Commit Graph

3451 Commits

Author SHA1 Message Date
Hal Finkel
fa1d102a05 PPC pre-increment load instructions do not have side effects
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178972 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-07 05:46:58 +00:00
Hal Finkel
aecbe24268 PPC MCRF instruction does not have side effects
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178971 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-07 05:16:57 +00:00
Hal Finkel
fa1cac2a1e PPC FMR instruction does not have side effects
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178970 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-07 04:56:16 +00:00
Hal Finkel
839b909653 Implement PPCInstrInfo::FoldImmediate
There are certain PPC instructions into which we can fold a zero immediate
operand. We can detect such cases by looking at the register class required
by the using operand (so long as it is not otherwise constrained).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178961 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-06 19:30:30 +00:00
Hal Finkel
012ffd5605 PPC ISEL is a select and never has side effects
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178960 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-06 19:30:28 +00:00
Hal Finkel
ff56d1a201 Enable early if conversion on PPC
On cores for which we know the misprediction penalty, and we have
the isel instruction, we can profitably perform early if conversion.
This enables us to replace some small branch sequences with selects
and avoid the potential stalls from mispredicting the branches.

Enabling this feature required implementing canInsertSelect and
insertSelect in PPCInstrInfo; isel code in PPCISelLowering was
refactored to use these functions as well.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178926 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05 23:29:01 +00:00
Hal Finkel
de80951ae9 Correct the PPC A2 misprediction penalty
The manual states that there is a minimum of 13 cycles from when the
mispredicted branch is issued to when the correct branch target is
issued.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178925 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05 23:28:58 +00:00
Hal Finkel
1abaf907b6 Add a SchedMachineModel for the PPC G5
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178850 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05 05:49:18 +00:00
Hal Finkel
575e9229bd Add a SchedMachineModel for the PPC A2
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178848 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-05 05:34:08 +00:00
Arnold Schwaighofer
6bf4f67641 CostModel: Add parameter to instruction cost to further classify operand values
On certain architectures we can support efficient vectorized version of
instructions if the operand value is uniform (splat) or a constant scalar.
An example of this is a vector shift on x86.

We can efficiently support

for (i = 0 ; i < ; i += 4)
  w[0:3] = v[0:3] << <2, 2, 2, 2>

but not

for (i = 0; i < ; i += 4)
  w[0:3] = v[0:3] << x[0:3]

This patch adds a parameter to getArithmeticInstrCost to further qualify operand
values as uniform or uniform constant.

Targets can then choose to return a different cost for instructions with such
operand values.

A follow-up commit will test this feature on x86.

radar://13576547

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178807 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-04 23:26:21 +00:00
Hal Finkel
caeeb18650 Rename the current PPC BCL definition to BCLalways
BCL is normally a conditional branch-and-link instruction, but has
an unconditional form (which is used in the SjLj code, for example).
To make clear that this BCL instruction definition is specifically
the special unconditional form (which does not meaningfully take
a condition-register input), rename it to BCLalways.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178803 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-04 22:55:54 +00:00
Hal Finkel
7530a9f7d1 PPC: Improve code generation for mixed-precision reciprocal sqrt
The DAGCombine logic that recognized a/sqrt(b) and transformed it into
a multiplication by the reciprocal sqrt did not handle cases where the
sqrt and the division were separated by an fpext or fptrunc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178801 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-04 22:44:12 +00:00
Hal Finkel
63c32a7a9f Cleanup PPC reciprocal-estimate functionality
Incorporating review feedback from Bill Schmidt on r178617. No functionality
change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178672 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03 17:44:56 +00:00
Hal Finkel
110e323b61 PPC: Enable FRES and FRSQRTE on the default PPC64 description
I discussed this with Bill Schmidt on IRC, and it was decided that this is a
safe and reasonable default.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178659 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03 14:40:18 +00:00
Hal Finkel
7d52a41e32 PPC: Add a FIXME regarding the non-working fma+fneg Altivec pattern
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178658 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03 14:40:16 +00:00
Hal Finkel
d8f8f58476 Remove some obsolete PowerPC/README entries
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178657 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03 14:25:55 +00:00
Ulrich Weigand
6b9d52eefd More direct types in PowerPC AltiVec intrinsics.
This patch follows up on work done by Bill Schmidt in r178277,
and replaces most of the remaining uses of VRRC in ISEL DAG patterns.

