Commit Graph

226 Commits

Author SHA1 Message Date
Gabor Greif abfdf928d8 disallow direct access to SDValue::ResNo, provide a getter instead
llvm-svn: 55394
2008-08-26 22:36:50 +00:00
Dan Gohman 2ce6f2ad5e Rename SDOperand to SDValue.
llvm-svn: 54128
2008-07-27 21:46:04 +00:00
Dan Gohman 91e5dcb680 Tidy SDNode::use_iterator, and complete the transition to have it
parallel its analogue, Value::value_use_iterator. The operator* method
now returns the user, rather than the use.

llvm-svn: 54127
2008-07-27 20:43:25 +00:00
Dan Gohman 1705968102 Add a new function, ReplaceAllUsesOfValuesWith, which handles bulk
replacement of multiple values. This is slightly more efficient
than doing multiple ReplaceAllUsesOfValueWith calls, and theoretically
could be optimized even further. However, an important property of this
new function is that it handles the case where the source value set and
destination value set overlap. This makes it feasible for isel to use
SelectNodeTo in many very common cases, which is advantageous because
SelectNodeTo avoids a temporary node and it doesn't require CSEMap
updates for users of values that don't change position.

Revamp MorphNodeTo, which is what does all the work of SelectNodeTo, to
handle operand lists more efficiently, and to correctly handle a number
of corner cases to which its new wider use exposes it.

This commit also includes a change to the encoding of post-isel opcodes
in SDNodes; now instead of being sandwiched between the target-independent
pre-isel opcodes and the target-dependent pre-isel opcodes, post-isel
opcodes are now represented as negative values. This makes it possible
to test if an opcode is pre-isel or post-isel without having to know
the size of the current target's post-isel instruction set.

These changes speed up llc overall by 3% and reduce memory usage by 10%
on the InstructionCombining.cpp testcase with -fast and -regalloc=local.

llvm-svn: 53728
2008-07-17 19:10:17 +00:00
Dan Gohman adec96f438 Reapply 53476 and 53480, with a fix so that it properly updates
the BB member to the current basic block after emitting
instructions.

llvm-svn: 53567
2008-07-14 18:19:29 +00:00
Evan Cheng ef8412c822 Back out 53476 and 53480 for now. Somehow they cause llc to miscompile 179.art.
llvm-svn: 53502
2008-07-12 01:38:51 +00:00
Dan Gohman ed087a62dc Fix an obsolete top-level comment.
llvm-svn: 53481
2008-07-11 22:39:58 +00:00
Dan Gohman f4cd404e6f Factor out debugging code into the common base class.
llvm-svn: 53480
2008-07-11 22:36:22 +00:00
Dan Gohman 3b46030375 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.

llvm-svn: 53212
2008-07-07 23:14:23 +00:00
Dan Gohman 38740a98b2 Make DenseMap's insert return a pair, to more closely resemble std::map.
llvm-svn: 53177
2008-07-07 17:46:23 +00:00
Dan Gohman 22e9707480 Replace a few uses of SelectionDAG::getTargetNode with
SelectionDAG::SelectNodeTo in the instruction selector. This
updates existing nodes in place instead of creating new ones.

Go back to selecting ISD::DBG_LABEL nodes into
TargetInstrInfo::DBG_LABEL nodes instead of leaving them
unselected, now that SelectNodeTo allows us to update them
in place.

llvm-svn: 53057
2008-07-02 23:23:19 +00:00
Evan Cheng 7e4abde27c - Use a faster priority comparison function if -fast.
- Code clean up.

llvm-svn: 53010
2008-07-02 09:23:51 +00:00
Dan Gohman fb19f9402b Split ISD::LABEL into ISD::DBG_LABEL and ISD::EH_LABEL, eliminating
the need for a flavor operand, and add a new SDNode subclass,
LabelSDNode, for use with them to eliminate the need for a label id
operand.

Change instruction selection to let these label nodes through
unmodified instead of creating copies of them. Teach the MachineInstr
emitter how to emit a MachineInstr directly from an ISD label node.

