mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-26 04:32:44 +01:00
9dbcbc0397
Summary: This change fixes an iterator wraparound bug in `determinePointerReadAttrs`. Ideally, ++'ing off the `end()` of an iplist should result in a failed assert, but currently iplist seems to silently wrap to the head of the list on `end()++`. This is why the bad behavior is difficult to demonstrate. Reviewers: chandlerc, reames Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D14350 llvm-svn: 252386
31 lines
1.1 KiB
LLVM
31 lines
1.1 KiB
LLVM
; RUN: opt -functionattrs -S < %s | FileCheck %s
|
|
|
|
; This checks for an iterator wraparound bug in FunctionAttrs. The previous
|
|
; "incorrect" behavior was inferring readonly for the %x argument in @caller.
|
|
; Inferring readonly for %x *is* actually correct, since @va_func is marked
|
|
; readonly, but FunctionAttrs was inferring readonly for the wrong reasons (and
|
|
; we _need_ the readonly on @va_func to trigger the problematic code path). It
|
|
; is possible that in the future FunctionAttrs becomes smart enough to infer
|
|
; readonly for %x for the right reasons, and at that point this test will have
|
|
; to be marked invalid.
|
|
|
|
declare void @llvm.va_start(i8*)
|
|
declare void @llvm.va_end(i8*)
|
|
|
|
define void @va_func(i32* readonly %b, ...) readonly nounwind {
|
|
; CHECK-LABEL: define void @va_func(i32* nocapture readonly %b, ...)
|
|
entry:
|
|
%valist = alloca i8
|
|
call void @llvm.va_start(i8* %valist)
|
|
call void @llvm.va_end(i8* %valist)
|
|
%x = call i32 @caller(i32* %b)
|
|
ret void
|
|
}
|
|
|
|
define i32 @caller(i32* %x) {
|
|
; CHECK-LABEL: define i32 @caller(i32* nocapture %x)
|
|
entry:
|
|
call void(i32*,...) @va_func(i32* null, i32 0, i32 0, i32 0, i32* %x)
|
|
ret i32 42
|
|
}
|