Commit Graph

29 Commits

Author SHA1 Message Date
David Majnemer 1c297e66fb [CVP] Don't assume Constants of type i1 can be known to be true or false
CVP wants to analyze the condition operand of a select along an edge.
It succeeds in getting back a Constant but not a ConstantInt.  Instead,
it gets a ConstantExpr.  It then assumes that the Constant must be equal
to false because it isn't equal to true.

Instead, perform an additional comparison.

This fixes PR23752.

llvm-svn: 239217
2015-06-06 04:56:51 +00:00
Bjorn Steinbrink 2833966a3c CVP: Improve handling of Selects used as incoming PHI values
Summary:
If the branch that leads to the PHI node and the Select instruction
depend on correlated conditions, we might be able to directly use the
corresponding value from the Select instruction as the incoming value
for the PHI node, allowing later removal of the select instruction.

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9051

llvm-svn: 237201
2015-05-12 22:31:47 +00:00
David Blaikie a79ac14fa6 [opaque pointer type] Add textual IR support for explicit type parameter to load instruction
Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)

import fileinput
import sys
import re

pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")

for line in sys.stdin:
  sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7649

llvm-svn: 230794
2015-02-27 21:17:42 +00:00
Hans Wennborg 45172aceb3 LazyValueInfo: Actually re-visit partially solved block-values in solveBlockValue()
If solveBlockValue() needs results from predecessors that are not already
computed, it returns false with the intention of resuming when the dependencies
have been resolved. However, the computation would never be resumed since an
'overdefined' result had been placed in the cache, preventing any further
computation.

The point of placing the 'overdefined' result in the cache seems to have been
to break cycles, but we can check for that when inserting work items in the
BlockValue stack instead. This makes the "stop and resume" mechanism of
solveBlockValue() work as intended, unlocking more analysis.

Using this patch shaves 120 KB off a 64-bit Chromium build on Linux.

I benchmarked compiling bzip2.c at -O2 but couldn't measure any difference in
compile time.

Tests by Jiangning Liu from r215343 / PR21238, Pete Cooper, and me.

Differential Revision: http://reviews.llvm.org/D6397

llvm-svn: 222768
2014-11-25 17:23:05 +00:00
Daniel Dunbar 9efbedfd35 [tests] Cleanup initialization of test suffixes.
- Instead of setting the suffixes in a bunch of places, just set one master
   list in the top-level config. We now only modify the suffix list in a few
   suites that have one particular unique suffix (.ml, .mc, .yaml, .td, .py).

 - Aside from removing the need for a bunch of lit.local.cfg files, this enables
   4 tests that were inadvertently being skipped (one in
   Transforms/BranchFolding, a .s file each in DebugInfo/AArch64 and
   CodeGen/PowerPC, and one in CodeGen/SI which is now failing and has been
   XFAILED).

 - This commit also fixes a bunch of config files to use config.root instead of
   older copy-pasted code.

llvm-svn: 188513
2013-08-16 00:37:11 +00:00
Stephen Lin c1c7a1309c Update Transforms tests to use CHECK-LABEL for easier debugging. No functionality change.
This update was done with the following bash script:

  find test/Transforms -name "*.ll" | \
  while read NAME; do
    echo "$NAME"
    if ! grep -q "^; *RUN: *llc" $NAME; then
      TEMP=`mktemp -t temp`
      cp $NAME $TEMP
      sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \
      while read FUNC; do
        sed -i '' "s/;\(.*\)\([A-Za-z0-9_]*\):\( *\)@$FUNC\([( ]*\)\$/;\1\2-LABEL:\3@$FUNC(/g" $TEMP
      done
      mv $TEMP $NAME
    fi
  done

llvm-svn: 186268
2013-07-14 01:42:54 +00:00
Stephen Lin 6dd347b39f Add newlines at end of test files, no functionality change
llvm-svn: 186263
2013-07-13 22:00:58 +00:00
Benjamin Kramer ee40b9a2d4 CVP: If we have a PHI with an incoming select, try to skip the select.
This is a common pattern with dyn_cast and similar constructs, when the
PHI no longer depends on the select it can often be turned into a simpler
construct or even get hoisted out of the loop.

