The PowerPC vector-pack instructions are defined architecturally with
a big-endian bias, in that the vector element numbering is assumed to
be "left to right" regardless of whether the processor is in
big-endian or little-endian mode. This definition is unnatural for
little-endian code generation.
To facilitate ease of porting, the vec_pack and related interfaces are
designed to use natural element ordering, so that elements are
numbered according to little-endian design principles when code is
generated for a little-endian target. The vec_pack calls are
implemented as calls to vec_perm, specifying selection of the
odd-numbered vector elements. For little endian, this means the
odd-numbered elements counting from the right end of the register.
Since the underlying instructions count from the left end, we must
instead select the even-numbered vector elements for little endian to
achieve the desired semantics.
The correctness of this code is tested by the new pack.c test added in
a previous patch. I plan to later make the existing ppc32 Altivec
compile-time tests work for ppc64 and ppc64le as well.
llvm-svn: 210340
The PowerPC vector-multiply-even and vector-multiply-odd instructions
are defined architecturally with a big-endian bias, in that the vector
element numbering is assumed to be "left to right" regardless of
whether the processor is in big-endian or little-endian mode. This
definition is unnatural for little-endian code generation.
To facilitate ease of porting, the vec_mule and vec_mulo interfacs are
designed to use natural element ordering, so that elements are
numbered according to little-endian design principles when code is
generated for a little-endian target. The desired semantics can be
achieved by using the opposite instruction for little-endian mode.
That is, when a call to vec_mule appears in the code, a
vector-multiply-odd is generated, and when a call to vec_mulo appears
in the code, a vector-multiply-even is generated.
The correctness of this code is tested by the new mult-even-odd.c test
added in a previous patch. I plan to later make the existing ppc32
Altivec compile-time tests work for ppc64 and ppc64le as well.
llvm-svn: 210337
This patch fixes a couple of lowering issues for little endian
PowerPC. The code for lowering BUILD_VECTOR contains a number of
optimizations that are only valid for big endian. For now, we disable
those optimizations for correctness. In the future, we will add
analogous optimizations that are correct for little endian.
When lowering a SHUFFLE_VECTOR to a VPERM operation, we again need to
make the now-familiar transformation of swapping the input operands
and complementing the permute control vector. Correctness of this
transformation is tested by the accompanying test case.
llvm-svn: 210336
Before (JavaScript example, but can extend to other languages):
return {
a: 'E',
b: function() {
return function() {
f(); // This is wrong.
};
}
};
After:
return {
a: 'E',
b: function() {
return function() {
f(); // This is better.
};
}
};
llvm-svn: 210334
A leftover -S was generating unwanted output in the source tree overriding
-only flags that normally disable output.
This reverts commit r210323 and implements the proper fix.
Reported by Timur Iskhodzhanov!
llvm-svn: 210326
We probably just need to touch LLVM's configure this time to work around the
totally inadequate Makefile build server integration.
This reverts commit r210314.
llvm-svn: 210320
r210177 added lld Makefiles, r210245 added automatic build when the source is present.
This revision completes the set by adding the lld test and unittests to the check-all target.
llvm-svn: 210318
This will unbreak clang vendor builds as a follow-up to r210238, now that we
can't poke into LLVM's private config.h (nor should the string be exposed by
llvm-config.h).
This hopefully removes for good the last include of LLVM's config.h.
llvm-svn: 210313
The option check was being performed after config.h/llvm-config.h substitution,
generating incorrect macro definitions.
Fixes PR19614.
llvm-svn: 210311
If we have common uses on separate paths in the tree; process the one with greater common depth first.
This makes sure that we do not assume we need to extract a load when it is actually going to be part of a vectorized tree.
Review: http://reviews.llvm.org/D3800
llvm-svn: 210310
clang's own CMake setup handles this as of r210308.
The CMAKE_CROSSCOMPILING special-case will no longer be hard-coded. This was
clearly site-specific to someone's local configuration and should be passed in
at configure time if needed with e.g. -DLIBXML2_LIBRARIES=... (the libxml2
target I tried here doesn't even support liblzma so it's *way* off).
llvm-svn: 210309
Alias with unnamed_addr were in a strange state. It is stored in GlobalValue,
the language reference talks about "unnamed_addr aliases" but the verifier
was rejecting them.
It seems natural to allow unnamed_addr in aliases:
* It is a property of how it is accessed, not of the data itself.
* It is perfectly possible to write code that depends on the address
of an alias.
This patch then makes unname_addr legal for aliases. One side effect is that
the syntax changes for a corner case: In globals, unnamed_addr is now printed
before the address space.
llvm-svn: 210302
We extended the .section syntax to allow multiple sections with the
same name but different comdats, but currently we don't make sure that
the output section has that comdat symbol.
That happens to work with the code llc produces currently because it looks like
.section secName, "dr", one_only, "COMDATSym"
.globl COMDATSym
COMDATSym:
....
but that is not very friendly to anyone coding in assembly or even to
llc once we get comdat support in the IR.
This patch changes the coff object writer to make sure the comdat symbol is
output just after the section symbol, as required by the coff spec.
llvm-svn: 210298
Chandler correctly pointed out that I need an LLVM IR test for
r210282, which modified the vperm -> shuffle transform for little
endian PowerPC. This patch provides that test.
llvm-svn: 210297
Dmitry Vyukov