The resulting .inc files are identical except for comments, so
no change in code generation is expected.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178656 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03 14:08:13 +00:00
Bill Schmidt
cd7a1558ed Fix PR15632: No support for ppcf128 floating-point remainder on PowerPC.
For this we need to use a libcall.  Previously LLVM didn't implement
libcall support for frem, so I've added it in the usual
straightforward manner.  A test case from the bug report is included.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178639 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03 13:05:44 +00:00
Hal Finkel
2d8f62017d Remove some unsupported-feature comments from PPC.td
These refer to the reciprocal estimate support recently committed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178618 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03 04:03:58 +00:00
Hal Finkel
827307b95f Use PPC reciprocal estimates with Newton iteration in fast-math mode
When unsafe FP math operations are enabled, we can use the fre[s] and
frsqrte[s] instructions, which generate reciprocal (sqrt) estimates, together
with some Newton iteration, in order to quickly generate floating-point
division and sqrt results. All of these instructions are separately optional,
and so each has its own feature flag (except for the Altivec instructions,
which are covered under the existing Altivec flag). Doing this is not only
faster than using the IEEE-compliant fdiv/fsqrt instructions, but allows these
computations to be pipelined with other computations in order to hide their
overall latency.

I've also added a couple of missing fnmsub patterns which turned out to be
missing (but are necessary for good code generation of the Newton iterations).
Altivec needs a similar fix, but that will probably be more complicated because
fneg is expanded for Altivec's v4f32.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178617 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03 04:01:11 +00:00
Bill Schmidt
debf7d345a Fix PR15630: Replace faulty stdcx. with stwcx.
When doing a partword atomic operation, a lwarx was being paired with
a stdcx. instead of a stwcx. when compiling for a 64-bit target.  The
target has nothing to do with it in this case; we always need a stwcx.

Thanks to Kai Nacke for reporting the problem.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178559 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-02 18:37:08 +00:00
Hal Finkel
2a401959b9 Fix typo in PPCISelLowering
Thanks to Bill Schmidt for finding this in review of r178480.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178521 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-02 03:29:51 +00:00
Hal Finkel
a1646ceb9a Fix a bad assert in PPCTargetLowering
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178489 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-01 18:42:58 +00:00
Hal Finkel
4647919784 Add more PPC floating-point conversion instructions
The P7 and A2 have additional floating-point conversion instructions which
allow a direct two-instruction sequence (plus load/store) to convert from all
combinations (signed/unsigned i32/i64) <--> (float/double) (on previous cores,
only some combinations were directly available).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178480 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-01 17:52:07 +00:00
Hal Finkel
a1f4290ac9 Use ImmToIdxMap.count in PPCRegisterInfo
Code improvement suggested by Jakob (in review of r178450). No functionality
change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178473 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-01 17:02:06 +00:00
Hal Finkel
1fce88313e Add the PPC popcntw instruction
The popcntw instruction is available whenever the popcntd instruction is
available, and performs a separate popcnt on the lower and upper 32-bits.
Ignoring the high-order count, this can be used for the 32-bit input case
(saving on the explicit zero extension otherwise required to use popcntd).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178470 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-01 15:58:15 +00:00
Hal Finkel
f170cc9b2e Treat PPCISD::STFIWX like the memory opcode that it is
PPCISD::STFIWX is really a memory opcode, and so it should come after
FIRST_TARGET_MEMORY_OPCODE, and we should use DAG.getMemIntrinsicNode to create
nodes using it.