PR15340.

llvm-svn: 175995
2013-02-24 15:34:43 +00:00
Benjamin Kramer b867fea5e6 Fix invalid IR in test, missing incoming value for PHI node.
llvm-svn: 175994
2013-02-24 15:34:29 +00:00
Benjamin Kramer 255dea4b90 CorrelatedPropagation: BasicBlock::removePredecessor can simplify PHI nodes. If the it's the condition of a SwitchInst, reload it.
Fixes PR13972.

llvm-svn: 164818
2012-09-28 10:42:50 +00:00
Nuno Lopes 8650fb8e0e make LazyValueInfo analyze the default case of switch statements (we know that in the default branch the value cannot be any of the switch cases)
llvm-svn: 159353
2012-06-28 16:13:37 +00:00
Nuno Lopes e6e049020b make LVI::getEdgeValue() always intersect the constraints of the edge with the range of the block. Previously it was only performing the intersection for a few cases, thus losing precision
llvm-svn: 159320
2012-06-28 01:16:18 +00:00
Nuno Lopes ac59380dfd allow LazyValueInfo::getEdgeValue() to reason about multiple edges from the same switch instruction by doing union of ranges (which may still be conservative, but it's more aggressive than before)
llvm-svn: 157071
2012-05-18 21:02:10 +00:00
Nuno Lopes b63d6cdf79 add test case for bugfix in r157032
llvm-svn: 157058
2012-05-18 17:44:58 +00:00
Duncan Sands cca89124a2 Eliminate switch cases that can never match, for example removes all
negative switch cases if the branch condition is known to be positive.
Inspired by a recent improvement to GCC's VRP.

llvm-svn: 152405
2012-03-09 13:45:18 +00:00
Benjamin Kramer d9d80b1dde LVI: Recognize the form instcombine canonicalizes range checks into when forming constant ranges.
This could probably be made a lot smarter, but this is a common case and doesn't require LVI to scan a lot
of code. With this change CVP can optimize away the "shift == 0" case in Hashing.h that only gets hit when
"shift" is in a range not containing 0.

llvm-svn: 151919
2012-03-02 15:34:43 +00:00
Eli Bendersky 924f9a671d Replace all instances of dg.exp file with lit.local.cfg, since all tests are run with LIT now and now Dejagnu. dg.exp is no longer needed.
Patch reviewed by Daniel Dunbar. It will be followed by additional cleanup patches.

llvm-svn: 150664
2012-02-16 06:28:33 +00:00
Nick Lewycky 872a453ada Test for lazy value info's ability to prove the absense of NULLs in pointers.
llvm-svn: 123601
2011-01-16 21:57:20 +00:00
Owen Anderson 35609d97ae Fix PR8790, another instance where unreachable code can cause instruction simplification to fail,
this case involve a select that simplifies to itself.

llvm-svn: 121817
2010-12-15 00:55:35 +00:00
Owen Anderson 8e7b73743d Update testcase since we're no longer doing the constant forwarding inline with correlated value propagation.
llvm-svn: 117712
2010-10-29 21:18:23 +00:00
Owen Anderson 20154b3ed4 Add missing RUN line to this test.
llvm-svn: 114106
2010-09-16 18:46:23 +00:00
Owen Anderson 140296f5c0 It is possible, under specific circumstances involving ptrtoint ConstantExpr's, for LVI to end up trying to merge
a Constant into a ConstantRange.  Handle this conservatively for now, rather than asserting.  The testcase is
more complex that I would like, but the manifestation of the problem is sensitive to iteration orders and the state of the
LVI cache, and I have not been able to reproduce it with manually constructed or simplified cases.

Fixes PR8162.

llvm-svn: 114103
2010-09-16 18:28:33 +00:00
Owen Anderson 94532cb297 Fix PR8161, in which an unreachable loop causes recursive instruction simplification to try
to replace an instruction with itself.  Add a predicate to the simplifier to prevent this case.

llvm-svn: 114097
2010-09-16 17:42:36 +00:00
Owen Anderson c91c1a205a Propagate non-local comparisons. Fixes PR1757.
llvm-svn: 113025
2010-09-03 22:47:08 +00:00
Owen Anderson c725462245 Add support for simplifying a load from a computed value to a load from a global when it
is provable that they're equivalent.  This fixes PR4855.

llvm-svn: 112994
2010-09-03 19:08:37 +00:00
Owen Anderson 50d8c8888c Add PR number to test.
llvm-svn: 112971
2010-09-03 16:58:25 +00:00
Owen Anderson 67dee4dcac Fix typo. I accidentally edited the wrong file before my last commit.
llvm-svn: 112851
2010-09-02 19:52:06 +00:00
Owen Anderson a8c896b704 Fix a bug in LazyValueInfo that CorrelatedValuePropagation exposed: In the LVI lattice, undef and the full set ConstantRange should not
be treated as equivalent.

llvm-svn: 112843
2010-09-02 18:23:58 +00:00
Owen Anderson 064b139c8d Rename test directory to reflect new pass name.
llvm-svn: 112592
2010-08-31 07:50:31 +00:00