Akira Hatanaka [Tue, 23 May 2017 06:08:37 +0000 (06:08 +0000)]
[AArch64] Fix PRR33100.
This commit fixes a bug introduced in r301019 where optimizeLogicalImm
would replace a logical node's immediate operand that was CSE'd and
was also an operand of another node.
This commit fixes the bug by replacing the logical node instead of its
immediate operand.
Teresa Johnson [Tue, 23 May 2017 00:08:00 +0000 (00:08 +0000)]
Support for taking the max of module flags when linking, use for PIE/PIC
Summary:
Add Max ModFlagBehavior, which can be used to take the max of two
module flag values when merging modules. Use it for the PIE and PIC
levels.
This avoids an error when we try to import from a module built -fpic
into a module built -fPIC, for example. For both PIE and PIC levels,
this will be legal, since the code generation gets more conservative
as the level is increased. Therefore we can take the max instead of
somehow trying to block importing between modules compiled with
different levels.
Craig Topper [Mon, 22 May 2017 23:50:40 +0000 (23:50 +0000)]
[InstSimplify] Fix the indentation throughout the interface header file.
The forward declarations and the SimplifyQuery class at the beginning of the namespace weren't indented. But the closing brace for SimplifyQuery and everything after it were indented.
This commit makes the whole file consistent to no identation per coding standards. The signature of every function in this file changed a few weeks ago so this isn't a big disturbance to the revision history.
Tim Northover [Mon, 22 May 2017 21:28:08 +0000 (21:28 +0000)]
InstructionSimplify: don't speculate about Constants changing.
When presented with an icmp/select pair, we can end up asking what would happen
if we replaced one constant with another in an instruction. This is a mistake,
while non-constant Values could become a constant, constants cannot change and
trying to do so can lead to completely invalid IR (a GEP referencing a
non-existant field in the original case).
Zachary Turner [Mon, 22 May 2017 21:07:43 +0000 (21:07 +0000)]
Implement various flavors of type merging.
Previous algotirhm assumed that types and ids are in a single
unified stream. For inputs that come from object files, this
is the case. But if the input is already a PDB, or is the result
of a previous merge, then the types and ids will already have
been split up, in which case we need an algorithm that can
accept operate on independent streams of types and ids that
refer across stream boundaries to each other.
Adrian Prantl [Mon, 22 May 2017 20:47:09 +0000 (20:47 +0000)]
Don't generate line&scope debug info for meta-instructions.
MachineInstructions that don't generate any code (such as
IMPLICIT_DEFs) should not generate any debug info either.
Fixes PR33107.
https://bugs.llvm.org/show_bug.cgi?id=33107
This reapplies r303566 without any modifications. The stage2 build
failures persisted even after reverting this patch, and looking back
through history, it looks like these tests are flaky.
Teresa Johnson [Mon, 22 May 2017 20:28:18 +0000 (20:28 +0000)]
Fix update VP metadata after inlining for instrumentation PGO
Summary:
With instrumentation profiling, when updating the VP metadata after
an inline, VP metadata on the inlined copy was inadvertantly having
all counts zeroed out. This was causing indirect calls from code inlined
during the call step to be marked as cold in the ThinLTO summaries and
not imported.
The CallerBFI needs to be passed down so that the CallSiteCount can be
computed from the profile summary info. With Sample PGO this was working
since the count is extracted from the branch weight metadata on the
call being inlined (even before we stopped looking at metadata for
non-sample PGO in r302844 this largely wasn't working for instrumentation
PGO since only promoted indirect calls would be getting inlined and have
the metadata).
Added an instrumentation PGO test and renamed the sample PGO test.
It's causing some buildbots to timeout whenever tablegen needs re-compilation,
particularly those with -fsanitize=memory but not only them. A compile time
regression was expected since it triples the amount of SelectionDAG rules we
are able to import but it's currently too high.
James Molloy [Mon, 22 May 2017 09:42:07 +0000 (09:42 +0000)]
Re-apply r302416: [ARM] Clear the constant pool cache on explicit .ltorg directives
Re-applying now that PR32825 which was raised on the commit this fixed up is now known to have also been fixed by this commit.
Original commit message:
Multiple ldr pseudoinstructions with the same constant value will
reuse the same constant pool entry. However, if the constant pool
is explicitly flushed with a .ltorg directive, we should not try
to reference constants in the previous pool any longer, since they
may be out of range.
