Commit Graph

60 Commits

Author SHA1 Message Date
Dan Gohman
5034dd318a Move Value::getUnderlyingObject to be a standalone
function so that it can live in Analysis instead of
VMCore.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121885 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-15 20:02:24 +00:00
Evan Cheng
8239daf7c8 Two sets of changes. Sorry they are intermingled.
1. Fix pre-ra scheduler so it doesn't try to push instructions above calls to
   "optimize for latency". Call instructions don't have the right latency and
   this is more likely to use introduce spills.
2. Fix if-converter cost function. For ARM, it should use instruction latencies,
   not # of micro-ops since multi-latency instructions is completely executed
   even when the predicate is false. Also, some instruction will be "slower"
   when they are predicated due to the register def becoming implicit input.
   rdar://8598427


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118135 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-03 00:45:17 +00:00
Evan Cheng
de5fa932b9 Putting r117193 back except for the compile time cost. Rather than assuming fallthroughs uses all registers, just gather the union of all successor liveins.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117506 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-27 23:17:17 +00:00
Evan Cheng
38fd9f2a2d Neuter r117193 as it causes significant post-ra scheduler compile time regression.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117329 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-25 23:56:21 +00:00
Evan Cheng
ec6906ba47 Properly model the latency of register defs which are 1) function returns or
2) live-outs.

Previously the post-RA schedulers completely ignore these dependencies since
returns, branches, etc. are all scheduling barriers. This patch model the
latencies between instructions being scheduled and the barriers. It also
handle calls by marking their register uses.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117193 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-23 02:10:46 +00:00
Evan Cheng
d82de8341c Avoid compiler warning: comparison between signed and unsigned integer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116119 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-08 23:01:57 +00:00
Evan Cheng
1aca5bc135 Fix operand latency computation in cases where the definition operand is
implicit. e.g.
%D6<def>, %D7<def> = VLD1q16 %R2<kill>, 0, ..., %Q3<imp-def>                                                                                                                                                                              
%Q1<def> = VMULv8i16 %Q1<kill>, %Q3<kill>, ...

The real definition indices are 0,1.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116080 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-08 18:42:25 +00:00
Nick Lewycky
9c220fc165 Remove unused variables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115802 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-06 18:11:50 +00:00
Evan Cheng
a0792de66c - Add TargetInstrInfo::getOperandLatency() to compute operand latencies. This
allow target to correctly compute latency for cases where static scheduling
  itineraries isn't sufficient. e.g. variable_ops instructions such as
  ARM::ldm.
  This also allows target without scheduling itineraries to compute operand
  latencies. e.g. X86 can return (approximated) latencies for high latency
  instructions such as division.
- Compute operand latencies for those defined by load multiple instructions,
  e.g. ldm and those used by store multiple instructions, e.g. stm.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115755 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-06 06:27:31 +00:00
Evan Cheng
3881cb7a5d Model Cortex-a9 load to SUB, RSB, ADD, ADC, SBC, RSC, CMN, MVN, or CMP
pipeline forwarding path.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115098 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-29 22:42:35 +00:00
Evan Cheng
3ef1c8759a Teach if-converter to be more careful with predicating instructions that would
take multiple cycles to decode.
For the current if-converter clients (actually only ARM), the instructions that
are predicated on false are not nops. They would still take machine cycles to
decode. Micro-coded instructions such as LDM / STM can potentially take multiple
cycles to decode. If-converter should take treat them as non-micro-coded
simple instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113570 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-10 01:29:16 +00:00
Bob Wilson
f28dd88611 Change ScheduleDAGInstrs::Defs and ::Uses to be variable-size vectors
instead of fixed size arrays, so that increasing FirstVirtualRegister to 16K
won't cause a compile time performance regression.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109330 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-24 06:01:53 +00:00
Bill Wendling
87ea294b0d Use std::vector instead of TargetRegisterInfo::FirstVirtualRegister.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108452 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-15 20:04:36 +00:00
Jim Grosbach
309d20c89c Fix the post-RA instruction scheduler to handle instructions referenced by
more than one dbg_value instruction. rdar://7759363


