This changes IRCE to optimize uses, and not branches. This change is
NFCI since the uses we do inspect are in practice only ever going to be
the condition use in conditional branches; but this flexibility will
later allow us to analyze more complex expressions than just a direct
branch on a range check.
llvm-svn: 270500
When an aggregate contains an opaque type its size cannot be
determined. This triggers an "Invalid GetElementPtrInst indices for type" assert
in function checkGEPType. The fix suppresses the conversion in this case.
http://reviews.llvm.org/D20319
llvm-svn: 270479
Summary:
This patch turns on LoopUnrollAnalyzer by default. To mitigate compile
time regressions, I chose very conservative thresholds for now. Later we
can make them more aggressive, but it might require being smarter in
which loops we're optimizing. E.g. currently the biggest issue is that
with more agressive thresholds we unroll many cold loops, which
increases compile time for no performance benefit (performance of those
loops is improved, but it doesn't matter since they are cold).
Test results for compile time(using 4 samples to reduce noise):
```
MultiSource/Benchmarks/VersaBench/ecbdes/ecbdes 5.19%
SingleSource/Benchmarks/Polybench/medley/reg_detect/reg_detect 4.19%
MultiSource/Benchmarks/FreeBench/fourinarow/fourinarow 3.39%
MultiSource/Applications/JM/lencod/lencod 1.47%
MultiSource/Benchmarks/Fhourstones-3_1/fhourstones3_1 -6.06%
```
I didn't see any performance changes in the testsuite, but it improves
some internal tests.
Reviewers: hfinkel, chandlerc
Subscribers: llvm-commits, mzolotukhin
Differential Revision: http://reviews.llvm.org/D20482
llvm-svn: 270478
A cleanuppad is not cheap, they turn into many instructions and result
in additional spills and fills. It is not worth keeping a cleanuppad
around if all it does is hold a lifetime.end instruction.
N.B. We first try to merge the cleanuppad with another cleanuppad to
avoid dropping the lifetime and debug info markers.
llvm-svn: 270314
The InductiveRangeCheck struct is only five words long; so passing these
around value is fine. The allocator makes the code look more complex
than it is.
llvm-svn: 270309
I had used `std::remove_if` under the assumption that it moves the
predicate matching elements to the end, but actaully the elements
remaining towards the end (after the iterator returned by
`std::remove_if`) are indeterminate. Fix the bug (and make the code
more straightforward) by using a temporary SmallVector, and add a test
case demonstrating the issue.
llvm-svn: 270306
Summary:
Uses ModulePass instead of FunctionPass for EfficiencySanitizerPass to
better support global variable creation for a forthcoming struct field
counter tool.
Patch by Qin Zhao.
Reviewers: aizatsky
Subscribers: llvm-commits, eugenis, vitalybuka, bruening, kcc
Differential Revision: http://reviews.llvm.org/D20458
llvm-svn: 270263
Check that the incoming blocks of phi nodes are identical, and block
function merging if they are not.
rdar://problem/26255167
Differential Revision: http://reviews.llvm.org/D20462
llvm-svn: 270250
Sequences of range checks expressed using guards, like
guard((I - 2) u< L)
guard((I - 1) u< L)
guard((I + 0) u< L)
guard((I + 1) u< L)
guard((I + 2) u< L)
can sometimes be combined into a smaller sequence:
guard((I - 2) u< L AND (I + 2) u< L)
if we can prove that (I - 2) u< L AND (I + 2) u< L implies all of checks
expressed in the previous sequence.
This change teaches GuardWidening to do this kind of merging when
feasible.
llvm-svn: 270151
This patch fixes https://llvm.org/bugs/show_bug.cgi?id=27703.
If there is a sequence of one or more load instructions, each loaded value is used as address of later load instruction, bitcast is necessary to change the value type, don't optimize it.
llvm-svn: 270135
Transition InstrProf and Coverage over to the stricter Error/Expected
interface.
Changes since the initial commit:
- Fix error message printing in llvm-profdata.
- Check errors in loadTestingFormat() + annotateAllFunctions().
- Defer error handling in InstrProfIterator to InstrProfReader.
- Remove the base ProfError class to work around an MSVC ICE.
Differential Revision: http://reviews.llvm.org/D19901
llvm-svn: 270020
Summary:
Implement guard widening in LLVM. Description from GuardWidening.cpp:
The semantics of the `@llvm.experimental.guard` intrinsic lets LLVM
transform it so that it fails more often that it did before the
transform. This optimization is called "widening" and can be used hoist
and common runtime checks in situations like these:
```
%cmp0 = 7 u< Length
call @llvm.experimental.guard(i1 %cmp0) [ "deopt"(...) ]
call @unknown_side_effects()
%cmp1 = 9 u< Length
call @llvm.experimental.guard(i1 %cmp1) [ "deopt"(...) ]
...
```
to
```
%cmp0 = 9 u< Length
call @llvm.experimental.guard(i1 %cmp0) [ "deopt"(...) ]
call @unknown_side_effects()
...
```
If `%cmp0` is false, `@llvm.experimental.guard` will "deoptimize" back
to a generic implementation of the same function, which will have the
correct semantics from that point onward. It is always _legal_ to
deoptimize (so replacing `%cmp0` with false is "correct"), though it may
not always be profitable to do so.
NB! This pass is a work in progress. It hasn't been tuned to be
"production ready" yet. It is known to have quadriatic running time and
will not scale to large numbers of guards
Reviewers: reames, atrick, bogner, apilipenko, nlewycky
Subscribers: mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D20143
llvm-svn: 269997
Summary: Set default branch weight to 1:1 if one of the branch has profile missing when simplifying CFG.
Reviewers: spatel, davidxl
Subscribers: danielcdh, llvm-commits
Differential Revision: http://reviews.llvm.org/D20307
llvm-svn: 269995
In truncateToMinimalBitwidths() we were RAUW'ing an instruction then erasing it. However, that intruction could be cached in the map we're iterating over. The first check is "I->use_empty()" which in most cases would return true, as the (deleted) object was RAUW'd first so would have zero use count. However in some cases the object could have been polluted or written over and this wouldn't be the case. Also it makes valgrind, asan and traditionalists who don't like their compiler to crash sad.
No testcase as there are no externally visible symptoms apart from a crash if the stars align.
Fixes PR26509.
llvm-svn: 269908
This bug was introduced in r269728 and is the likely cause of many stage 2 ubsan bot failures.
I'll add a test in a follow-up commit assuming this fixes things properly.
llvm-svn: 269797
This is assertion is no longer necessary since we never record
constants in the live set anyway. (They are never recorded in
the initial live set, and constant bases are removed near line 2119)
Differential Revision: http://reviews.llvm.org/D20293
llvm-svn: 269764
Fix a bug introduced with rL269426 :
[InstCombine] canonicalize* LE/GE vector integer comparisons to LT/GT (PR26701, PR26819)
We were assuming that a ConstantDataVector / ConstantVector / ConstantAggregateZero operand of
an ICMP was composed of ConstantInt elements, but it might have ConstantExpr or UndefValue
elements. Handle those appropriately.
Also, refactor this function to join the scalar and vector paths and eliminate the switches.
Differential Revision: http://reviews.llvm.org/D20289
llvm-svn: 269728