Commit Graph

207 Commits

Author SHA1 Message Date
Chris Lattner b0d06b4381 Move a bunch more accessors from TargetInstrInfo to TargetInstrDescriptor
llvm-svn: 45680
2008-01-07 03:13:06 +00:00
Chris Lattner d34c47653e remove some uses of MachineOpCode, move getSchedClass
into TargetInstrDescriptor from TargetInstrInfo.

llvm-svn: 45678
2008-01-07 02:46:03 +00:00
Chris Lattner e55e115616 Add predicates methods to TargetOperandInfo, and switch all clients
over to using them, instead of diddling Flags directly.  Change the
various flags from const variables to enums.

llvm-svn: 45677
2008-01-07 02:39:19 +00:00
Chris Lattner a98c679de0 Rename MachineInstr::getInstrDescriptor -> getDesc(), which reflects
that it is cheap and efficient to get.

Move a variety of predicates from TargetInstrInfo into 
TargetInstrDescriptor, which makes it much easier to query a predicate
when you don't have TII around.  Now you can use MI->getDesc()->isBranch()
instead of going through TII, and this is much more efficient anyway. Not
all of the predicates have been moved over yet.

Update old code that used MI->getInstrDescriptor()->Flags to use the
new predicates in many places.

llvm-svn: 45674
2008-01-07 01:56:04 +00:00
Owen Anderson 7a73ae9a86 Move copyRegToReg from MRegisterInfo to TargetInstrInfo. This is part of the
Machine-level API cleanup instigated by Chris.

llvm-svn: 45470
2007-12-31 06:32:00 +00:00
Chris Lattner 21ec2b4769 update a couple of references to SSARegMap.
llvm-svn: 45468
2007-12-31 04:16:08 +00:00
Chris Lattner a10fff51d9 Rename SSARegMap -> MachineRegisterInfo in keeping with the idea
that "machine" classes are used to represent the current state of
the code being compiled.  Given this expanded name, we can start 
moving other stuff into it.  For now, move the UsedPhysRegs and
LiveIn/LoveOuts vectors from MachineFunction into it.

Update all the clients to match.

This also reduces some needless #includes, such as MachineModuleInfo
from MachineFunction.

llvm-svn: 45467
2007-12-31 04:13:23 +00:00
Chris Lattner bbbae8e1ce use simplified operand addition methods.
llvm-svn: 45435
2007-12-30 00:51:11 +00:00
Chris Lattner e35dfb827f Start using the simplified methods for adding operands.
llvm-svn: 45432
2007-12-30 00:41:17 +00:00
Chris Lattner f3ebc3f3d2 Remove attribution from file headers, per discussion on llvmdev.
llvm-svn: 45418
2007-12-29 20:36:04 +00:00
Evan Cheng 0fcf56f8f5 Bug fix. Must also match ResNo when matching an operand with a user.
llvm-svn: 45028
2007-12-14 08:25:15 +00:00
Dale Johannesen 4646aa3e33 Make labels work in asm blocks; allow labels as
parameters.  Rename ValueRefList to ParamList
in AsmParser, since its only use is for parameters.

llvm-svn: 43734
2007-11-05 21:20:28 +00:00
Duncan Sands 44b8721de8 Executive summary: getTypeSize -> getTypeStoreSize / getABITypeSize.
The meaning of getTypeSize was not clear - clarifying it is important
now that we have x86 long double and arbitrary precision integers.
The issue with long double is that it requires 80 bits, and this is
not a multiple of its alignment.  This gives a primitive type for
which getTypeSize differed from getABITypeSize.  For arbitrary precision
integers it is even worse: there is the minimum number of bits needed to
hold the type (eg: 36 for an i36), the maximum number of bits that will
be overwriten when storing the type (40 bits for i36) and the ABI size
(i.e. the storage size rounded up to a multiple of the alignment; 64 bits
for i36).

This patch removes getTypeSize (not really - it is still there but
deprecated to allow for a gradual transition).  Instead there is:

(1) getTypeSizeInBits - a number of bits that suffices to hold all
values of the type.  For a primitive type, this is the minimum number
of bits.  For an i36 this is 36 bits.  For x86 long double it is 80.
This corresponds to gcc's TYPE_PRECISION.

