195 Commits

Author SHA1 Message Date
Evan Cheng
4401f8873c Allow targets more controls on what nodes are scheduled by reg pressure, what for latency in hybrid mode.
llvm-svn: 104293
2010-05-20 23:26:43 +00:00
Evan Cheng
bdd062dae0 Add a hybrid bottom up scheduler that reduce register usage while avoiding
pipeline stall. It's useful for targets like ARM cortex-a8. NEON has a lot
of long latency instructions so a strict register pressure reduction
scheduler does not work well.
Early experiments show this speeds up some NEON loops by over 30%.

llvm-svn: 104216
2010-05-20 06:13:19 +00:00
Chris Lattner
3b9f02a2aa Three changes:
1. Introduce some enums and accessors in the InlineAsm class
   that eliminate a ton of magic numbers when handling inline
   asm SDNode.
2. Add a new MDNodeSDNode selection dag node type that holds
   a MDNode (shocking!)
3. Add a new argument to ISD::INLINEASM nodes that hold !srcloc
   metadata, propagating it to the instruction emitter, which
   drops it.

No functionality change.

llvm-svn: 100605
2010-04-07 05:20:54 +00:00
Chris Lattner
b06015aa69 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.

llvm-svn: 95687
2010-02-09 19:54:29 +00:00
Evan Cheng
3b245876c0 When the scheduler unfold a load folding instruction it move some of the predecessors to the unfolded load. It decides what gets moved to the load by checking whether the new load is using the predecessor as an operand. The check neglects the cases whether the predecessor is a flagged scheduling unit.
rdar://7604000

llvm-svn: 95339
2010-02-05 01:27:11 +00:00
Bill Wendling
8cbc25d945 Remove the '-disable-scheduling' flag and replace it with the 'source' option of
the '-pre-RA-sched' flag. It actually makes more sense to do it this way. Also,
keep track of the SDNode ordering by default. Eventually, we would like to make
this ordering a way to break a "tie" in the scheduler. However, doing that now
breaks the "CodeGen/X86/abi-isel.ll" test for 32-bit Linux.

llvm-svn: 94308
2010-01-23 10:26:57 +00:00
Bill Wendling
c075acbb54 The previous code could potentially cause a cycle. Allow ordering w.r.t. a 0 order.
llvm-svn: 92810
2010-01-06 00:23:35 +00:00
Bill Wendling
578865ff3d Only check the ordering if there is an ordering for each nodes.
llvm-svn: 92807
2010-01-06 00:09:23 +00:00
Bill Wendling
0a7056fe52 Add a semi-primitive form of scheduling via the "SDNode ordering" to the
bottom-up scheduler. We prefer the lower order number.

llvm-svn: 92806
2010-01-05 23:48:12 +00:00
David Greene
f34d7ac9f1 Change errs() to dbgs().
llvm-svn: 92576
2010-01-05 01:24:54 +00:00
Nick Lewycky
974e12b2d3 Remove includes of Support/Compiler.h that are no longer needed after the
VISIBILITY_HIDDEN removal.

llvm-svn: 85043
2009-10-25 06:57:41 +00:00
Nick Lewycky
02d5f77d26 Remove VISIBILITY_HIDDEN from class/struct found inside anonymous namespaces.
Chris claims we should never have visibility_hidden inside any .cpp file but
that's still not true even after this commit.

llvm-svn: 85042
2009-10-25 06:33:48 +00:00
Dan Gohman
918ec53c64 The ScheduleDAG framework now requires an AliasAnalysis argument, though
it isn't needed in the ScheduleDAGSDNodes schedulers.

llvm-svn: 83691
2009-10-09 23:33:48 +00:00
Reid Kleckner
cea8dab1d1 Silence comparison always false warning in -Asserts mode.
llvm-svn: 83164
2009-09-30 20:43:07 +00:00
Reid Kleckner
8ff5c19ebd Fix integer overflow in instruction scheduling. This can happen if we have
basic blocks that are so long that their size overflows a short.

Also assert that overflow does not happen in the future, as requested by Evan.

