In r227480, Ulrich Weigand introduced a workaround for a linker
optimization bug that can create mis-optimized code for accesses to
general-dynamic or local-dynamic TLS variables. The linker
optimization bug only occurred for Clang/LLVM because of some
inefficient code being generated for these TLS accesses. I have
recently corrected LLVM to produce the efficient code sequence
expected by the linkers, so this workaround is no longer needed.
Therefore this patch reverts r227480.
I've tested that the previous bootstrap failure no longer occurs with
the workaround reverted.
llvm-svn: 228253
Work around a bug in GNU ld (and gold) linker versions up to 2.25
that may mis-optimize code generated by this version of clang/LLVM
to access general-dynamic or local-dynamic TLS variables.
Bug is fixed here:
https://sourceware.org/ml/binutils/2015-01/msg00318.html
llvm-svn: 227480
The PPC backend will now assume that PPC64 ELFv1 function descriptors are
invariant. This must be true for well-defined C/C++ code, but I'm providing an
option to disable this assumption in case someone's JIT-engine needs it.
llvm-svn: 226209
The current VSX feature for PowerPC specifies availability of the VSX
instructions added with the 2.06 architecture version. With 2.07, the
architecture adds new instructions to both the Category:Vector and
Category:VSX instruction sets. Additionally, unaligned vector storage
operations have improved performance.
This patch adds a feature to provide access to the new instructions
and performance capabilities of Power8. For compatibility with GCC,
the feature is controlled via a new -mpower8-vector switch, and the
feature causes the __POWER8_VECTOR__ builtin define to be generated by
the preprocessor.
There is a companion patch for llvm being committed at the same time.
llvm-svn: 219502
This patch provides basic support for powerpc64le as an LLVM target.
However, use of this target will not actually generate little-endian
code. Instead, use of the target will cause the correct little-endian
built-in defines to be generated, so that code that tests for
__LITTLE_ENDIAN__, for example, will be correctly parsed for
syntax-only testing. Code generation will otherwise be the same as
powerpc64 (big-endian), for now.
The patch leaves open the possibility of creating a little-endian
PowerPC64 back end, but there is no immediate intent to create such a
thing.
The new test case variant ensures that correct built-in defines for
little-endian code are generated.
llvm-svn: 187180
gcc provides -mmfcrf and -mno-mfcrf for controlling what we call
the mfocrf target feature. Also, PPC is now making use of the
static function AddTargetFeature used by the Mips Driver code.
llvm-svn: 178227