This fixes assembling hand-written assembler source which repeatedly
loads the same constant value, across a binary size larger than the
pc-relative fixup range for ldr instructions (4096 bytes). Such
assembler source already uses explicit .ltorg instructions to emit
constant pools with regular intervals. However if we try to reuse
constants emitted in earlier pools, they end up out of range.
This makes the output of the testcase match what binutils gas does
(prior to this patch, it would fail to assemble).
David Blaikie [Mon, 22 May 2017 07:02:47 +0000 (07:02 +0000)]
libDebugInfo/DWARF: Apply relocations for debug_addr addresses in object files
llvm-symbolizer would fail to symbolize addresses in unlinked object
files when handling .dwo file data because the addresses would not be
relocated in the same way as the ranges in the skeleton CU in the object
file.
Fix that so object files can be symbolized the same as executables.
Sanjoy Das [Mon, 22 May 2017 06:46:04 +0000 (06:46 +0000)]
[SCEV] Clarify behavior around max backedge taken count
This is a re-application of a r303497 that was reverted in r303498.
I thought it had broken a bot when it had not (the breakage did not
go away with the revert).
This change makes the split between the "exact" backedge taken count
and the "maximum" backedge taken count a bit more obvious. Both of
these are upper bounds on the number of times the loop header
executes (since SCEV does not account for most kinds of abnormal
control flow), but the latter is guaranteed to be a constant.
There were a few places where the max backedge taken count *was* a
non-constant; I've changed those to compute constants instead.
At this point, I'm not sure if the constant max backedge count can be
computed by calling `getUnsignedRange(Exact).getUnsignedMax()` without
losing precision. If it can, we can simplify even further by making
`getMaxBackedgeTakenCount` a thin wrapper around
`getBackedgeTakenCount` and `getUnsignedRange`.
Igor Breger [Sun, 21 May 2017 11:13:56 +0000 (11:13 +0000)]
[GlobalISel][X86] Fix G_TRUNC instruction selection.
Updated tests with -verify-machineinstrs flag.
It fixes 3 tests failed with machine verifier enabled and listed
in PR27481
Hiroshi Inoue [Sun, 21 May 2017 06:00:05 +0000 (06:00 +0000)]
Summary
PPC backend eliminates compare instructions by using record-form instructions in PPCInstrInfo::optimizeCompareInstr, which is called from peephole optimization pass.
This patch improves this optimization to eliminate more compare instructions in two types of common case.
- comparison against a constant 1 or -1
The record-form instructions set CR bit based on signed comparison against 0. So, the current implementation does not exploit the record-form instruction for comparison against a non-zero constant.
This patch enables record-form optimization for constant of 1 or -1 if possible; it changes the condition "greater than -1" into "greater than or equal to 0" and "less than 1" into "less than or equal to 0".
With this patch, compare can be eliminated in the following code sequence, as an example.
uint64_t a, b;
if ((a | b) & 0x8000000000000000ull) { ... }
else { ... }
- andi for 32-bit comparison on PPC64
Since record-form instructions execute 64-bit signed comparison and so we have limitation in eliminating 32-bit comparison, i.e. with cmplwi, using the record-form. The original implementation already has such checks but andi. is not recognized as an instruction which executes implicit zero extension and hence safe to convert into record-form if used for equality check.
%1 = and i32 %a, 10
%2 = icmp ne i32 %1, 0
br i1 %2, label %foo, label %bar
In this simple example, LLVM generates andi. + cmplwi + beq on PPC64.
This patch make it possible to eliminate the cmplwi for this case.
I added andi. for optimization targets if it is safe to do so.
Sanjoy Das [Sun, 21 May 2017 01:47:50 +0000 (01:47 +0000)]
[SCEV] Clarify behavior around max backedge taken count
This change makes the split between the "exact" backedge taken count
and the "maximum" backedge taken count a bit more obvious. Both of
these are upper bounds on the number of times the loop header
executes (since SCEV does not account for most kinds of abnormal
control flow), but the latter is guaranteed to be a constant.
There were a few places where the max backedge taken count *was* a
non-constant; I've changed those to compute constants instead.