This fixes PR4401.

llvm-svn: 83159
2009-09-30 20:15:38 +00:00
Chris Lattner
317dbbcfb1 eliminate uses of cerr()
llvm-svn: 79834
2009-08-23 07:05:07 +00:00
Chris Lattner
4dc3edde9f remove a few DOUTs here and there.
llvm-svn: 79832
2009-08-23 06:35:02 +00:00
Owen Anderson
9f94459d24 Split EVT into MVT and EVT, the former representing _just_ a primitive type, while
the latter is capable of representing either a primitive or an extended type.

llvm-svn: 78713
2009-08-11 20:47:22 +00:00
Owen Anderson
53aa7a960c Rename MVT to EVT, in preparation for splitting SimpleValueType out into its own struct type.
llvm-svn: 78610
2009-08-10 22:56:29 +00:00
Torok Edwin
fbcc663cbf llvm_unreachable->llvm_unreachable(0), LLVM_UNREACHABLE->llvm_unreachable.
This adds location info for all llvm_unreachable calls (which is a macro now) in
!NDEBUG builds.
In NDEBUG builds location info and the message is off (it only prints
"UREACHABLE executed").

llvm-svn: 75640
2009-07-14 16:55:14 +00:00
Torok Edwin
56d0659726 assert(0) -> LLVM_UNREACHABLE.
Make llvm_unreachable take an optional string, thus moving the cerr<< out of
line.
LLVM_UNREACHABLE is now a simple wrapper that makes the message go away for
NDEBUG builds.

llvm-svn: 75379
2009-07-11 20:10:48 +00:00
Bill Wendling
026e5d7667 Instead of passing in an unsigned value for the optimization level, use an enum,
which better identifies what the optimization is doing. And is more flexible for
future uses.

llvm-svn: 70440
2009-04-29 23:29:43 +00:00
Bill Wendling
084669a1c9 Second attempt:
Massive check in. This changes the "-fast" flag to "-O#" in llc. If you want to
use the old behavior, the flag is -O0. This change allows for finer-grained
control over which optimizations are run at different -O levels.

Most of this work was pretty mechanical. The majority of the fixes came from
verifying that a "fast" variable wasn't used anymore. The JIT still uses a
"Fast" flag. I'll change the JIT with a follow-up patch.

llvm-svn: 70343
2009-04-29 00:15:41 +00:00
Bill Wendling
56f2987a87 r70270 isn't ready yet. Back this out. Sorry for the noise.
llvm-svn: 70275
2009-04-28 01:04:53 +00:00
Bill Wendling
d0ae15946c Massive check in. This changes the "-fast" flag to "-O#" in llc. If you want to
use the old behavior, the flag is -O0. This change allows for finer-grained
control over which optimizations are run at different -O levels.

Most of this work was pretty mechanical. The majority of the fixes came from
verifying that a "fast" variable wasn't used anymore. The JIT still uses a
"Fast" flag. I'm not 100% sure if it's necessary to change it there...

llvm-svn: 70270
2009-04-28 00:21:31 +00:00
Dan Gohman
eefba6bbe0 In the list-burr's pseudo two-addr dependency heuristics, don't
add dependencies on nodes with exactly one successor which is a
COPY_TO_REGCLASS node. In the case that the copy is coalesced
away, the dependence should be on the user of the copy, rather
than the copy itself.

llvm-svn: 69309
2009-04-16 20:59:02 +00:00
Dan Gohman
3027bb6953 Handle SUBREG_TO_REG instructions with the same heuristics
as INSERT_SUBREG instructions in the list-burr scheduler.

llvm-svn: 69308
2009-04-16 20:57:10 +00:00
Dan Gohman
f3746cbc56 Minor compile-time optimization; don't bother checking
canClobberPhysRegDefs if the successor node doesn't
clobber any physical registers.

llvm-svn: 67587
2009-03-24 00:50:07 +00:00
Dan Gohman
9a658d72db Add a pre-pass to the burr-list scheduler which makes adjustments to
help out the register pressure reduction heuristics in the case of
nodes with multiple uses. Currently this uses very conservative
heuristics, so it doesn't have a broad impact, but in cases where it
does help it can make a big difference.

llvm-svn: 67586
2009-03-24 00:49:12 +00:00
Dan Gohman
ed0e8d44ce When unfolding a load during scheduling, the new operator node has
a data dependency on the load node, so it really needs a
data-dependence edge to the load node, even if the load previously
existed.

And add a few comments.

llvm-svn: 67554
2009-03-23 20:20:43 +00:00
Dan Gohman
a366da1bf7 Fix canClobberPhysRegDefs to check all SDNodes grouped together
in an SUnit, instead of just the first one. This fix is needed
by some upcoming scheduler changes.

llvm-svn: 67531
2009-03-23 16:23:01 +00:00
Evan Cheng
2e55923fba For inline asm output operand that matches an input. Encode the input operand index in the high bits.
llvm-svn: 67387
2009-03-20 18:03:34 +00:00
Dan Gohman
a19c662a83 Fix a typo in a comment.
llvm-svn: 66843
2009-03-12 23:55:10 +00:00
Dan Gohman
15af5524a4 Fix ScheduleDAGRRList::CopyAndMoveSuccessors' handling of nodes
with multiple chain operands. This can occur when the scheduler
has added chain operands to a node that already has a chain
operand, in order to handle physical register dependencies.

