This patch adds a new common code feature that allows platform code to
request minimum alignment of global symbols. The background for this is
that on SystemZ, the most efficient way to load addresses of global symbol
is the LOAD ADDRESS RELATIVE LONG (LARL) instruction. This instruction
provides PC-relative addressing, but only to *even* addresses. For this
reason, existing compilers will guarantee that global symbols are always
aligned to at least 2. [ Since symbols would otherwise already use a
default alignment based on their type, this will usually only affect global
objects of character type or character arrays. ] GCC also allows creating
symbols without that extra alignment by using explicit "aligned" attributes
(which then need to be used on both definition and each use of the symbol).
To enable support for this with Clang, this patch adds a
TargetInfo::MinGlobalAlign variable that provides a global minimum for the
alignment of every global object (unless overridden via explicit alignment
attribute), and adds code to respect this setting. Within this patch, no
platform actually sets the value to anything but the default 1, resulting
in no change in behaviour on any existing target.
This version of the patch incorporates feedback from reviews by
Eric Christopher and John McCall. Thanks to all reviewers!
Patch by Richard Sandiford.
llvm-svn: 181210
uncovered.
This required manually correcting all of the incorrect main-module
headers I could find, and running the new llvm/utils/sort_includes.py
script over the files.
I also manually added quite a few missing headers that were uncovered by
shuffling the order or moving headers up to be main-module-headers.
llvm-svn: 169237
AVX). Currently, if no aligned attribute is specified the alignment of a vector is
inferred from its size. Thus, very large vectors will be over-aligned with no
benefit. Target owners should set this target max.
llvm-svn: 160209
This is equal to alignof(std::max_align_t) on the platform and equal to the
alignment provided by malloc. (Platform owners please double-check your
platform's value.)
llvm-svn: 146762
alignment. This fixes cases where the anonymous bitfield is followed by a
non-bitfield member. E.g.,
struct t4
{
int foo : 1;
long : 0;
char bar;
};
Part of rdar://9859156
llvm-svn: 136858
which versions of an OS provide a certain facility. For example,
void foo()
__attribute__((availability(macosx,introduced=10.2,deprecated=10.4,obsoleted=10.6)));
says that the function "foo" was introduced in 10.2, deprecated in
10.4, and completely obsoleted in 10.6. This attribute ties in with
the deployment targets (e.g., -mmacosx-version-min=10.1 specifies that
we want to deploy back to Mac OS X 10.1). There are several concrete
behaviors that this attribute enables, as illustrated with the
function foo() above:
- If we choose a deployment target >= Mac OS X 10.4, uses of "foo"
will result in a deprecation warning, as if we had placed
attribute((deprecated)) on it (but with a better diagnostic)
- If we choose a deployment target >= Mac OS X 10.6, uses of "foo"
will result in an "unavailable" warning (in C)/error (in C++), as
if we had placed attribute((unavailable)) on it
- If we choose a deployment target prior to 10.2, foo() is
weak-imported (if it is a kind of entity that can be weak
imported), as if we had placed the weak_import attribute on it.
Naturally, there can be multiple availability attributes on a
declaration, for different platforms; only the current platform
matters when checking availability attributes.
The only platforms this attribute currently works for are "ios" and
"macosx", since we already have -mxxxx-version-min flags for them and we
have experience there with macro tricks translating down to the
deprecated/unavailable/weak_import attributes. The end goal is to open
this up to other platforms, and even extension to other "platforms"
that are really libraries (say, through a #pragma clang
define_system), but that hasn't yet been designed and we may want to
shake out more issues with this narrower problem first.
Addresses <rdar://problem/6690412>.
As a drive-by bug-fix, if an entity is both deprecated and
unavailable, we only emit the "unavailable" diagnostic.
llvm-svn: 128127
add support for the OpenCL __private, __local, __constant and
__global address spaces, as well as the __read_only, _read_write and
__write_only image access specifiers. Patch originally by ARM;
language-specific address space support by myself.
llvm-svn: 127915
Fix the width and align of bool type on Darwin to be 32bits
while keeping it 8 everywhere else.
Change the definition of va_list to default to SV4 ABI one
and let darwin subtarget override this.
Both changes submitted by Nathan Whitehorn and reviewed
by Rafael Espindola.
llvm-svn: 122956
16-bits in size. Implement this by splitting WChar into two enums, like we have
for char. This fixes a miscompmilation of XULRunner, PR8856.
llvm-svn: 122558
whether to use objc_msgSend_fpret; the choice is target dependent, not Obj-C ABI
dependent.
- <rdar://problem/8139758> arm objc _objc_msgSend_fpret bug
llvm-svn: 108379
- Used to determine whether the alignment of the type in a bit-field is
respected when laying out structures. The default is true, targets can
override this as needed.
- This is designed to correspond to the PCC_BITFIELD_TYPE_MATTERS macro in
gcc. The AST/Sema implementation only affects one line, unless I have
forgotten something. I'd appreciate further review.
- IRgen still needs to be updated to fully support this (which is effectively
PR5591).
llvm-svn: 101356
Ulrich Weigand