No functionality change intended (although there could be optimization benefits
from preserving the MMO information).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178468 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-01 15:37:53 +00:00
Hal Finkel
4345e8040f Cleanup ImmToIdxMap and noImmForm in PPCRegisterInfo
ImmToIdxMap should be a DenseMap (not a std::map) because there
is no ordering requirement. Also, we don't need a separate list
of instructions for noImmForm in eliminateFrameIndex, because this
list is essentially the complement of the keys in ImmToIdxMap.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178450 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-31 14:43:31 +00:00
Hal Finkel
8049ab15e4 Add the PPC lfiwax instruction
This instruction is available on modern PPC64 CPUs, and is now used
to improve the SINT_TO_FP lowering (by eliminating the need for the
separate sign extension instruction and decreasing the amount of
needed stack space).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178446 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-31 10:12:51 +00:00
Hal Finkel
9ad0f4907b Cleanup PPC(64) i32 -> float/double conversion
The existing SINT_TO_FP code for i32 -> float/double conversion was disabled
because it relied on broken EXTSW_32/STD_32 instruction definitions. The
original intent had been to enable these 64-bit instructions to be used on CPUs
that support them even in 32-bit mode.  Unfortunately, this form of lying to
the infrastructure was buggy (as explained in the FIXME comment) and had
therefore been disabled.

This re-enables this functionality, using regular DAG nodes, but only when
compiling in 64-bit mode. The old STD_32/EXTSW_32 definitions (which were dead)
are removed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178438 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-31 01:58:02 +00:00
Hal Finkel
0882fd6c4f Implement FRINT lowering on PPC using frin
Like nearbyint, rint can be implemented on PPC using the frin instruction. The
complication comes from the fact that rint needs to set the FE_INEXACT flag
when the result does not equal the input value (and frin does not do that). As
a result, we use a custom inserter which, after the rounding, compares the
rounded value with the original, and if they differ, explicitly sets the XX bit
in the FPSCR register (which corresponds to FE_INEXACT).

Once LLVM has better modeling of the floating-point environment we should be
able to (often) eliminate this extra complexity.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178362 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-29 19:41:55 +00:00
Benjamin Kramer
74a4533a42 Remove the old CodePlacementOpt pass.
It was superseded by MachineBlockPlacement and disabled by default since LLVM 3.1.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178349 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-29 17:14:24 +00:00
Hal Finkel
f5d5c43460 Add PPC FP rounding instructions fri[mnpz]
These instructions are available on the P5x (and later) and on the A2. They
implement the standard floating-point rounding operations (floor, trunc, etc.).
One caveat: frin (round to nearest) does not implement "ties to even", and so
is only enabled in fast-math mode.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178337 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-29 08:57:48 +00:00
Hal Finkel
2544f221c5 Only enable 64-bit bswap DAG combines for PPC64
Compiling in 32-bit mode on a P7 would assert after 64-bit DAG combines were
added for bswap with load/store. This is because these combines are really only
valid in 64-bit mode, regardless of the CPU (and this was not being checked).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178286 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28 20:23:46 +00:00
Hal Finkel
b52980be07 Fix bad indentation in r178276
Thanks to Bill Schmidt for pointing this out!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178280 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28 19:43:12 +00:00
Bill Schmidt
53774a821d Use direct types in most PowerPC Altivec instructions and patterns.
This follows up Ulrich Weigand's work in PPCInstrInfo.td and
PPCInstr64Bit.td by doing the corresponding work for most of the
Altivec patterns.  I have not been able to do anything for the
following classes of instructions:

(1) Vector logicals.  These don't have corresponding intrinsics and
don't have a single obvious vector type.  So far as I can tell I need
to leave these as VRRC.  Affected instructions are:  VAND, VANDC,
VNOR, VOR, VXOR, V_SET0.

(2) Instructions that make use of vector shuffle.  The selection code
promotes all shuffles to v16i8, so any pattern that matches on a
shuffle is constrained.  I haven't found any way to make the patterns
match on their natural types, so I plan to leave these as VRRC.
Affected instructions are:  VMRG*, VSPLTB, VSPLTH, VSPLTW, VPKUHUM,
VPKUWUM.

No change in behavior is anticipated.




