Commit Graph

6 Commits

Author SHA1 Message Date
Tim Northover 228d9d3aa2 Implement external weak (ELF) symbols on AArch64
Weakly defined symbols should evaluate to 0 if they're undefined at
link-time. This is impossible to do with the usual address generation
patterns, so we should use a literal pool entry to materlialise the
address.

llvm-svn: 174518
2013-02-06 16:43:33 +00:00
Owen Anderson de89ecf1fc Reapply r174343, with a fix for a scary DAG combine bug where it failed to differentiate between the alignment of the
base point of a load, and the overall alignment of the load.  This caused infinite loops in DAG combine with the
original application of this patch.

ORIGINAL COMMIT LOG:
When the target-independent DAGCombiner inferred a higher alignment for a load,
it would replace the load with one with the higher alignment.  However, it did
not place the new load in the worklist, which prevented later DAG combines in
the same phase (for example, target-specific combines) from ever seeing it.

This patch corrects that oversight, and updates some tests whose output changed
due to slightly different DAGCombine outputs.

llvm-svn: 174431
2013-02-05 19:24:39 +00:00
NAKAMURA Takumi 3753b28cd2 Revert r174343, "When the target-independent DAGCombiner inferred a higher alignment for a load,"
It caused hangups in compiling clang/lib/Parse/ParseDecl.cpp and clang/lib/Driver/Tools.cpp in stage2 on some hosts.

llvm-svn: 174374
2013-02-05 14:44:16 +00:00
Owen Anderson a47fdbb032 When the target-independent DAGCombiner inferred a higher alignment for a load,
it would replace the load with one with the higher alignment.  However, it did
not place the new load in the worklist, which prevented later DAG combines in
the same phase (for example, target-specific combines) from ever seeing it.

This patch corrects that oversight, and updates some tests whose output changed
due to slightly different DAGCombine outputs.

llvm-svn: 174343
2013-02-05 06:25:30 +00:00
Tim Northover e3d4236402 Add explicit triples to AArch64 tests
Only Linux is supported at the moment, and other platforms quickly fault. As a
result these tests would fail on non-Linux hosts. It may be worth making the
tests more generic again as more platforms are supported.

llvm-svn: 174170
2013-02-01 11:40:47 +00:00
Tim Northover e0e3aefdd3 Add AArch64 as an experimental target.
This patch adds support for AArch64 (ARM's 64-bit architecture) to
LLVM in the "experimental" category. Currently, it won't be built
unless requested explicitly.

This initial commit should have support for:
    + Assembly of all scalar (i.e. non-NEON, non-Crypto) instructions
      (except the late addition CRC instructions).
    + CodeGen features required for C++03 and C99.
    + Compilation for the "small" memory model: code+static data <
      4GB.
    + Absolute and position-independent code.
    + GNU-style (i.e. "__thread") TLS.
    + Debugging information.

The principal omission, currently, is performance tuning.

This patch excludes the NEON support also reviewed due to an outbreak of
batshit insanity in our legal department. That will be committed soon bringing
the changes to precisely what has been approved.

Further reviews would be gratefully received.

llvm-svn: 174054
2013-01-31 12:12:40 +00:00