(2) getTypeStoreSizeInBits - the maximum number of bits that is
written when storing the type (or read when reading it).  For an
i36 this is 40 bits, for an x86 long double it is 80 bits.  This
is the size alias analysis is interested in (getTypeStoreSize
returns the number of bytes).  There doesn't seem to be anything
corresponding to this in gcc.

(3) getABITypeSizeInBits - this is getTypeStoreSizeInBits rounded
up to a multiple of the alignment.  For an i36 this is 64, for an
x86 long double this is 96 or 128 depending on the OS.  This is the
spacing between consecutive elements when you form an array out of
this type (getABITypeSize returns the number of bytes).  This is
TYPE_SIZE in gcc.

Since successive elements in a SequentialType (arrays, pointers
and vectors) need to be aligned, the spacing between them will be
given by getABITypeSize.  This means that the size of an array
is the length times the getABITypeSize.  It also means that GEP
computations need to use getABITypeSize when computing offsets.
Furthermore, if an alloca allocates several elements at once then
these too need to be aligned, so the size of the alloca has to be
the number of elements multiplied by getABITypeSize.  Logically
speaking this doesn't have to be the case when allocating just
one element, but it is simpler to also use getABITypeSize in this
case.  So alloca's and mallocs should use getABITypeSize.  Finally,
since gcc's only notion of size is that given by getABITypeSize, if
you want to output assembler etc the same as gcc then getABITypeSize
is the size you want.

Since a store will overwrite no more than getTypeStoreSize bytes,
and a read will read no more than that many bytes, this is the
notion of size appropriate for alias analysis calculations.

In this patch I have corrected all type size uses except some of
those in ScalarReplAggregates, lib/Codegen, lib/Target (the hard
cases).  I will get around to auditing these too at some point,
but I could do with some help.

Finally, I made one change which I think wise but others might
consider pointless and suboptimal: in an unpacked struct the
amount of space allocated for a field is now given by the ABI
size rather than getTypeStoreSize.  I did this because every
other place that reserves memory for a type (eg: alloca) now
uses getABITypeSize, and I didn't want to make an exception
for unpacked structs, i.e. I did it to make things more uniform.
This only effects structs containing long doubles and arbitrary
precision integers.  If someone wants to pack these types more
tightly they can always use a packed struct.

llvm-svn: 43620
2007-11-01 20:53:16 +00:00
Evan Cheng aa2d6ef81d EXTRACT_SUBREG coalescing support. The coalescer now treats EXTRACT_SUBREG like
(almost) a register copy. However, it always coalesced to the register of the
RHS (the super-register). All uses of the result of a EXTRACT_SUBREG are sub-
register uses which adds subtle complications to load folding, spiller rewrite,
etc.

llvm-svn: 42899
2007-10-12 08:50:34 +00:00
Evan Cheng 79e9713b11 If a node that defines a physical register that is expensive to copy. The
scheduler will try a number of tricks in order to avoid generating the
copies. This may not be possible in case the node produces a chain value
that prevent movement. Try unfolding the load from the node before to allow
it to be moved / cloned.

llvm-svn: 42625
2007-10-05 01:39:18 +00:00
Dan Gohman c731c97fac Use empty() member functions when that's what's being tested for instead
of comparing begin() and end().

llvm-svn: 42585
2007-10-03 19:26:29 +00:00
Evan Cheng a5e595d23a If two instructions are both two-address code, favors (schedule closer to
terminator) the one that has a CopyToReg use. This fixes
2006-05-11-InstrSched.ll with -new-cc-modeling-scheme.

llvm-svn: 42453
2007-09-28 22:32:30 +00:00
Evan Cheng 038dcc5136 Trim some unneeded fields.
llvm-svn: 42442
2007-09-28 19:24:24 +00:00
Evan Cheng 8e136a9dc4 - Move getPhysicalRegisterRegClass() from ScheduleDAG to MRegisterInfo.
- Added ability to emit cross class register copies to the BBRU scheduler.
- More aggressive backtracking.

llvm-svn: 42375
2007-09-26 21:36:17 +00:00
Evan Cheng c1e4e3743b Allow copyRegToReg to emit cross register classes copies.
Tested with "make check"!

llvm-svn: 42346
2007-09-26 06:25:56 +00:00
Evan Cheng 5924bf7d3b Added major new capabilities to scheduler (only BURR for now) to support physical register dependency. The BURR scheduler can now backtrace and duplicate instructions in order to avoid "expensive / impossible to copy" values (e.g. status flag EFLAGS for x86) from being clobbered.
llvm-svn: 42284
2007-09-25 01:54:36 +00:00
Evan Cheng 0effc3a6b8 Use struct SDep instead of std::pair for SUnit pred and succ lists. First step
in tracking physical register output dependencies.