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178277 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28 19:27:24 +00:00
Hal Finkel
efdd4673d6 Add the PPC64 ldbrx/stdbrx instructions
These are 64-bit load/store with byte-swap, and available on the P7 and the A2.
Like the similar instructions for 16- and 32-bit words, these are matched in the
target DAG-combine phase against load/store-bswap pairs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178276 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28 19:25:55 +00:00
Hal Finkel
c53ab4d77f Add the PPC64 popcntd instruction
PPC ISA 2.06 (P7, A2, etc.) has a popcntd instruction. Add this instruction and
tell TTI about it so that popcount-loop recognition will know about it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178233 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28 13:29:47 +00:00
Hal Finkel
d957f957ee Cleanup PPC CR-spill kill flags and 32- vs. 64-bit instructions
There were a few places where kill flags were not being set correctly, and
where 32-bit instruction variants were being used with 64-bit registers. After
r178180, this code was being triggered causing llc to assert.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178220 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28 03:38:16 +00:00
Hal Finkel
d01efc737a Fix typo in PPCInstr64Bit
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178219 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28 03:38:08 +00:00
Hal Finkel
f25f93b685 Resynchronize isLoadFromStackSlot with LoadRegFromStackSlot (and stores) in PPCInstrInfo
These functions should have the same list of load/store instructions. Now that
all load/store forms have been normalized (to single instructions or pseudos)
they can be resynchronized.

Found by inspection, although hopefully this will improve optimization.  I've
also added some comments.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178180 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 21:21:15 +00:00
Hal Finkel
e915047fed Fix typo (common to both X86 and PPC)
Thanks to Bill Schmidt for pointing this out during code review!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178170 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 19:10:42 +00:00
Hal Finkel
fc80586968 Remove more dead LR-as-GPR PPC code
I had removed similar code a few days ago, but somehow missed this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178169 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 19:10:40 +00:00
Hal Finkel
e77918c355 Remove "gpr0 allocation" from the PPC README TODO list
As Chris pointed out, post r178123, this is now done!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178165 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 18:39:52 +00:00
Hal Finkel
32e12df253 Print PPC ZERO as 0 (not r0) even on Darwin
It seems that the Darwin PPC assembler requires r0 to be written as 0 when it
means 0 (at least in lwarx/stwcx.). Fixes PR15605.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178142 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 13:20:52 +00:00
Hal Finkel
240b7f3324 Allocate r0 on PPC
The R0 register can now be allocated because instructions
that cannot use R0 as a GPR have been appropriately marked.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178123 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 06:52:27 +00:00
Hal Finkel
6375e1b87b Use the PPC no-r0 class on the TOC LD pseudos
The register parameter in these instructions becomes the base register in an
r+i ld instruction (and, thus, cannot be r0).

This is not yet testable because we don't yet allocate r0 (and even then any
test would be very fragile).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178121 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 06:36:55 +00:00
Hal Finkel
ab42ec2586 Apply the no-r0 register class to the PPC SELECT_CC_I[4|8] pseudos
Either operand of these pseudo instructions can be transformed into the first
operand of an isel instruction (and this operand cannot be r0).

This is not yet testable because we don't yet allocate r0 (and even when we do,
any test would be very fragile).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178119 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 05:57:58 +00:00
Hal Finkel
56d926ac14 Apply the no-r0 class to PPC TOC ADDI[S] pseudo instructions
Like the addi/addis instructions themselves, these pseudo instructions also
cannot have r0 as their register parameter (because it will be interpreted as
the value 0).

This is not yet testable because we don't yet allocate r0 (and even when we do,
any regression test would be very fragile because it would depend on the
register allocator heuristics).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178118 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 05:57:56 +00:00
Bill Schmidt
37ef805818 Remove the link register from the GPR classes on PowerPC.
Some implementation detail in the forgotten past required the link
register to be placed in the GPRC and G8RC register classes.  This is
just wrong on the face of it, and causes several extra intersection
register classes to be generated.  I found this was having evil
effects on instruction scheduling, by causing the wrong register class
to be consulted for register pressure decisions.