This avoids the need for allocating SDNodes for the label id and
flavor value, as well as SDNodes for each of the post-isel label,
label id, and label flavor.

llvm-svn: 52943
2008-07-01 00:05:16 +00:00
Dan Gohman 14b911d929 Remove a redundant return.
llvm-svn: 52585
2008-06-21 19:34:57 +00:00
Dan Gohman 46520a25a4 Remove ScheduleDAG's SUnitMap altogether. Instead, use SDNode's NodeId
field, which is otherwise unused after instruction selection, as an index
into the SUnit array.

llvm-svn: 52583
2008-06-21 19:18:17 +00:00
Dan Gohman a4db3352f9 Add a priority queue class, which is a wrapper around std::priority_queue
and provides fairly efficient removal of arbitrary elements. Switch
ScheduleDAGRRList from std::set to this new priority queue.

llvm-svn: 52582
2008-06-21 18:35:25 +00:00
Dan Gohman e6e1348275 Change ScheduleDAG's SUnitMap from DenseMap<SDNode*, vector<SUnit*> >
to DenseMap<SDNode*, SUnit*>, and adjust the way cloned SUnit nodes are
handled so that only the original node needs to be in the map.
This speeds up llc on 447.dealII.llvm.bc by about 2%.

llvm-svn: 52576
2008-06-21 15:52:51 +00:00
Dan Gohman 3792c470d5 Clean up some uses of std::distance, now that we have allnodes_size.
llvm-svn: 52545
2008-06-20 17:15:19 +00:00
Duncan Sands 13237ac3b9 Wrap MVT::ValueType in a struct to get type safety
and better control the abstraction.  Rename the type
to MVT.  To update out-of-tree patches, the main
thing to do is to rename MVT::ValueType to MVT, and
rewrite expressions like MVT::getSizeInBits(VT) in
the form VT.getSizeInBits().  Use VT.getSimpleVT()
to extract a MVT::SimpleValueType for use in switch
statements (you will get an assert failure if VT is
an extended value type - these shouldn't exist after
type legalization).
This results in a small speedup of codegen and no
new testsuite failures (x86-64 linux).

llvm-svn: 52044
2008-06-06 12:08:01 +00:00
Evan Cheng 4ea9d49590 Use a better idiom to silence compiler warnings.
llvm-svn: 51131
2008-05-14 21:08:07 +00:00
Evan Cheng a5b0a8d7fe Really silence compiler warnings.
llvm-svn: 51123
2008-05-14 20:26:35 +00:00
Evan Cheng 763ec13862 Silence some compiler warnings.
llvm-svn: 51115
2008-05-14 20:07:51 +00:00
Chris Lattner 3b18762f40 Switch to using Simplified ConstantFP::get API.
llvm-svn: 49977
2008-04-20 00:41:09 +00:00
Roman Levenstein a3ee1a38a3 Ongoing work on improving the instruction selection infrastructure:
Rename SDOperandImpl back to SDOperand.
Introduce the SDUse class that represents a use of the SDNode referred by
an SDOperand. Now it is more similar to Use/Value classes.

Patch is approved by Dan Gohman.

llvm-svn: 49795
2008-04-16 16:15:27 +00:00
Dan Gohman 4370f26750 Treat EntryToken nodes as "passive" so that they aren't added to the
ScheduleDAG; they don't correspond to any actual instructions so they
don't need to be scheduled.

This fixes a bug where the EntryToken was being scheduled multiple
times in some cases, though it ended up not causing any trouble because 
EntryToken doesn't expand into anything. With this fixed the schedulers
reliably schedule the expected number of units, so we can check this
with an assertion.