llvm-svn: 42125
2007-09-19 01:38:40 +00:00
Evan Cheng 57ff158255 Remove dead code.
llvm-svn: 41899
2007-09-12 23:45:46 +00:00
Chris Lattner dbfc4e4b07 Teach the dag scheduler to handle inline asm nodes with multi-value immediate operands.
llvm-svn: 41386
2007-08-25 00:53:07 +00:00
Evan Cheng 358c3d1dac Do not emit copies for physical register output if it's not used.
llvm-svn: 40722
2007-08-02 05:29:38 +00:00
Evan Cheng c5549fc3a0 Instead of adding copyfromreg's to handle physical definitions. Now isel can
simply specify them as results and let scheduledag handle them. That
is, instead of
SDOperand Flag = DAG.getTargetNode(Opc, MVT::i32, MVT::Flag, ...)
SDOperand Result = DAG.getCopyFromReg(Chain, X86::EAX, MVT::i32, Flag)

Just write:
SDOperand Result = DAG.getTargetNode(Opc, MVT::i32, MVT::i32, ...)

And let scheduledag emit the move from X86::EAX to a virtual register.

llvm-svn: 40710
2007-08-02 00:28:15 +00:00
Christopher Lamb 18603b03e1 Teach DAG scheduling how to properly emit subreg insert/extract machine instructions. PR1350
llvm-svn: 40520
2007-07-26 08:12:07 +00:00
Dale Johannesen 2182f06f2d Skeleton of post-RA scheduler; doesn't do anything yet.
Change name of -sched option and DEBUG_TYPE to
pre-RA-sched; adjust testcases.

llvm-svn: 39816
2007-07-13 17:13:54 +00:00
Evan Cheng 5e9084207f If the operand is marked M_OPTIONAL_DEF_OPERAND, then it's a def.
llvm-svn: 38496
2007-07-10 17:52:20 +00:00
Evan Cheng ff6f279adf When a node value is only used by a CopyToReg, use the user's dest. This should not be restricted to nodes that produce only a single value.
llvm-svn: 38485
2007-07-10 07:08:32 +00:00
Evan Cheng 642be16bbf Change CalculateHeights and CalculateDepths to be non-recursive.
llvm-svn: 37934
2007-07-06 01:37:28 +00:00
Dan Gohman a7644dd9b9 Pass a SelectionDAG into SDNode::dump everywhere it's used, in prepration
for needing the DAG node to print pre-legalize extended value types, and
to get better debug messages with target-specific nodes.

llvm-svn: 37656
2007-06-19 14:13:56 +00:00
Jeff Cohen 1baf5c84ab Fix some VC++ warnings.
llvm-svn: 35224
2007-03-20 20:43:18 +00:00
Lauro Ramos Venancio 971aa18867 Code clean up.
llvm-svn: 35220
2007-03-20 20:09:03 +00:00
Lauro Ramos Venancio 25878b45f5 CopyToReg source operand can be a physical register.
llvm-svn: 35213
2007-03-20 16:46:44 +00:00
Chris Lattner 56e5fea163 print target nodes nicely
llvm-svn: 34369
2007-02-17 06:38:37 +00:00
Chris Lattner 68dcec6fea fix indentation
llvm-svn: 34307
2007-02-15 18:19:15 +00:00
Chris Lattner 21ebae3394 Apply B Scott Michel's patch for PR1184, which improves diagnostics in an
abort case.

llvm-svn: 34306
2007-02-15 18:17:56 +00:00
Reid Spencer 09575bac2e For PR1195:
Change use of "packed" term to "vector" in comments, strings, variable
names, etc.

llvm-svn: 34300
2007-02-15 03:39:18 +00:00
Chris Lattner 19083a4671 switch the VRBaseMap in the scheduler from an std::map to a DenseMap. This
speeds up the isel pass from 2.5570s to 2.4722s on kc++ (3.4%).