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104174 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-19 22:57:06 +00:00
Dan Gohman
af1d8ca44a Get rid of the EdgeMapping map. Instead, just check for BasicBlock
changes before doing phi lowering for switches.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102809 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-01 00:01:06 +00:00
Dan Gohman
3fb150a902 Fix -Wcast-qual warnings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101655 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-17 17:42:52 +00:00
Evan Cheng
a69ec09364 Reduce indentation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99214 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-22 21:24:33 +00:00
Evan Cheng
fc91114a2e 80 col violation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99195 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-22 18:40:50 +00:00
Dale Johannesen
bfdf7f3852 Progress towards shepherding debug info through SelectionDAG.
No functional effect yet.  This is still evolving and should
not be viewed as final.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98195 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-10 22:13:47 +00:00
Duncan Sands
1df9859c40 There are two ways of checking for a given type, for example isa<PointerType>(T)
and T->isPointerTy().  Convert most instances of the first form to the second form.
Requested by Chris.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96344 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-16 11:11:14 +00:00
David Goodwin
980d494ab6 Fix dependencies added to model memory aliasing for post-RA scheduling. The dependencies were overly conservative for memory access that are known not to alias.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86580 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-09 19:22:17 +00:00
David Goodwin
5be870add9 Correctly add chain dependencies around calls and unknown-side-effect instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86080 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-05 00:16:44 +00:00
David Goodwin
a9e610768b <rdar://problem/7352605>. When building schedule graph use mayAlias information to avoid chaining loads/stores of spill slots with non-aliased memory ops.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85934 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-03 20:15:00 +00:00
David Goodwin
7c9b1ac507 Chain dependencies used to enforce memory order should have latency of 0 (except for true dependency of Store followed by aliased Load... we estimate that case with a single cycle of latency assuming the hardware will bypass)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85807 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-02 17:06:28 +00:00
Dan Gohman
91203cf87b When checking whether a def of an aliased register is dead, ask the
machineinstr whether the aliased register is dead, rather than the original
register is dead. This allows it to get the correct answer when examining
an instruction like this:
  CALLpcrel32 <ga:foo>, %AL<imp-def>, %EAX<imp-def,dead>
where EAX is dead but a subregister of it is still live. This fixes PR5294.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85135 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-26 18:26:18 +00:00
Evan Cheng
38bdfc69cb Spill slots cannot alias.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84432 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-18 19:58:47 +00:00
Evan Cheng
ff89dcb06f -Revert parts of 84326 and 84411. Distinquishing between fixed and non-fixed
stack slots and giving them different PseudoSourceValue's did not fix the
problem of post-alloc scheduling miscompiling llvm itself.
- Apply Dan's conservative workaround by assuming any non fixed stack slots can
alias other memory locations. This means a load from spill slot #1 cannot 
move above a store of spill slot #2. 
- Enable post-alloc scheduling for x86 at optimization leverl Default and above.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84424 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-18 18:16:27 +00:00
Dan Gohman
a70dca156f Factor out LiveIntervalAnalysis' code to determine whether an instruction
is trivially rematerializable and integrate it into
TargetInstrInfo::isTriviallyReMaterializable. This way, all places that
need to know whether an instruction is rematerializable will get the
same answer.

This enables the useful parts of the aggressive-remat option by
default -- using AliasAnalysis to determine whether a memory location
is invariant, and removes the questionable parts -- rematting operations
with virtual register inputs that may not be live everywhere.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83687 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-09 23:27:56 +00:00
Dan Gohman
e33f44cfc5 Replace TargetInstrInfo::isInvariantLoad and its target-specific
implementations with a new MachineInstr::isInvariantLoad, which uses
MachineMemOperands and is target-independent. This brings MachineLICM
and other functionality to targets which previously lacked an
isInvariantLoad implementation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83475 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-07 17:38:06 +00:00
Dan Gohman
c76909abfe Improve MachineMemOperand handling.
- Allocate MachineMemOperands and MachineMemOperand lists in MachineFunctions.
   This eliminates MachineInstr's std::list member and allows the data to be
   created by isel and live for the remainder of codegen, avoiding a lot of
   copying and unnecessary translation. This also shrinks MemSDNode.
 - Delete MemOperandSDNode. Introduce MachineSDNode which has dedicated
   fields for MachineMemOperands.
 - Change MemSDNode to have a MachineMemOperand member instead of its own
   fields with the same information. This introduces some redundancy, but
   it's more consistent with what MachineInstr will eventually want.
 - Ignore alignment when searching for redundant loads for CSE, but remember
   the greatest alignment.

