Commit Graph

131 Commits

Author SHA1 Message Date
Dan Gohman
853d3fb8d2 Move PHIElimination's SplitCriticalEdge for MachineBasicBlocks out
into a utility routine, teach it how to update MachineLoopInfo, and
make use of it in MachineLICM to split critical edges on demand.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106555 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-22 17:25:57 +00:00
Stuart Hastings
3bf9125933 Add a DebugLoc parameter to TargetInstrInfo::InsertBranch(). This
addresses a longstanding deficiency noted in many FIXMEs scattered
across all the targets.

This effectively moves the problem up one level, replacing eleven
FIXMEs in the targets with eight FIXMEs in CodeGen, plus one path
through FastISel where we actually supply a DebugLoc, fixing Radar
7421831.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106243 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-17 22:43:56 +00:00
Dan Gohman
34dcc6fadc Add a DebugLoc argument to TargetInstrInfo::copyRegToReg, so that it
doesn't have to guess.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103194 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-06 20:33:48 +00:00
Evan Cheng
3d720fbc6a Move REG_SEQUENCE removal to 2addr pass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103109 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-05 18:45:40 +00:00
Evan Cheng
afff40a62d Teach PHI elimination to remove REG_SEQUENCE instructions and update references of the source operands with references of the destination with subreg indices. e.g.
%reg1029<def>, %reg1030<def> = VLD1q16 %reg1024<kill>, ...
%reg1031<def> = REG_SEQUENCE %reg1029<kill>, 5, %reg1030<kill>, 6
=>
%reg1031:5<def>, %reg1031:6<def> = VLD1q16 %reg1024<kill>, ...

PHI elimination now does more than phi elimination. It is really a de-SSA pass.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103039 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-04 20:26:52 +00:00
Evan Cheng
28428cd6f3 Rename variables for consistency.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103013 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-04 17:12:26 +00:00
Evan Cheng
48f2cb926e Avoid being influenced by dbg_value instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99465 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-25 01:01:37 +00:00
Evan Cheng
a92dced4a1 Remove PHINodeTraits and use MachineInstrExpressionTrait instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97687 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-03 23:55:49 +00:00
Jakob Stoklund Olesen
dcfe5f30b5 Keep track of phi join registers explicitly in LiveVariables.
Previously, LiveIntervalAnalysis would infer phi joins by looking for multiply
defined registers. That doesn't work if the phi join is implicitly defined in
all but one of the predecessors.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96994 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-23 22:43:58 +00:00
Jakob Stoklund Olesen
f895dbeb29 Dead code elimination
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96837 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-23 00:28:53 +00:00
Jakob Stoklund Olesen
1bf1691ed3 Dead code elimination.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96496 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-17 19:13:56 +00:00
Chris Lattner
518bb53485 move target-independent opcodes out of TargetInstrInfo
into TargetOpcodes.h.  #include the new TargetOpcodes.h
into MachineInstr.  Add new inline accessors (like isPHI())
to MachineInstr, and start using them throughout the 
codebase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95687 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-09 19:54:29 +00:00
David Greene
f788297942 Change errs() to dbgs().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92566 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 01:24:24 +00:00
Bill Wendling
3de8249078 Turn off critical edge splitting for landing pads. The introduction of a
non-landing pad basic block as the successor to a block that ends in an
unconditional jump will cause block folding to remove the added block as a
successor. Thus eventually removing it AND the landing pad entirely. Critical
edge splitting is an optimization, so we can safely turn it off when dealing
with landing pads.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91634 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-17 23:42:32 +00:00
Jakob Stoklund Olesen
74215fc29f Reuse lowered phi nodes.
Tail duplication produces lots of identical phi nodes in different basic
blocks. Teach PHIElimination to reuse the join registers when lowering a phi
node that is identical to an already lowered node. This saves virtual
registers, and more importantly it avoids creating copies the the coalescer
doesn't know how to eliminate.

Teach LiveIntervalAnalysis about the phi joins with multiple uses.

This patch significantly reduces code size produced by -pre-regalloc-taildup.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91549 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-16 18:55:53 +00:00
Chris Lattner
7896c9f436 improve portability to avoid conflicting with std::next in c++'0x.
Patch by Howard Hinnant!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90365 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-03 00:50:42 +00:00
Jakob Stoklund Olesen
8f72235a77 Move PHIElimination::isLiveOut method to LiveVariables.
We want LiveVariables clients to use methods rather than accessing the
getVarInfo data structure directly. That way it will be possible to change the
LiveVariables representation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90240 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-01 17:13:31 +00:00
Jakob Stoklund Olesen
323d8c3ed7 Be more clever about calculating live variables through new basic blocks.
When splitting a critical edge, the registers live through the edge are:

- Used in a PHI instruction, or
- Live out from the predecessor, and
- Live in to the successor.