llvm-svn: 33879
2007-02-04 08:47:20 +00:00
Jim Laskey f9e5445ed4 Make LABEL a builtin opcode.
llvm-svn: 33537
2007-01-26 14:34:52 +00:00
Evan Cheng f5c96fabf9 Renamed getTypeAlignmentShift() to getPreferredTypeAlignmentShift().
llvm-svn: 33482
2007-01-24 07:03:39 +00:00
Evan Cheng be48a47d9d Remove the DoubleTy special case.
llvm-svn: 33449
2007-01-22 23:13:55 +00:00
Reid Spencer a8a0f2cf68 Compensate for loss of DerivedTypes.h in TargetLowering.h
llvm-svn: 33159
2007-01-12 23:31:12 +00:00
Evan Cheng 376c9c4c97 CopyToReg source operand can be a register as well. e.g. Copy from GlobalBaseReg.
llvm-svn: 32929
2007-01-05 20:59:06 +00:00
Bill Wendling 22e978a736 Removing even more <iostream> includes.
llvm-svn: 32320
2006-12-07 20:04:42 +00:00
Evan Cheng 67fc141db5 Match TargetInstrInfo changes.
llvm-svn: 32098
2006-12-01 21:52:58 +00:00
Evan Cheng 20350c4025 Change MachineInstr ctor's to take a TargetInstrDescriptor reference instead
of opcode and number of operands.

llvm-svn: 31947
2006-11-27 23:37:22 +00:00
Evan Cheng dbd3d294e6 Matches MachineInstr changes.
llvm-svn: 31712
2006-11-13 23:36:35 +00:00
Evan Cheng 979bbf48d5 Add methods to add implicit def use operands to a MI.
llvm-svn: 31675
2006-11-11 10:20:02 +00:00
Evan Cheng 8c9c6d71ed Add implicit def / use operands to MachineInstr.
llvm-svn: 31633
2006-11-10 08:43:01 +00:00
Evan Cheng fd2c5dd806 Changes to use operand constraints to process two-address instructions.
llvm-svn: 31453
2006-11-04 09:44:31 +00:00
Chris Lattner 1fd360e13a handle global address constant sdnodes
llvm-svn: 31323
2006-10-31 20:01:56 +00:00
Evan Cheng 47fbeda5ce Debug tweak.
llvm-svn: 30959
2006-10-14 08:34:06 +00:00
Evan Cheng 45fe3bc72c Added support for machine specific constantpool values. These are useful for
representing expressions that can only be resolved at link time, etc.

llvm-svn: 30278
2006-09-12 21:00:35 +00:00
Chris Lattner af23f9b5f6 Completely eliminate def&use operands. Now a register operand is EITHER a
def operand or a use operand.

llvm-svn: 30109
2006-09-05 02:31:13 +00:00
Chris Lattner d86418ab20 switch the SUnit pred/succ sets from being std::sets to being smallvectors.
This reduces selectiondag time on kc++ from 5.43s to 4.98s (9%).  More
significantly, this speeds up the default ppc scheduler from ~1571ms to 1063ms,
a 33% speedup.

llvm-svn: 29743
2006-08-17 00:09:56 +00:00
Evan Cheng 1640ae5a84 Reverse the FlaggedNodes after scanning up for flagged preds or else the order would be reversed.
llvm-svn: 29545
2006-08-07 22:12:12 +00:00
Jim Laskey 4e153f1b91 Use an enumeration to eliminate data relocations.
llvm-svn: 29249
2006-07-21 20:57:35 +00:00
Jim Laskey f7300b2706 It was pointed out that DEBUG() is only available with -debug.
llvm-svn: 29106
2006-07-11 18:25:13 +00:00
Jim Laskey c3d341ea98 Ensure that dump calls that are associated with asserts are removed from
non-debug build.

llvm-svn: 29105
2006-07-11 17:58:07 +00:00
Evan Cheng 55772ccfd6 Instructions with variable operands (variable_ops) can have a number required
operands. e.g.
def CALL32r : I<0xFF, MRM2r, (ops GR32:$dst, variable_ops),
                "call {*}$dst", [(X86call GR32:$dst)]>;
TableGen should emit operand informations for the "required" operands.