Target-specific code which previously used MemOperandSDNodes with generic
SDNodes now use MemIntrinsicSDNodes, with opcodes in a designated range
so that the SelectionDAG framework knows that MachineMemOperand information
is available.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82794 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-25 20:36:54 +00:00
Evan Cheng
fb2e752e41 Enhance EmitInstrWithCustomInserter() so target can specify CFG changes that sdisel will use to properly complete phi nodes.
Not functionality change yet.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82273 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-18 21:02:19 +00:00
David Goodwin
dc4bdcdef1 Use the schedule itinerary operand use/def cycle information to adjust dependence edge latency for post-RA scheduling.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79425 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-19 16:08:58 +00:00
David Goodwin
710461688b Add callback to allow target to adjust latency of schedule dependency edge.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78910 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-13 16:05:04 +00:00
David Goodwin
d94a4e5d8d Post RA scheduler changes. Introduce a hazard recognizer that uses the target schedule information to accurately model the pipeline. Update the scheduler to correctly handle multi-issue targets.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78563 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-10 15:55:25 +00:00
Dan Gohman
748f98f908 Fix a typo in a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78362 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-07 01:26:06 +00:00
Dan Gohman
8906f95006 Eliminate yet another copy of getOpcode.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76236 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-17 20:58:59 +00:00
Dan Gohman
16a2c927e9 Move isLCSSAForm, isLoopInvariant, getCanonicalInductionVariable,
and related functions out of LoopBase and into Loop, since they
are specific to BasicBlock-based loops. This also allows the code
to be moved out-of-line.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75523 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-13 22:02:44 +00:00
Dan Gohman
47ac0f0c7c 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64288 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-11 04:27:20 +00:00
Dan Gohman
9e64bbb322 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64254 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-10 23:27:53 +00:00
Dan Gohman
6dc75fe527 Move ScheduleDAGInstrs.h to be a private header. Front-ends
that used this header to select a scheduling policy should
use SchedulerRegistry.h instead (llvm-gcc and clang were
updated a while ago).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63934 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-06 17:12:10 +00:00
Dan Gohman
3311a1f8f0 Fix a post-RA scheduling dependency bug.
If a MachineInstr doesn't have a memoperand but has an opcode that
is known to load or store, assume its memory reference may alias
*anything*, including stack slots which the compiler completely
controls.

To partially compensate for this, teach the ScheduleDAG building
code to do basic getUnderlyingValue analysis. This greatly
reduces the number of instructions that require restrictive
dependencies. This code will need to be revisited when we start
doing real alias analysis, but it should suffice for now.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63370 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-30 02:49:14 +00:00
Dan Gohman
f7119393a9 Instead of adding dependence edges between terminator instructions
and every other instruction in their blocks to keep the terminator
instructions at the end, teach the post-RA scheduler how to operate
on ranges of instructions, and exclude terminators from the range
of instructions that get scheduled.

Also, exclude mid-block labels, such as EH_LABEL instructions, and
schedule code before them separately from code after them. This
fixes problems with the post-RA scheduler moving code past
EH_LABELs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62366 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-16 22:10:20 +00:00
Dan Gohman
79ce276083 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62275 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-15 19:20:50 +00:00
Dan Gohman
0b1d4a798d Clean up the atomic opcodes in SelectionDAG.
This removes all the _8, _16, _32, and _64 opcodes and replaces each
group with an unsuffixed opcode. The MemoryVT field of the AtomicSDNode
is now used to carry the size information. In tablegen, the size-specific
opcodes are replaced by size-independent opcodes that utilize the
ability to compose them with predicates.

This shrinks the per-opcode tables and makes the code that handles
atomics much more concise.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61389 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-23 21:37:04 +00:00
Dan Gohman
c9a5b9e38b Rename BuildSchedUnits to BuildSchedGraph, and refactor the
code in ScheduleDAGSDNodes' BuildSchedGraph into separate functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61376 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-23 18:36:58 +00:00
Dan Gohman
237dee1259 Use isTerminator() instead of isBranch()||isReturn() in
several places. isTerminator() returns true for a superset
of cases, and includes things like FP_REG_KILL, which are
nither return or branch but aren't safe to move/remat/etc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61373 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-23 17:28:50 +00:00
Dan Gohman
8749b61178 Add initial support for back-scheduling address computations,
especially in the case of addresses computed from loop induction
variables.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61075 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 03:35:01 +00:00
Dan Gohman
3f23744df4 Fix some register-alias-related bugs in the post-RA scheduler liveness
computation code. Also, avoid adding output-depenency edges when both
defs are dead, which frequently happens with EFLAGS defs.

Compute Depth and Height lazily, and always in terms of edge latency
values. For the schedulers that don't care about latency, edge latencies
are set to 1.

Eliminate Cycle and CycleBound, and LatencyPriorityQueue's Latencies array.
These are all subsumed by the Depth and Height fields.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61073 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 03:25:46 +00:00
Dan Gohman
4ea8e85e19 Add a simple target-independent heuristic to allow targets with no
instruction itinerary data to back-schedule loads.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61070 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 02:38:22 +00:00
Dan Gohman
54e4c36a73 Rewrite the SDep class, and simplify some of the related code.
The Cost field is removed. It was only being used in a very limited way,
to indicate when the scheduler should attempt to protect a live register,
and it isn't really needed to do that. If we ever want the scheduler to
start inserting copies in non-prohibitive situations, we'll have to
rethink some things anyway.

A Latency field is added. Instead of giving each node a single
fixed latency, each edge can have its own latency. This will eventually
be used to model various micro-architecture properties more accurately.

The PointerIntPair class and an internal union are now used, which
reduce the overall size.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60806 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-09 22:54:47 +00:00