This requires a tweak to test/CodeGen/X86/loop-hoist.ll because it
ends up getting scheduled differently in a trivial way, though it was
enough to fool the prcontext+grep that the test does.

llvm-svn: 49701
2008-04-15 01:22:18 +00:00
Dan Gohman 3bc3ddd638 Rename MemOperand to MachineMemOperand. This was suggested by
review feedback from Chris quite a while ago. No functionality
change.

llvm-svn: 49348
2008-04-07 19:35:22 +00:00
Roman Levenstein 51f532f92d Re-commit of the r48822, where the infinite looping problem discovered
by Dan Gohman is fixed.

llvm-svn: 49330
2008-04-07 10:06:32 +00:00
Evan Cheng 916802a78e Start of a series of patches related to implicit_def.
There is no point in creating a long live range defined by an implicit_def. Scheduler now duplicates implicit_def instruction for each of its uses. Therefore, if an implicit_def node has multiple uses, it will become a number of very short live ranges, rather than a long one. This will make coalescer's job easier.

llvm-svn: 49164
2008-04-03 16:36:07 +00:00
Evan Cheng 025cea1126 Backing out 48222 temporarily.
llvm-svn: 49124
2008-04-03 03:13:16 +00:00
Roman Levenstein 358e04a185 Use a linked data structure for the uses lists of an SDNode, just like
LLVM Value/Use does and MachineRegisterInfo/MachineOperand does.
This allows constant time for all uses list maintenance operations.

The idea was suggested by Chris. Reviewed by Evan and Dan.
Patch is tested and approved by Dan.

On normal use-cases compilation speed is not affected. On very big basic
blocks there are compilation speedups in the range of 15-20% or even better. 

llvm-svn: 48822
2008-03-26 12:39:26 +00:00
Dan Gohman bdc24adaaf A quick nm audit turned up several fixed tables and objects that were
marked read-write. Use const so that they can be allocated in a
read-only segment.

llvm-svn: 48800
2008-03-25 21:45:14 +00:00
Christopher Lamb d3d0ad3f58 Make insert_subreg a two-address instruction, vastly simplifying LowerSubregs pass. Add a new TII, subreg_to_reg, which is like insert_subreg except that it takes an immediate implicit value to insert into rather than a register.
llvm-svn: 48412
2008-03-16 03:12:01 +00:00
Evan Cheng 0e7b00d79f Replace all target specific implicit def instructions with a target independent one: TargetInstrInfo::IMPLICIT_DEF.
llvm-svn: 48380
2008-03-15 00:03:38 +00:00
Evan Cheng db443ca377 Livein copy scheduling fixes: do not coalesce physical register copies, correctly determine the safe location to insert the copies.
llvm-svn: 48348
2008-03-14 00:14:55 +00:00
Evan Cheng 65e9d5f1a8 Experimental scheduler change to schedule / coalesce the copies added for function livein's. Take 2008-03-10-RegAllocInfLoop.ll, the schedule looks like this after these copies are inserted:
entry: 0x12049d0, LLVM BB @0x1201fd0, ID#0:
Live Ins: %EAX %EDX %ECX
        %reg1031<def> = MOVPC32r 0
        %reg1032<def> = ADD32ri %reg1031, <es:_GLOBAL_OFFSET_TABLE_>, %EFLAGS<imp-def>
        %reg1028<def> = MOV32rr %EAX
        %reg1029<def> = MOV32rr %EDX
        %reg1030<def> = MOV32rr %ECX
        %reg1027<def> = MOV8rm %reg0, 1, %reg0, 0, Mem:LD(1,1) [0x1201910 + 0]
        %reg1025<def> = MOV32rr %reg1029
        %reg1026<def> = MOV32rr %reg1030
        %reg1024<def> = MOV32rr %reg1028

The copies unnecessarily increase register pressure and it will end up requiring a physical register to be spilled.

With -schedule-livein-copies:
entry: 0x12049d0, LLVM BB @0x1201fa0, ID#0:
Live Ins: %EAX %EDX %ECX
        %reg1031<def> = MOVPC32r 0
        %reg1032<def> = ADD32ri %reg1031, <es:_GLOBAL_OFFSET_TABLE_>, %EFLAGS<imp-def>
        %reg1024<def> = MOV32rr %EAX
        %reg1025<def> = MOV32rr %EDX
        %reg1026<def> = MOV32rr %ECX
        %reg1027<def> = MOV8rm %reg0, 1, %reg0, 0, Mem:LD(1,1) [0x12018e0 + 0]