Added a target instruction info flag M_VARIABLE_OPS to indicate the target
instruction may have more operands in addition to the minimum required
operands.

llvm-svn: 28791
2006-06-15 07:22:16 +00:00
Evan Cheng 0c0996a97b commuteInstruction() does not always create a new MI!
llvm-svn: 28592
2006-05-31 18:03:39 +00:00
Evan Cheng 9d91caa053 Eliminate a memory leak.
llvm-svn: 28585
2006-05-31 07:13:03 +00:00
Evan Cheng d8e2f6ebc1 lib/Target/Target.td
llvm-svn: 28386
2006-05-18 20:42:07 +00:00
Chris Lattner 957cb6733a Move function-live-in-handling code from the sdisel code to the scheduler.
This code should be emitted after legalize, so it can't be in sdisel.

Note that the EmitFunctionEntryCode hook should be updated to operate on the
DAG.  The X86 backend is the only one currently using this hook.

llvm-svn: 28315
2006-05-16 06:10:58 +00:00
Evan Cheng 99f2f79e2f Fixing 2006-05-01-SchedCausingSpills.ll; some clean up
llvm-svn: 28279
2006-05-13 08:22:24 +00:00
Owen Anderson 8c2c1e90c4 Refactor a bunch of includes so that TargetMachine.h doesn't have to include
TargetData.h.  This should make recompiles a bit faster with my current
TargetData tinkering.

llvm-svn: 28238
2006-05-12 06:33:49 +00:00
Evan Cheng 095c9d9b7f Duh. That could take a long time.
llvm-svn: 28235
2006-05-12 06:05:18 +00:00
Evan Cheng afed73eebe Add capability to scheduler to commute nodes for profit.
If a two-address code whose first operand has uses below, it should be commuted
when possible.

llvm-svn: 28230
2006-05-12 01:58:24 +00:00
Evan Cheng d38c22bdd3 Refactor scheduler code. Move register-reduction list scheduler to a
separate file. Added an initial implementation of top-down register pressure
reduction list scheduler.

llvm-svn: 28226
2006-05-11 23:55:42 +00:00
Chris Lattner 469647bf38 Remove and simplify some more machineinstr/machineoperand stuff.
llvm-svn: 28105
2006-05-04 18:16:01 +00:00
Chris Lattner 10b71c0d08 Rename MO_VirtualRegister -> MO_Register. Clean up immediate handling.
llvm-svn: 28104
2006-05-04 18:05:43 +00:00
Chris Lattner 940cc978ef Remove a bunch more SparcV9 specific stuff
llvm-svn: 28093
2006-05-04 01:15:02 +00:00
Owen Anderson 20a631fde7 Refactor TargetMachine, pushing handling of TargetData into the target-specific subclasses. This has one caller-visible change: getTargetData() now returns a pointer instead of a reference.
This fixes PR 759.

llvm-svn: 28074
2006-05-03 01:29:57 +00:00
Nate Begeman 4ca2ea5b43 JumpTable support! What this represents is working asm and jit support for
x86 and ppc for 100% dense switch statements when relocations are non-PIC.
This support will be extended and enhanced in the coming days to support
PIC, and less dense forms of jump tables.

llvm-svn: 27947
2006-04-22 18:53:45 +00:00
Chris Lattner 87b1dddb1c fix spello
llvm-svn: 27053
2006-03-24 07:15:07 +00:00
Chris Lattner 6b20104410 TargetData doesn't know the alignment of vectors :(
llvm-svn: 26884
2006-03-20 01:51:46 +00:00
Chris Lattner a5b93b8c6d Move some simple-sched-specific instance vars to the simple scheduler.
llvm-svn: 26690
2006-03-10 07:42:02 +00:00
Chris Lattner e015178de1 prune #includes
llvm-svn: 26689
2006-03-10 07:37:35 +00:00
Chris Lattner 4b70ff7876 move some simple scheduler methods into the simple scheduler
llvm-svn: 26688
2006-03-10 07:35:21 +00:00
Chris Lattner dc2f135f5c Make EmitNode take a SDNode instead of a NodeInfo*
llvm-svn: 26687
2006-03-10 07:28:36 +00:00
Chris Lattner b9d8fa0342 Move the VRBase field from NodeInfo to being a separate, explicit, map.
llvm-svn: 26686
2006-03-10 07:25:12 +00:00
Chris Lattner 2f8c7c3d55 Push PrepareNodeInfo/IdentifyGroups down the inheritance hierarchy
llvm-svn: 26682
2006-03-10 06:34:51 +00:00
Chris Lattner 543832d39d Change the interface for getting a target HazardRecognizer to be more clean.
llvm-svn: 26608
2006-03-08 04:25:59 +00:00
Chris Lattner 2d945ba4c7 When a hazard recognizer needs noops to be inserted, do so. This represents
noops as null pointers in the instruction sequence.

