Test case by Michele Scandale!
Fixes PR10293: Load not hoisted out of loop with multiple exits.
There are few regressions with this patch, now tracked by
rdar:13817079, and a roughly equal number of improvements. The
regressions are almost certainly back luck because LoopRotate has very
little idea of whether rotation is profitable. Doing better requires a
more comprehensive solution.
This checkin is a quick fix that lacks generality (PR10293 has
a counter-example). But it trivially fixes the case in PR10293 without
interfering with other cases, and it does satify the criteria that
LoopRotate is a loop canonicalization pass that should avoid
heuristics and special cases.
I can think of two approaches that would probably be better in
the long run. Ultimately they may both make sense.
(1) LoopRotate should check that the current header would make a good
loop guard, and that the loop does not already has a sufficient
guard. The artifical SimplifiedLoopLatch check would be unnecessary,
and the design would be more general and canonical. Two difficulties:
- We need a strong guarantee that we won't endlessly rotate, so the
analysis would need to be precise in order to avoid the
SimplifiedLoopLatch precondition.
- Analysis like this are usually based on SCEV, which we don't want to
rely on.
(2) Rotate on-demand in late loop passes. This could even be done by
shoving the loop back on the queue after the optimization that needs
it. This could work well when we find LICM opportunities in
multi-branch loops. This requires some work, and it doesn't really
solve the problem of SCEV wanting a loop guard before the analysis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181230 91177308-0d34-0410-b5e6-96231b3b80d8
As pointed out by Rafael Espindola, we should match the DWARF encodings
produced by GCC in both pic and non-pic modes. This was not the case
for the non-pic case.
This patch changes all DWARF encodings to DW_EH_PE_absptr for the
non-pic case, just like GCC does. The test case is updated to check
for both variants.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181222 91177308-0d34-0410-b5e6-96231b3b80d8
A * (1 - (uitofp i1 C)) -> select C, 0, A
B * (uitofp i1 C) -> select C, B, 0
select C, 0, A + select C, B, 0 -> select C, B, A
These come up in code that has been hand-optimized from a select to a linear blend,
on platforms where that may have mattered. We want to undo such changes
with the following transform:
A*(1 - uitofp i1 C) + B*(uitofp i1 C) -> select C, A, B
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181216 91177308-0d34-0410-b5e6-96231b3b80d8
This patch finally enables the SystemZ target in the default build
(with --enable-targets=all).
Patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181209 91177308-0d34-0410-b5e6-96231b3b80d8
This patch wires up the SystemZ target in configure, so that it can now be
built using --enable-targets=systemz. It is not yet included in the default
build (--enable-targets=all); this will be done by a follow-up patch.
Patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181208 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds the necessary configuration bits and #ifdef's to set up
the JIT/MCJIT test cases for SystemZ. Like other recent targets, we do
fully support MCJIT, but do not support the old JIT at all. Set up the
lit config files accordingly, and disable old-JIT unit tests.
Patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181207 91177308-0d34-0410-b5e6-96231b3b80d8
This adds all DebugInfo tests for the SystemZ target.
This version of the patch incorporates feedback from reviews by
Eric Christopher and Rafael Espindola. Thanks to all reviewers!
Patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181205 91177308-0d34-0410-b5e6-96231b3b80d8
This adds all CodeGen tests for the SystemZ target.
This version of the patch incorporates feedback from a review by
Sean Silva. Thanks to all reviewers!
Patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181204 91177308-0d34-0410-b5e6-96231b3b80d8
This adds the actual lib/Target/SystemZ target files necessary to
implement the SystemZ target. Note that at this point, the target
cannot yet be built since the configure bits are missing. Those
will be provided shortly by a follow-on patch.
This version of the patch incorporates feedback from reviews by
Chris Lattner and Anton Korobeynikov. Thanks to all reviewers!
Patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181203 91177308-0d34-0410-b5e6-96231b3b80d8
This is another patch in preparation for adding the SystemZ target.
It defines the appropriate values for DWARF encodings; the intent
is to be compatible with what GCC currently does on the target.
Patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181201 91177308-0d34-0410-b5e6-96231b3b80d8
Several platforms need to disable all old-JIT unit tests, since they only
support the new MCJIT. This currently done via #ifdef'ing out those tests
in the ExecutionEngine/JIT/*.cpp files. As those #ifdef's have grown
historically, we now have a number of repeated directives which -in total-
cover nearly the whole file, but leave a couple of helper functions out.
When building the tests with clang itself, those helper functions now
cause spurious "unused function" warnings.
To fix those warnings, and also to remove the duplicate #ifdef conditions
and make it easier to disable the tests for a new target, this patch
consolidates the #ifdefs into a single one per file, which covers all
the tests including all helper routines.
Tested on PowerPC and SystemZ.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181200 91177308-0d34-0410-b5e6-96231b3b80d8
As pointed out by Evgeniy Stepanov, assigning a std::string temporary
to a StringRef is not a good idea. Rework MatchRegisterName to avoid
using the .lower routine.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181192 91177308-0d34-0410-b5e6-96231b3b80d8
Looks like symbol resolution is not working on cygwin, the test fails
because __gxx_personality_v0 is not found.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181179 91177308-0d34-0410-b5e6-96231b3b80d8
We used to disable constant merging not only if a constant is llvm.used, but
also if an alias of a constant is llvm.used. This change fixes that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181175 91177308-0d34-0410-b5e6-96231b3b80d8
This gets exception handling working on ELF and Macho (x86-64 at least).
Other than the EH frame registration, this patch also implements support
for GOT relocations which are used to locate the personality function on
MachO.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181167 91177308-0d34-0410-b5e6-96231b3b80d8
indirect branch at the end of the BB. Otherwise if-converter, branch folding
pass may incorrectly update its successor info if it consider BB as fallthrough
to the next BB.
rdar://13782395
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181161 91177308-0d34-0410-b5e6-96231b3b80d8
Instead operands are treated as negative immediates
where the sign bit is implicit in the instruction
encoding.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181151 91177308-0d34-0410-b5e6-96231b3b80d8
