As the pairing of this instruction form with the bdnz/bdz branches is now
enforced by the verification pass, make it clear from the name that these
are used only for counter-based loops.
No functionality change intended.
llvm-svn: 182296
When asserts are enabled, this adds a verification pass for PPC counter-loop
formation. Unfortunately, without sacrificing code quality, there is no better
way of forming counter-based loops except at the (late) IR level. This means
that we need to recognize, at the IR level, anything which might turn into a
function call (or indirect branch). Because this is currently a finite set of
things, and because SelectionDAG lowering is basic-block local, this can be
done. Nevertheless, it is fragile, and failure results in a miscompile. This
verification pass checks that all (reachable) counter-based branches are
dominated by a loop mtctr instruction, and that no instructions in between
clobber the counter register. If these conditions are not satisfied, then an
ICE will be triggered.
In short, this is to help us sleep better at night.
llvm-svn: 182295
R600TextureIntrinsicsReplacer.cpp:232: warning: the address of ‘ArgsType’ will always evaluate as ‘true’
This doesn't have any effect on the output as a vararg intrinsic behaves the
same way as a non-vararg one.
llvm-svn: 182293
Before this change, the SystemZ backend would use BRCL for all branches
and only consider shortening them to BRC when generating an object file.
E.g. a branch on equal would use the JGE alias of BRCL in assembly output,
but might be shortened to the JE alias of BRC in ELF output. This was
a useful first step, but it had two problems:
(1) The z assembler isn't traditionally supposed to perform branch shortening
or branch relaxation. We followed this rule by not relaxing branches
in assembler input, but that meant that generating assembly code and
then assembling it would not produce the same result as going directly
to object code; the former would give long branches everywhere, whereas
the latter would use short branches where possible.
(2) Other useful branches, like COMPARE AND BRANCH, do not have long forms.
We would need to do something else before supporting them.
(Although COMPARE AND BRANCH does not change the condition codes,
the plan is to model COMPARE AND BRANCH as a CC-clobbering instruction
during codegen, so that we can safely lower it to a separate compare
and long branch where necessary. This is not a valid transformation
for the assembler proper to make.)
This patch therefore moves branch relaxation to a pre-emit pass.
For now, calls are still shortened from BRASL to BRAS by the assembler,
although this too is not really the traditional behaviour.
The first test takes about 1.5s to run, and there are likely to be
more tests in this vein once further branch types are added. The feeling
on IRC was that 1.5s is a bit much for a single test, so I've restricted
it to SystemZ hosts for now.
The patch exposes (and fixes) some typos in the main CodeGen/SystemZ tests.
A later patch will remove the {{g}}s from that directory.
llvm-svn: 182274
While the C++ standard requires that this lookup take place only at the
definition point of a virtual destructor (C++11 [class.dtor]p12), the
Microsoft ABI may require the compiler to emit a deleting destructor
for any virtual destructor declared in the TU, including ones without
a body, requiring an operator delete() lookup for every virtual
destructor declaration. The result of the lookup should be the same
no matter which declaration is used (except in weird corner cases).
This change will cause us to reject some valid TUs in Microsoft ABI
mode, e.g.:
struct A {
void operator delete(void *);
};
struct B {
void operator delete(void *);
};
struct C : A, B {
virtual ~C();
};
As Richard points out, every virtual function declared in a TU
(including this virtual destructor) is odr-used, so it must be defined
in any program which declares it, or the program is ill formed, no
diagnostic required. Because we know that any definition of this
destructor will cause the lookup to fail, the compiler can choose to
issue a diagnostic here.
Differential Revision: http://llvm-reviews.chandlerc.com/D822
llvm-svn: 182270
selectany only applies to externally visible global variables. It has
the effect of making the data weak_odr.
The MSDN docs suggest that unused definitions can only be dropped at
linktime, so Clang uses weak instead of linkonce. MSVC optimizes away
references to constant selectany data, so it must assume that there is
only one definition, hence weak_odr.
Reviewers: espindola
Differential Revision: http://llvm-reviews.chandlerc.com/D814
llvm-svn: 182266
As the namings of the scops have changed, polly was not able to read in the user
given .jscop files. By renaming the provided files, polly now finds them again
and can use them to optimize the matmul function. We also update the generated
files to reflect the very latest version of Polly.
llvm-svn: 182265
This converter currently only handles global variables in address space 0. For
these variables, they are promoted to address space 1 (global memory), and all
uses are updated to point to the result of a cvta.global instruction on the new
variable.
The motivation for this is address space 0 global variables are illegal since we
cannot declare variables in the generic address space. Instead, we place the
variables in address space 1 and explicitly convert the pointer to address
space 0. This is primarily intended to help new users who expect to be able to
place global variables in the default address space.
llvm-svn: 182254
Introduction:
In case when stack alignment is 8 and GPRs parameter part size is not N*8:
we add padding to GPRs part, so part's last byte must be recovered at
address K*8-1.
We need to do it, since remained (stack) part of parameter starts from
address K*8, and we need to "attach" "GPRs head" without gaps to it:
Stack:
|---- 8 bytes block ----| |---- 8 bytes block ----| |---- 8 bytes...
[ [padding] [GPRs head] ] [ ------ Tail passed via stack ------ ...
FIX:
Note, once we added padding we need to correct *all* Arg offsets that are going
after padded one. That's why we need this fix: Arg offsets were never corrected
before this patch. See new test-cases included in patch.
We also don't need to insert padding for byval parameters that are stored in GPRs
only. We need pad only last byval parameter and only in case it outsides GPRs
and stack alignment = 8.
Though, stack area, allocated for recovered byval params, must satisfy
"Size mod 8 = 0" restriction.
This patch reduces stack usage for some cases:
We can reduce ArgRegsSaveArea since inner N*4 bytes sized byval params my be
"packed" with alignment 4 in some cases.
llvm-svn: 182237