llvm-svn: 26564
2006-03-05 23:51:47 +00:00
Evan Cheng ed169db8a5 Added an offset field to ConstantPoolSDNode.
llvm-svn: 26371
2006-02-25 09:54:52 +00:00
Chris Lattner 5af3fdec12 Pass all the flags to the asm printer, not just the # operands.
llvm-svn: 26362
2006-02-24 19:50:58 +00:00
Chris Lattner 2f8a794b13 rename NumOps -> NumVals to avoid shadowing a NumOps var in an outer scope.
Add support for addressing modes.

llvm-svn: 26361
2006-02-24 19:18:20 +00:00
Chris Lattner 86c51000db Refactor operand adding out to a new AddOperand method
llvm-svn: 26358
2006-02-24 18:54:03 +00:00
Chris Lattner 571d9647c6 Record all of the expanded registers in the DAG and machine instr, fixing
several bugs in inline asm expanded operands.

llvm-svn: 26332
2006-02-23 19:21:04 +00:00
Chris Lattner 4576bb74d5 Make MachineConstantPool entries alignments explicit
llvm-svn: 26071
2006-02-09 02:23:13 +00:00
Jeff Cohen 95ae171d5b Fix VC++ warning.
llvm-svn: 25975
2006-02-04 16:20:31 +00:00
Evan Cheng f9adce90bf Get rid of some memory leaks identified by Valgrind
llvm-svn: 25960
2006-02-04 06:49:00 +00:00
Chris Lattner 3b48431333 Add initial support for immediates. This allows us to compile this:
int %rlwnm(int %A, int %B) {
  %C = call int asm "rlwnm $0, $1, $2, $3, $4", "=r,r,r,n,n"(int %A, int %B, int 4, int 17)
  ret int %C
}

into:

_rlwnm:
        or r2, r3, r3
        or r3, r4, r4
        rlwnm r2, r2, r3, 4, 17    ;; note the immediates :)
        or r3, r2, r2
        blr

llvm-svn: 25955
2006-02-04 02:26:14 +00:00
Evan Cheng 32be2dc0af Allow the specification of explicit alignments for constant pool entries.
llvm-svn: 25855
2006-01-31 22:23:14 +00:00
Chris Lattner 2e56e89452 Handle physreg input/outputs. We now compile this:
int %test_cpuid(int %op) {
        %B = alloca int
        %C = alloca int
        %D = alloca int
        %A = call int asm "cpuid", "=eax,==ebx,==ecx,==edx,eax"(int* %B, int* %C, int* %D, int %op)
        %Bv = load int* %B
        %Cv = load int* %C
        %Dv = load int* %D
        %x = add int %A, %Bv
        %y = add int %x, %Cv
        %z = add int %y, %Dv
        ret int %z
}

to this:

_test_cpuid:
        sub %ESP, 16
        mov DWORD PTR [%ESP], %EBX
        mov %EAX, DWORD PTR [%ESP + 20]
        cpuid
        mov DWORD PTR [%ESP + 8], %ECX
        mov DWORD PTR [%ESP + 12], %EBX
        mov DWORD PTR [%ESP + 4], %EDX
        mov %ECX, DWORD PTR [%ESP + 12]
        add %EAX, %ECX
        mov %ECX, DWORD PTR [%ESP + 8]
        add %EAX, %ECX
        mov %ECX, DWORD PTR [%ESP + 4]
        add %EAX, %ECX
        mov %EBX, DWORD PTR [%ESP]
        add %ESP, 16
        ret

... note the proper register allocation.  :)

it is unclear to me why the loads aren't folded into the adds.

llvm-svn: 25827
2006-01-31 02:03:41 +00:00
Chris Lattner 4df279cfda Teach the scheduler to emit the appropriate INLINEASM MachineInstr for an
ISD::INLINEASM node.

llvm-svn: 25668
2006-01-26 23:28:04 +00:00
Evan Cheng 1880f8db02 No need to keep track of top and bottom nodes in a group since the vector is
already in order. Thanks Jim for pointing it out.

llvm-svn: 25608
2006-01-25 18:54:24 +00:00
Evan Cheng fbc88a624a Keep track of bottom / top element of a set of flagged nodes.
llvm-svn: 25600
2006-01-25 09:13:41 +00:00