Much better!

llvm-svn: 48307
2008-03-12 22:19:41 +00:00
Christopher Lamb aa7c2105de Recommitting parts of r48130. These do not appear to cause the observed failures.
llvm-svn: 48223
2008-03-11 10:09:17 +00:00
Evan Cheng e88a625ecd When the register allocator runs out of registers, spill a physical register around the def's and use's of the interval being allocated to make it possible for the interval to target a register and spill it right away and restore a register for uses. This likely generates terrible code but is before than aborting.
llvm-svn: 48218
2008-03-11 07:19:34 +00:00
Chris Lattner 3e0ec65678 variadic instructions don't have operand info for variadic arguments.
llvm-svn: 48208
2008-03-11 03:14:42 +00:00
Chris Lattner d3090bcfc8 If a register operand comes from the variadic part of a node, don't
verify the register constraint matches what the instruction expects.

llvm-svn: 48205
2008-03-11 00:59:28 +00:00
Dan Gohman 2a3aeb1f72 Correctly clone FlaggedNodes.
llvm-svn: 48196
2008-03-10 23:48:14 +00:00
Evan Cheng d4e1d9eeb2 Revert 48125, 48126, and 48130 for now to unbreak some x86-64 tests.
llvm-svn: 48167
2008-03-10 19:31:26 +00:00
Christopher Lamb 4ba3f0430b Allow insert_subreg into implicit, target-specific values.
Change insert/extract subreg instructions to be able to be used in TableGen patterns.
Use the above features to reimplement an x86-64 pseudo instruction as a pattern.

llvm-svn: 48130
2008-03-10 06:12:08 +00:00
Chris Lattner 86829f0ff7 teach X86InstrInfo::copyRegToReg how to copy into ST(0) from
an RFP register class.

Teach ScheduleDAG how to handle CopyToReg with different src/dst 
reg classes.

This allows us to compile trivial inline asms that expect stuff
on the top of x87-fp stack.

llvm-svn: 48107
2008-03-09 09:15:31 +00:00
Chris Lattner 9e07537e8c Add ScheduleDAG support for copytoreg where the src/dst register are
in different register classes, e.g. copy of ST(0) to RFP*.  This gets
some really trivial inline asm working that plops things on the top of
stack (PR879)

llvm-svn: 48105
2008-03-09 08:49:15 +00:00
Chris Lattner 381bbdb924 fix 80 col violation
llvm-svn: 48100
2008-03-09 07:51:01 +00:00
Roman Levenstein c62c2bb4d0 Some improvements related to the computation of heights, depths of SUnits.
The basic idea is that all these algorithms are computing the longest paths from the root node or to the exit node. Therefore the existing implementation that uses and iterative and potentially
exponential algorithm was changed to a well-known graph algorithm based on dynamic programming. It has a linear run-time.

llvm-svn: 47884
2008-03-04 11:19:43 +00:00
Evan Cheng 567d2e5b57 Rename isOperand() to isOperandOf() (and other similar methods). It always confuses me.
llvm-svn: 47872
2008-03-04 00:41:45 +00:00
Evan Cheng a465bfb87c Keep track how many commutes are performed by the scheduler.
llvm-svn: 47710
2008-02-28 07:40:24 +00:00
Dan Gohman 27ae573900 Rename CountMemOperands to ComputeMemOperandsEnd to reflect what
it actually does. Simplify CountOperands a little by reusing
ComputeMemOperandsEnd. And reword some comments for both.

llvm-svn: 47198
2008-02-16 00:36:48 +00:00
Nate Begeman 53e1b3f9d5 Change how FP immediates are handled.
1) ConstantFP is now expand by default
2) ConstantFP is not turned into TargetConstantFP during Legalize
   if it is legal.

This allows ConstantFP to be handled like Constant, allowing for 
targets that can encode FP immediates as MachineOperands.

As a bonus, fix up Itanium FP constants, which now correctly match,
and match more constants!  Hooray.

llvm-svn: 47121
2008-02-14 08:57:00 +00:00