Commit Graph

19 Commits

Author SHA1 Message Date
Philip Reames 018dbf18c4 Tweak EarlyCSE to recognize series of dead stores
EarlyCSE is giving up on the current instruction immediately when it recognizes that the current instruction makes a previous store trivially dead. There's no reason to do this. Once the previous store has been deleted, it's perfectly legal to remember the value of the current store (for value forwarding) and the fact the store occurred (it could be dead too!).

Reviewed by: Hal
Differential Revision: http://reviews.llvm.org/D6301

llvm-svn: 222241
2014-11-18 17:46:32 +00:00
Hal Finkel 1e16fa302e EarlyCSE should ignore calls to @llvm.assume
EarlyCSE uses a simple generation scheme for handling memory-based
dependencies, and calls to @llvm.assume (which are marked as writing to memory
to ensure the preservation of control dependencies) disturb that scheme
unnecessarily. Skipping calls to @llvm.assume is legal, and the alternative
(adding AA calls in EarlyCSE) is likely undesirable (we have GVN for that).

Fixes PR21448.

llvm-svn: 221175
2014-11-03 20:21:32 +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 a76289aa1b Catch more CHECK that can be converted to CHECK-LABEL in Transforms for easier debugging. No functionality change.
This conversion 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/;\(.*\)\([A-Za-z0-9_]*\):\( *\)define\([^@]*\)@$FUNC\([( ]*\)\$/;\1\2-LABEL:\3define\4@$FUNC(/g" $TEMP
      done
      mv $TEMP $NAME
    fi
  done

llvm-svn: 186269
2013-07-14 01:50:49 +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
David Tweed d505b24277 Initially forgotten-to-svn-add test case for r177279.
llvm-svn: 177280
2013-03-18 12:07:24 +00:00
David Tweed a11edf0ce3 There was a switch fall-through in the parser for textual LLVM that caused
bogus comparison operands to default to eq/oeq. Fix that, fix a couple of
tests that accidentally passed and test for bogus comparison opeartors
explicitly.

llvm-svn: 171733
2013-01-07 13:32:38 +00:00
Michael Ilseman c93cffb590 New EarlyCSE tests for CSE-ing across commutativity.
llvm-svn: 165510
2012-10-09 16:58:13 +00:00
Eli Friedman c8cbd06947 Fix regression from r151466: an we can't replace uses of an instruction reachable from the entry block with uses of an instruction not reachable from the entry block. PR12231.
llvm-svn: 152595
2012-03-13 01:06:07 +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
Chris Lattner 6a144a2227 Upgrade syntax of tests using volatile instructions to use 'load volatile' instead of 'volatile load', which is archaic.
llvm-svn: 145171
2011-11-27 06:54:59 +00:00
Eli Friedman 02e737b08e Move "atomic" and "volatile" designations on instructions after the opcode
of the instruction.

Note that this change affects the existing non-atomic load and store
instructions; the parser now accepts both forms, and the change is noted
in the release notes.

llvm-svn: 137527
2011-08-12 22:50:01 +00:00
Chris Lattner bde6ec1db6 Duncan deftly points out that readnone functions aren't
invalidated by stores, so they can be handled as 'simple'
operations.

llvm-svn: 122785
2011-01-03 23:38:13 +00:00
Chris Lattner 9e5e9ed79a earlycse can do trivial with-a-block dead store
elimination as well.  This deletes 60 stores in 176.gcc
that largely come from bitfield code.

llvm-svn: 122736
2011-01-03 04:17:24 +00:00
Chris Lattner e0e32a9ef0 now that loads are in their own table, we can implement
store->load forwarding.  This allows EarlyCSE to zap 600 more
loads from 176.gcc.

llvm-svn: 122732
2011-01-03 03:46:34 +00:00
Chris Lattner 0446bb23f8 add a testcase for readonly call CSE
llvm-svn: 122730
2011-01-03 03:33:47 +00:00
Chris Lattner b9a8efc960 Teach EarlyCSE to do trivial CSE of loads and read-only calls.
On 176.gcc, this catches 13090 loads and calls, and increases the
number of simple instructions CSE'd from 29658 to 36208.

llvm-svn: 122727
2011-01-03 03:18:43 +00:00
Chris Lattner 8fac5db251 add DEBUG and -stats output to earlycse.
Teach it to CSE the rest of the non-side-effecting instructions.

llvm-svn: 122716
2011-01-02 23:19:45 +00:00
Chris Lattner 18ae5436b1 Enhance earlycse to do CSE of casts, instsimplify and die.
Add a testcase.

llvm-svn: 122715
2011-01-02 23:04:14 +00:00