This allows the coalescer to eliminate even more phi joins.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89530 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-21 02:05:21 +00:00
Jakob Stoklund Olesen
160069d15a Place new basic blocks immediately after their predecessor when splitting
critical edges in PHIElimination.

This has a huge impact on regalloc performance, and we recover almost all of
the 10% compile time regression that edge splitting introduced.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89381 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-19 19:42:16 +00:00
Jakob Stoklund Olesen
0257dd375d Don't require LiveVariables for PHIElimination. Enable critical edge splitting
when LiveVariables is available.

The -split-phi-edges is now gone, and so is the hack to disable it when using
the local register allocator. The PHIElimination pass no longer has
LiveVariables as a prerequisite - that is what broke the local allocator.
Instead we do critical edge splitting when possible - that is when
LiveVariables is available.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89213 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-18 18:01:35 +00:00
Jakob Stoklund Olesen
5052c1547e Fix inverted test and add testcase from failing self-host.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89167 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-18 00:02:18 +00:00
Jakob Stoklund Olesen
202344e124 Disable -split-phi-edges to unbreak the buildbots
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89142 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-17 21:23:49 +00:00
Jakob Stoklund Olesen
5493acac6f Never call UpdateTerminator() when AnalyzeBranch would fail.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89139 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-17 20:46:00 +00:00
Jakob Stoklund Olesen
95a2c8f1d0 Enable -split-phi-edges by default, except when -regalloc=local.
The local register allocator doesn't like it when LiveVariables is run.
We should also disable edge splitting under -O0, but that has to wait a bit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89125 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-17 19:15:50 +00:00
Evan Cheng
9e97f3c2e2 Revert 89021. It's miscompiling llvm-gcc driver driver at -O0.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89082 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-17 09:55:52 +00:00
Jakob Stoklund Olesen
2cbe71cdf0 Enable -split-phi-edges by default
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89021 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-17 01:07:22 +00:00
Lang Hames
b126d0530d Fix for the original bug in PR5495 - Look at uses as well as defs when determining the PHI-copy insert point.
- Patch by Andrew Canis!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@88880 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-16 02:00:09 +00:00
Jakob Stoklund Olesen
3b6ced1510 Fix bug in -split-phi-edges.
When splitting an edge after a machine basic block with fall-through, we
forgot to insert a jump instruction. Fix this by calling updateTerminator() on
the fall-through block when relevant.

Also be more precise in PHIElimination::isLiveIn.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@88728 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-14 00:38:13 +00:00
Jakob Stoklund Olesen
9aebb61daf Update MachineDominator information
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@88727 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-14 00:38:06 +00:00
Jakob Stoklund Olesen
1222287543 Fix PHIElimination optimization that uses MBB->getBasicBlock.
The BasicBlock associated with a MachineBasicBlock does not necessarily
correspond to the code in the MBB.

Don't insert a new IR BasicBlock when splitting critical edges. We are not
supposed to modify the IR during codegen, and we should be able to do just
fine with a NULL BB.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@88707 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-13 21:56:15 +00:00
Daniel Dunbar
bf4af353ed Fix -Asserts warning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@87024 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-12 20:53:43 +00:00
Jakob Stoklund Olesen
3e20475fee Fix liveness calculation when splitting critical edges during PHI elimination.
- Edges are split before any phis are eliminated, so the code is SSA.

- Create a proper IR BasicBlock for the split edges.

- LiveVariables::addNewBlock now has same syntax as
  MachineDominatorTree::addNewBlock. Algorithm calculates predecessor live-out
  set rather than successor live-in set.