No code generation changes are expected, other than some minor changes
in instruction order.  Seven tests in the test bucket required minor
tweaks to adjust to the new normal.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178114 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 02:40:14 +00:00
Hal Finkel
b7e11e400d Don't spill PPC VRSAVE on non-Darwin (even in SjLj)
As Bill Schmidt pointed out to me, only on Darwin do we need to spill/restore
VRSAVE in the SjLj code. For non-Darwin, don't spill/restore VRSAVE (and I've
added some asserts to make sure that we're not).

As it turns out, we're not currently handling the Darwin case correctly (I've
added a FIXME in the test case). I've tried adding various implied register
definitions/uses to force the spill without success, so I'll need to address
this later.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178096 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 00:02:20 +00:00
Hal Finkel
1a0034c74a Restore real bit lengths on PPC register numbers
As suggested by Bill Schmidt (in reviewing r178067), use the real register
number bit lengths (which is self-documenting, and prevents using illegal
numbers), and set only the relevant bits in HWEncoding (which defaults to 0).

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178077 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 21:50:26 +00:00
Hal Finkel
aa6047d23d PPC: Use HWEncoding and TRI->getEncodingValue
As pointed out by Jakob, we don't need to maintain a separate
register-numbering table. Instead we should let TableGen generate the table for
us from the information (already present) in PPCRegisterInfo.td.
TRI->getEncodingValue is now used to access register-encoding values.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178067 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 20:08:20 +00:00
Hal Finkel
01f99d29c3 Use multiple virtual registers in PPC CR spilling
Now that the register scavenger can support multiple spill slots, and PEI can
use virtual-register-based scavenging for multiple simultaneous registers, we
can use a virtual register for the transfer register in the CR spilling code.

This should eliminate the last place (outside of the prologue/epilogue) where
we depend on the unconditional availability of the r0 register. We will soon be
able to allocate it (in a somewhat restricted sense) as a GPR.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178060 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 18:57:22 +00:00
Hal Finkel
3b196f20fb Update PPCRegisterInfo's use of virtual registers to be SSA
PPC's use of PEI's virtual-register-based scavenging functionality had
redefined the virtual registers (it was non-SSA). Now that PEI supports
dealing with instructions with multiple virtual registers, this can be
cleanup up to use multiple virtual registers and keep SSA form.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178059 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 18:57:20 +00:00
Benjamin Kramer
d6f5a581ab Remove default case from fully covered switch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178025 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 14:17:42 +00:00
Ulrich Weigand
3d386421e0 PowerPC: Mark patterns as isCodeGenOnly.
There remain a number of patterns that cannot (and should not)
be handled by the asm parser, in particular all the Pseudo patterns.

This commit marks those patterns as isCodeGenOnly.

No change in generated code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178008 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:57:16 +00:00
Ulrich Weigand
65e90c0364 PowerPC: Simplify handling of fixups.
MCTargetDesc/PPCMCCodeEmitter.cpp current has code like:

 if (isSVR4ABI() && is64BitMode())
   Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
                                    (MCFixupKind)PPC::fixup_ppc_toc16));
 else
   Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
                                    (MCFixupKind)PPC::fixup_ppc_lo16));

This is a problem for the asm parser, since it requires knowledge of
the ABI / 64-bit mode to be set up.  However, more fundamentally,
at this point we shouldn't make such distinctions anyway; in an assembler
file, it always ought to be possible to e.g. generate TOC relocations even
when the main ABI is one that doesn't use TOC.

Fortunately, this is actually completely unnecessary; that code was added
to decide whether to generate TOC relocations, but that information is in
fact already encoded in the VariantKind of the underlying symbol.

This commit therefore merges those fixup types into one, and then decides
which relocation to use based on the VariantKind.

No changes in generated code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178007 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:56:47 +00:00
Ulrich Weigand
7d35d3f432 PowerPC: Simplify FADD in round-to-zero mode.
As part of the the sequence generated to implement long double -> int
conversions, we need to perform an FADD in round-to-zero mode.  This is
problematical since the FPSCR is not at all modeled at the SelectionDAG
level, and thus there is a risk of getting floating point instructions
generated out of sequence with the instructions to modify FPSCR.

