
; CHECK: call i8* @strchr
}