This pass was based on the previous (essentially unused) profiling
infrastructure and the assumption that by ordering the basic blocks at
the IR level in a particular way, the correct layout would happen in the
end. This sometimes worked, and mostly didn't. It also was a really
naive implementation of the classical paper that dates from when branch
predictors were primarily directional and when loop structure wasn't
commonly available. It also didn't factor into the equation
non-fallthrough branches and other machine level details.
Anyways, for all of these reasons and more, I wrote
MachineBlockPlacement, which completely supercedes this pass. It both
uses modern profile information infrastructure, and actually works. =]
llvm-svn: 190748
This was somewhat tricky because ~PrettyStackTraceEntry() may run after
llvm_shutdown() has been called. This is rare and only happens for a common idiom
used in the main() functions of command-line tools. This works around the idiom by
skipping the stack clean-up if the PrettyStackTraceHead ManagedStatic is not
constructed (i.e. llvm_shutdown() has been called).
llvm-svn: 190730
Implements Instruction scheduler latencies for Silvermont,
using latencies from the Intel Silvermont Optimization Guide.
Auto detects SLM.
Turns on post RA scheduler when generating code for SLM.
llvm-svn: 190717
By definition copies across register banks are not coalescable. Still, it may be
possible to get rid of such a copy when the value is available in another
register of the same register file.
Consider the following example, where capital and lower letters denote different
register file:
b = copy A <-- cross-bank copy
...
C = copy b <-- cross-bank copy
This could have been optimized this way:
b = copy A <-- cross-bank copy
...
C = copy A <-- same-bank copy
Note: b and C's definitions may be in different basic blocks.
This patch adds a peephole optimization that looks through a chain of copies
leading to a cross-bank copy and reuses a source that is on the same register
file if available.
This solution could also be used to get rid of some copies (e.g., A could have
been used instead of C). However, we do not do so because:
- It may over constrain the coloring of the source register for coalescing.
- The register allocator may not be able to find a nice split point for the
longer live-range, leading to more spill.
<rdar://problem/14742333>
llvm-svn: 190713
svn 1.8.0 emits an additional line matching 'URL:' in its 'svn info' command
('Relative URL:').
Changed the grep to match only the intended line so that a valid SVNVersion.inc
is generated.
The problem doesnt occur with the svn version I'm using (1.7.5) but Tobias has
confirmed that the change fixes the problem.
See http://llvm.org/bugs/show_bug.cgi?id=17203
llvm-svn: 190685
Since r187209, which modified ltdl.m4, I was unable to execute
AutoRegen.sh, getting:
../configure:10779: error: possibly undefined macro: AC_LTDL_FUNC_ARGZ
This commit re-adds AC_LTDL_FUNC_ARGZ to ltdl.m4, as a quick fix. For me, this
corresponds to the configure file currently checked in.
(However, the ltdl library seems to be unused since r74924 in 2009,
except for the use of the LTDL_SHLIB_EXT macro in
bugpoint(?). Therefore, the right solution seems to try to get rid of
the local ltdl.m4 file, specified by autoconf/README.TXT.)
llvm-svn: 190677
Previously we modelled VPR128 and VPR64 as essentially identical
register-classes containing V0-V31 (which had Q0-Q31 as "sub_alias"
sub-registers). This model is starting to cause significant problems
for code generation, particularly writing EXTRACT/INSERT_SUBREG
patterns for converting between the two.
The change here switches to classifying VPR64 & VPR128 as
RegisterOperands, which are essentially aliases for RegisterClasses
with different parsing and printing behaviour. This fits almost
exactly with their real status (VPR128 == FPR128 printed strangely,
VPR64 == FPR64 printed strangely).
llvm-svn: 190665
versions of gold. This support is designed to allow gold to produce
gdb_index sections similar to the accelerator tables and consumable
by gdb.
llvm-svn: 190649
When a structure is passed by value, and that structure contains a vector
member, according to the PPC ABI, the structure will receive enhanced alignment
(so that the vector within the structure will always be aligned).
This should resolve PR16641.
llvm-svn: 190636
Reviewed by Joe Abbey and Tobias Grosser
Here is a patch that fixes decoding of CE_SELECT in BitcodeReader,
along with a simple test case. The problem in the current code is that
it generates but doesn't accept bitcode that uses vectors for the
first element of a select in this context.
llvm-svn: 190634
In fast-math mode sqrt(x) is calculated using the fast expansion of the
reciprocal of the reciprocal sqrt expansion. The reciprocal and reciprocal
sqrt expansions use the associated estimate instructions along with some Newton
iterations. Unfortunately, as a result, sqrt(0) was being calculated as NaN,
which is not correct. Now we explicitly return a result of zero if the input is
zero.
llvm-svn: 190624
global ThreadLocals, thereby getting rid of the load-time initialization of those
objects and also getting rid of their destruction unless the LLVM client calls
llvm_shutdown.
llvm-svn: 190617
Add basic assembly/disassembly support for the first Intel SHA
instruction 'sha1rnds4'. Also includes feature flag, and test cases.
Support for the remaining instructions will follow in a separate patch.
llvm-svn: 190611
Use the new instruction deprecation feature to mark mftb (now replaced with
mfspr) and dst (along with the other Altivec cache control instructions) as
deprecated when targeting cores supporting at least ISA v2.03.
llvm-svn: 190605