The current code handles this by somewhat "special" patterns that in part
have dummy operands, and/or duplicate existing instructions, making them
awkward to handle in the asm parser.

This commit changes this by leaving the "FADD in round-to-zero mode"
as an atomic operation on the SelectionDAG level, and only split it up into
real instructions at the MI level (via custom inserter).  Since at *this*
level the FPSCR *is* modeled (via the "RM" hard register), much of the
"special" stuff can just go away, and the resulting patterns can be used by
the asm parser.

No significant change in generated code expected.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178006 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:56:22 +00:00
Ulrich Weigand
d67768db80 PowerPC: Remove LDrs pattern.
The LDrs pattern is a duplicate of LD, except that it accepts memory
addresses where the displacement is a symbolLo64.  An operand type
"memrs" is defined for just that purpose.

However, this wouldn't be necessary if the default "memrix" operand
type were to simply accept 64-bit symbolic addresses directly.
The only problem with that is that it uses "symbolLo", which is
hardcoded to 32-bit.

To fix this, this commit changes "memri" and "memrix" to use new
operand types for the memory displacement, which allow iPTR
instead of i32.  This will also make address parsing easier to
implment in the asm parser.

No change in generated code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178005 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:55:45 +00:00
Ulrich Weigand
2b0850b830 PowerPC: Remove ADDIL patterns.
The ADDI/ADDI8 patterns are currently duplicated into ADDIL/ADDI8L,
which describe the same instruction, except that they accept a
symbolLo[64] operand instead of a s16imm[64] operand.

This duplication confuses the asm parser, and it actually not really
needed, since symbolLo[64] already accepts immediate operands anyway.
So this commit removes the duplicate patterns.

No change in generated code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178004 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:55:20 +00:00
Ulrich Weigand
a01c7dbaab PowerPC: Use CCBITRC operand for ISEL patterns.
This commit changes the ISEL patterns to use a CCBITRC operand
instead of a "pred" operand.  This matches the actual instruction
text more directly, and simplifies use of ISEL with the asm parser.
In addition, this change allows some simplification of handling
the "pred" operand, as this is now only used by BCC.

No change in generated code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178003 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:54:54 +00:00
Ulrich Weigand
3b25529336 PowerPC: Simplify BLR pattern.
The BLR pattern cannot be recognized by the asm parser in its current form.
This complexity is due to an apparent attempt to enable conditional BLR
variants.  However, none of those can ever be generated by current code;
the pattern is only ever created using the default "pred" operand.

To simplify the pattern and allow it to be recognized by the parser,
this commit removes those attempts at conditional BLR support.

When we later come back to actually add real conditional BLR, this
should probably be done via a fully generic conditional branch pattern.

No change in generated code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178002 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:53:27 +00:00
Ulrich Weigand
e8680da874 PowerPC: Move some 64-bit branch patterns.
In PPCInstr64Bit.td, some branch patterns appear in a different sequence
than the corresponding 32-bit patterns in PPCInstrInfo.td.

To simplify future changes that affect both files, this commit moves
those patterns to rearrange them into a similar sequence.

No effect on generated code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178001 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:53:03 +00:00
Ulrich Weigand
5b390e4cd8 Use direct types in PowerPC instruction patterns.
This commit updates the PowerPC back-end (PPCInstrInfo.td and
PPCInstr64Bit.td) to use types instead of register classes in
instruction patterns, along the lines of Jakob Stoklund Olesen's
changes in r177835 for Sparc.
 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177890 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-25 19:05:30 +00:00
Ulrich Weigand
1492a4e518 Use direct types in PowerPC Pat patterns.
This commit updates the PowerPC back-end (PPCInstrInfo.td and
PPCInstr64Bit.td) to use types instead of register classes in
Pat patterns, along the lines of Jakob Stoklund Olesen's
changes in r177829 for Sparc.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177889 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-25 19:04:58 +00:00
Hal Finkel
526d6c451b PPC ZERO register needs a register number of 0.
In order for the new ZERO register to be used with MC, etc. we need to specify
its register number (0).