This fixes an llvm-gcc bootstrap failure on x86-64 introduced
in r66058.

llvm-svn: 66240
2009-03-06 02:23:01 +00:00
Evan Cheng
b8905c4e2c Fix PR3701. 1. X86 target renamed eflags register to flags. This matches what llvm-gcc generates so codegen knows flags register is being clobbered by inline asm. 2. BURR scheduler should also check if inline asm nodes can clobber "live" physical registers. Previously it was only checking target nodes with implicit defs.
llvm-svn: 65996
2009-03-04 01:41:49 +00:00
Evan Cheng
b570499c25 Oops. Last second clean up messed things up.
llvm-svn: 64373
2009-02-12 09:52:13 +00:00
Evan Cheng
3a14efacb6 Replace one of burr scheduling heuristic with something more sensible. Now calcMaxScratches simply compute the number of true data dependencies. This actually improve a couple of tests in dejagnu suite as many tests in llvm nightly test suite.
llvm-svn: 64369
2009-02-12 08:59:45 +00:00
Dan Gohman
45889d24fe Fix a comment.
llvm-svn: 64328
2009-02-11 21:32:08 +00:00
Dan Gohman
6571ef3577 Don't use special heuristics for nodes with no data predecessors
unless they actually have data successors, and likewise for nodes
with no data successors unless they actually have data precessors.

llvm-svn: 64327
2009-02-11 21:29:39 +00:00
Dan Gohman
298a2946f1 Delete the heuristic for non-livein CopyFromReg nodes. Non-liveinness
is determined by whether the node has a Flag operand. However, if the
node does have a Flag operand, it will be glued to its register's
def, so the heuristic would end up spuriously applying to whatever
node is the def.

llvm-svn: 64319
2009-02-11 20:25:59 +00:00
Dan Gohman
dfaf646c34 When scheduling a block in parts, keep track of the overall
instruction index across each part. Instruction indices are used
to make live range queries, and live ranges can extend beyond
scheduling region boundaries.

Refactor the ScheduleDAGSDNodes class some more so that it
doesn't have to worry about this additional information.

llvm-svn: 64288
2009-02-11 04:27:20 +00:00
Dan Gohman
b95434356c Factor out more code for computing register live-range informationfor
scheduling, and generalize is so that preserves state across
scheduling regions. This fixes incorrect live-range information around
terminators and labels, which are effective region boundaries.

In place of looking for terminators to anchor inter-block dependencies,
introduce special entry and exit scheduling units for this purpose.

llvm-svn: 64254
2009-02-10 23:27:53 +00:00
Evan Cheng
ce3bbe515b Fix PR3457: Ignore control successors when looking for closest scheduled successor. A control successor doesn't read result(s) produced by the scheduling unit being evaluated.
llvm-svn: 64210
2009-02-10 08:30:11 +00:00
Dan Gohman
483377c639 Move ScheduleDAGSDNodes.h to be a private header. Front-ends
that previously included this header should include
SchedulerRegistry.h instead.

llvm-svn: 63937
2009-02-06 17:22:58 +00:00
Dan Gohman
60d6844aa8 Make a few things const, fix some comments, and simplify
some assertions.

llvm-svn: 63328
2009-01-29 19:49:27 +00:00
Dan Gohman
619ef48a52 Move a few containers out of ScheduleDAGInstrs::BuildSchedGraph
and into the ScheduleDAGInstrs class, so that they don't get
destructed and re-constructed for each block. This fixes a
compile-time hot spot in the post-pass scheduler.

To help facilitate this, tidy and do some minor reorganization
in the scheduler constructor functions.

llvm-svn: 62275
2009-01-15 19:20:50 +00:00
Dan Gohman
1407484178 The list-td and list-tdrr schedulers don't yet support physreg
scheduling dependencies. Add assertion checks to help catch
this.

It appears the Mips target defaults to list-td, and it has a
regression test that uses a physreg dependence. Such code was
liable to be miscompiled, and now evokes an assertion failure.

llvm-svn: 62177
2009-01-13 20:24:13 +00:00
Evan Cheng
b2c42c648d Fix PR3241: Currently EmitCopyFromReg emits a copy from the physical register to a virtual register unless it requires an expensive cross class copy. That means we are only treating "expensive to copy" register dependency as physical register dependency.
Also future proof the scheduler to handle "normal" physical register dependencies. The code is not exercised yet.

llvm-svn: 62074
2009-01-12 03:19:55 +00:00
Evan Cheng
0c4fe2600a Minor debug output tweak.
llvm-svn: 62005
2009-01-09 20:42:34 +00:00
Dan Gohman
261ee6be57 Remove redundant 'else's. No functionality change.
llvm-svn: 61891
2009-01-07 22:30:55 +00:00