This feature still causes some miscompilations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86867 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-11 19:31:31 +00:00
Jakob Stoklund Olesen
f235f13931 Teach PHIElimination to split critical edges when -split-phi-edges is enabled.
Critical edges leading to a PHI node are split when the PHI source variable is
live out from the predecessor block. This help the coalescer eliminate more
PHI joins.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86725 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-10 22:01:05 +00:00
Jakob Stoklund Olesen
e35e3c33dc Refactoring: Extract method PHIElimination::isLiveOut().
Clean up some whitespace.
No functional changes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86724 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-10 22:00:56 +00:00
Dan Gohman
845012e6d3 Use setPreservesAll and setPreservesCFG in CodeGen passes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77754 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-31 23:37:33 +00:00
Lang Hames
20354634eb For real this time: PHI Def & Kill tracking added to PHIElimination.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76865 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-23 05:44:24 +00:00
Lang Hames
287b8b0301 Added PHI Def & Kill tracking to PHIElimination pass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76849 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-23 04:34:03 +00:00
Lang Hames
fae02a2ab1 Exposed PHIElimination pass within CodeGen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76688 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-21 23:47:33 +00:00
Evan Cheng
ddb03d831b Revert 74898. It broke several tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74925 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-07 17:50:43 +00:00
Sanjiv Gupta
1dd35b4c35 if the terminator is a branch depending upon the side effects of a
previous cmp; a copy can not be inserted here if the copy insn also has
 side effects. We don't have access to the attributes of copy insn here;
 so just play safe by finding a safe locations for branch terminators.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74898 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-07 08:04:51 +00:00
Jeffrey Yasskin
493a3d015c LiveVariables::VarInfo contains an AliveBlocks BitVector, which has as many
entries as there are basic blocks in the function.  LiveVariables::getVarInfo
creates a VarInfo struct for every register in the function, leading to
quadratic space use.  This patch changes the BitVector to a SparseBitVector,
which doesn't help the worst-case memory use but does reduce the actual use in
very long functions with short-lived variables.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72426 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-26 18:27:15 +00:00
Evan Cheng
aed4a430f4 Eliminate VarInfo::UsedBlocks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72411 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-26 06:25:46 +00:00
Duncan Sands
a5fec0dba3 Reapply r67049, with the test adjusted for darwin
(which produces "call L_f$stub" rather than "call f").


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67079 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-17 09:46:22 +00:00
Bill Wendling
db14d63cea --- Reverse-merging (from foreign repository) r67049 into '.':
U    test/CodeGen/X86/2009-03-13-PHIElimBug.ll
D    test/CodeGen/X86/2009-03-16-PHIElimInLPad.ll
U    lib/CodeGen/PHIElimination.cpp

r67049 was causing this failure:

Running /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.src/test/CodeGen/X86/dg.exp ...
FAIL: /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.src/test/CodeGen/X86/2009-03-13-PHIElimBug.ll for PR3784
Failed with exit(1) at line 1
while running:  llvm-as < /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.src/test/CodeGen/X86/2009-03-13-PHIElimBug.ll |  llc -march=x86 | /usr/bin/grep -A 2 {call f} | /usr/bin/grep movl
child process exited abnormally


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67051 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-16 20:27:20 +00:00
Duncan Sands
dfec24c877 Tweak the fix for PR3784: be less sensitive about just
how invokes are set up.  The fix could be disturbed by
register copies coming after the EH_LABEL, and also didn't
behave quite right when it was the invoke result that
was used in a phi node.  Also (see new testcase) fix
another phi elimination bug while there: register copies
in the landing pad need to come after the EH_LABEL, because
that's where execution branches to when unwinding.  If they
come before the EH_LABEL then they will never be executed...
Also tweak the original testcase so it doesn't use a no-longer
existing counter.
The accumulated phi elimination changes fix two of seven Ada
testsuite failures that turned up after landing pad critical
edge splitting was turned off.  So there's probably more to come.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67049 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-16 19:58:38 +00:00
Evan Cheng
fc0b80d974 Fix PR3784: If the source of a phi comes from a bb ended with an invoke, make sure the copy is inserted before the try range (unless it's used as an input to the invoke, then insert it after the last use), not at the end of the bb.
Also re-apply r66140 which was disabled as a workaround.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66976 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-13 22:59:14 +00:00
Bill Wendling
d62e06c53b Explicitly pass in debug location information to BuildMI.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63599 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-03 02:29:34 +00:00
Duncan Sands
1465d61bdd Rename getAnalysisToUpdate to getAnalysisIfAvailable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63198 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-28 13:14:17 +00:00
Dan Gohman
ae73dc1448 Tidy up several unbeseeming casts from pointer to intptr_t.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55779 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-04 17:05:41 +00:00
Dan Gohman
8e5f2c6f65 Pool-allocation for MachineInstrs, MachineBasicBlocks, and
MachineMemOperands. The pools are owned by MachineFunctions.

This drastically reduces the number of calls to malloc/free made
during the "Emit" phase of scheduling, as well as later phases
in CodeGen. Combined with other changes, this speeds up the
"instruction selection" phase of CodeGen by 10% in some cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53212 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-07 23:14:23 +00:00