Thanks to Kai for reporting the problem!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177833 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-23 22:06:07 +00:00
Hal Finkel
3f2c047f32 Note in PPCFunctionInfo VRSAVE spills
In preparation for using the new register scavenger capability for providing
more than one register simultaneously, specifically note functions that have
spilled VRSAVE (currently, this can happen only in functions that use the
setjmp intrinsic). As with CR spilling, such functions will need to provide two
emergency spill slots to the scavenger.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177832 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-23 22:06:03 +00:00
Hal Finkel
7d35f74a5d MCize the bcl instruction in PPCAsmPrinter
I recently added a BCL instruction definition as part of implementing SjLj
support. This can also be used to MCize bcl emission in the asm printer.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177830 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-23 20:53:15 +00:00
Hal Finkel
02327fefd8 Cleanup some unused reg. scavenger parameters in PPCRegisterInfo
These spilling functions will eventually make use of the register scavenger,
however, they'll do so by taking advantage of PEI's virtual-register-based
delayed scavenging mechanism. As a result, these function parameters will not
be used, and can be removed.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177827 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-23 19:36:47 +00:00
Hal Finkel
7257fda1b3 Remove dead PPC LR spilling code
The LR register is unconditionally reserved, and its spilling and restoration
is handled by the prologue/epilogue code. As a result, it is never explicitly
spilled by the register allocator.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177823 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-23 17:14:27 +00:00
Hal Finkel
dc3beb9017 Allow the register scavenger to spill multiple registers
This patch lets the register scavenger make use of multiple spill slots in
order to guarantee that it will be able to provide multiple registers
simultaneously.

To support this, the RS's API has changed slightly: setScavengingFrameIndex /
getScavengingFrameIndex have been replaced by addScavengingFrameIndex /
isScavengingFrameIndex / getScavengingFrameIndices.

In forthcoming commits, the PowerPC backend will use this capability in order
to implement the spilling of condition registers, and some special-purpose
registers, without relying on r0 being reserved. In some cases, spilling these
registers requires two GPRs: one for addressing and one to hold the value being
transferred.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177774 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22 23:32:27 +00:00
Ulrich Weigand
86765fbe17 Remove ABI-duplicated call instruction patterns.
We currently have a duplicated set of call instruction patterns depending
on the ABI to be followed (Darwin vs. Linux).  This is a bit odd; while the
different ABIs will result in different instruction sequences, the actual
instructions themselves ought to be independent of the ABI.  And in fact it
turns out that the only nontrivial difference between the two sets of
patterns is that in the PPC64 Linux ABI, the instruction used for indirect
calls is marked to take X11 as extra input register (which is indeed used
only with that ABI to hold an incoming environment pointer for nested
functions).  However, this does not need to be hard-coded at the .td
pattern level; instead, the C++ code expanding calls can simply add that
use, just like it adds uses for argument registers anyway.

No change in generated code expected.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177735 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22 15:24:13 +00:00
Ulrich Weigand
89ec847ec7 Rename memrr ptrreg and offreg components.
Currently, the sub-operand of a memrr address that corresponds to what
hardware considers the base register is called "offreg", while the
sub-operand that corresponds to the offset is called "ptrreg".

To avoid confusion, this patch simply swaps the named of those two
sub-operands and updates all uses.  No functional change is intended.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177734 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22 14:59:13 +00:00
Ulrich Weigand
881a7154b9 Fix swapped BasePtr and Offset in pre-inc memory addresses.
PPCTargetLowering::getPreIndexedAddressParts currently provides
the base part of a memory address in the offset result, and the
offset part in the base result.  That swap is then undone again
when an MI instruction is generated (in PPCDAGToDAGISel::Select
for loads, and using .md Pat patterns for stores).

This patch reverts this double swap, to make common code and
back-end be in sync as to which part of the address is base
and which is offset.