At this point, I'm not sure if the constant max backedge count can be
computed by calling `getUnsignedRange(Exact).getUnsignedMax()` without
losing precision. If it can, we can simplify even further by making
`getMaxBackedgeTakenCount` a thin wrapper around
`getBackedgeTakenCount` and `getUnsignedRange`.
Davide Italiano [Sat, 20 May 2017 00:46:54 +0000 (00:46 +0000)]
[NewGVN] Create a StoreExpression instead of a VariableExpression.
In the case where we have an operand defined by a lod of the
same memory location. Historically this was a VariableExpression
because we wanted to make sure they ended up in the same class,
but if we create the right expression, they end up in the same
class anyway.
Fixes PR32897. Thanks to Dan for the detailed discussion and the
fix suggestion.
Matthias Braun [Fri, 19 May 2017 22:37:09 +0000 (22:37 +0000)]
SimplifyLibCalls: Optimize wcslen
Refactor the strlen optimization code to work for both strlen and wcslen.
This especially helps with programs in the wild where people pass
L"string"s to const std::wstring& function parameters and the wstring
constructor gets inlined.
This also fixes a lingerind API problem/bug in getConstantStringInfo()
where zeroinitializers would always give you an empty string (without a
length) back regardless of the actual length of the initializer which
did not work well in the TrimAtNul==false causing the PR mentioned
below.
Note that the fixed getConstantStringInfo() needed fixes to SelectionDAG
memcpy lowering and may lead to some cases for out-of-bounds
zeroinitializer accesses not getting optimized anymore. So some code
with UB may produce out of bound memory reads now instead of just
producing zeros.
The refactoring "accidentally" fixes http://llvm.org/PR32124
Daniel Berlin [Fri, 19 May 2017 20:22:20 +0000 (20:22 +0000)]
NewGVN: Fix PR32838.
This is a complicated bug involving two issues:
1. What do we do with phi nodes when we prove all arguments are not
live?
2. When is it safe to use value leaders to determine if we can ignore
an argumnet?
Zachary Turner [Fri, 19 May 2017 19:26:58 +0000 (19:26 +0000)]
Resubmit "[CodeView] Provide a common interface for type collections."
This was originally reverted because it was a breaking a bunch
of bots and the breakage was not surfacing on Windows. After much
head-scratching this was ultimately traced back to a bug in the
lit test runner related to its pipe handling. Now that the bug
in lit is fixed, Windows correctly reports these test failures,
and as such I have finally (hopefully) fixed all of them in this
patch.
Daniel Berlin [Fri, 19 May 2017 19:01:27 +0000 (19:01 +0000)]
Last of the major pieces to NewGVN - yay!
Summary:
NewGVN: Handle equivalence between phi of ops and op of phis.
This makes our GVN mostly-complete. It would be complete, modulo some
deliberate choices we make. This means it detects roughly all herband
equivalences in polynomial time, including cases notoriously hard for
other GVN's to detect. It also detects a very large swath of the
cases we currently rely on instcombine to detect that involve folding
upwards through phis.
Amaury Sechet [Fri, 19 May 2017 18:20:44 +0000 (18:20 +0000)]
[DAGCombine] (addcarry 0, 0, X) -> (ext/trunc X)
Summary:
While this makes some case better and some case worse - so it's unclear if it is a worthy combine just by itself - this is a useful canonicalisation.
Zachary Turner [Fri, 19 May 2017 18:12:07 +0000 (18:12 +0000)]
[lit] Take the last error when executing pipelines.
This seems to have been present since the beginning of time,
which is quite surprising. The symptom was this: Suppose you
have a test with a run line that looks like this:
RUN: foo | FileCheck %s
foo prints some output and then due to a bug in the program it
asserts. On Windows this results in the program returning a
negative exit code. But if enough output had been printed
already by the tool so that the FileCheck match would succeed
then FileCheck would return 0, and because of bad logic in
lit this 0 return value would overwrite the failed return
value from previous items in the pipeline. This only happened
with negative exit codes.
The most sensible behavior is to just take whatever the first
exit code is. There is no logical ordering defined on exit
codes, so comparing with < and > does not make a lot of sense.
Instead, as soon as we find the first non-successful return
value, that should be the result of the entire expression.
This fixes the issue, as now tests which fail on non-Windows
platforms also fail for me on Windows as well.