To avoid performance regressions in certain cases, target code
now checks whether the choice of base register would be rejected
for pre-inc accesses by common code, and attempts to swap base
and offset again in such cases.  (Overall, this means that now
pre-ice accesses are generated *more* frequently than before.)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177733 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22 14:58:48 +00:00
Ulrich Weigand
0301e79a1a Tighten iaddroff ComplexPattern.
The iaddroff ComplexPattern is supposed to recognize displacement
expressions that have been processed by a SelectAddressRegImm,
which means it needs to accept TargetConstant and TargetGlobalAddress
nodes.  Currently, it erroneously also accepts some other nodes,
in particular Constant and PPCISD::Lo.

While this problem is currently latent, it would cause wrong-code
bugs with a follow-on patch I'm about to commit, so this patch
tightens the ComplexPattern.  The equivalent change is made in
PPCDAGToDAGISel::Select, where pre-inc load patterns are handled
(as opposed to store patterns, the loads are handled in C++ code
without making use of the .td ComplexPattern).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177732 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22 14:58:17 +00:00
Ulrich Weigand
cff0faa16a Remove the xaddroff ComplexPattern.
The xaddroff pattern is currently (mistakenly) used to recognize
the *base* register in pre-inc store patterns.  This patch replaces
those uses by ptr_rc_nor0 (as is elsewhere done to match the base
register of an address), and removes the now unused ComplexPattern.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177731 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22 14:57:48 +00:00
Hal Finkel
7697370adf Remove the G8RC_NOX0_and_GPRC_NOR0 PPC register class
As Jakob pointed out in his review of r177423, having a shared ZERO
register between the 32- and 64-bit register classes causes this
odd G8RC_NOX0_and_GPRC_NOR0 class to be created. As recommended,
this adds a ZERO8 register which differentiates the 32- and 64-bit
zeros.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177683 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21 23:45:03 +00:00
Hal Finkel
3ea1b064a0 Fix a register-class comparison bug in PPCCTRLoops
Thanks to Jakob for isolating the underlying problem from the
test case in r177423. The original commit had introduced
asymmetric copy operations, but these turned out to be a work-around
to the real problem (the use of == instead of hasSubClassEq in PPCCTRLoops).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177679 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21 23:23:34 +00:00
Hal Finkel
7ee74a663a Implement builtin_{setjmp/longjmp} on PPC
This implements SJLJ lowering on PPC, making the Clang functions
__builtin_{setjmp/longjmp} functional on PPC platforms. The implementation
strategy is similar to that on X86, with the exception that a branch-and-link
variant is used to get the right jump address. Credit goes to Bill Schmidt for
suggesting the use of the unconditional bcl form (instead of the regular bl
instruction) to limit return-address-cache pollution.

Benchmarking the speed at -O3 of:

static jmp_buf env_sigill;

void foo() {
                __builtin_longjmp(env_sigill,1);
}

main() {
	...

        for (int i = 0; i < c; ++i) {
                if (__builtin_setjmp(env_sigill)) {
                        goto done;
                } else {
                        foo();
                }

done:;
        }

	...
}

vs. the same code using the libc setjmp/longjmp functions on a P7 shows that
this builtin implementation is ~4x faster with Altivec enabled and ~7.25x
faster with Altivec disabled. This comparison is somewhat unfair because the
libc version must also save/restore the VSX registers which we don't yet
support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177666 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21 21:37:52 +00:00
Hal Finkel
10f7f2a222 Add support for spilling VRSAVE on PPC
Although there is only one Altivec VRSAVE register, it is a member of
a register class, and we need the ability to spill it. Because this
register is normally callee-preserved and handled by special code this
has never before been necessary. However, this capability will be required by
a forthcoming commit adding SjLj support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177654 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21 19:03:21 +00:00
Hal Finkel
e9cc0a09ae Correct PPC FRAMEADDR lowering using a pseudo-register
The old code used to lower FRAMEADDR tried to replicate the logic in the real
frame-lowering code that determines whether or not the frame pointer (r31) will
be used. When it seemed as through the frame pointer would not be used, the
stack pointer (r1) was used instead. Unfortunately, because the stack size is
not yet known, this does not work. Instead, this change introduces new
always-reserved pseudo-registers (FP and FP8) that are replaced during prologue
insertion with the real frame-pointer register (either r1 or r31).

It is important that this intrinsic always return a valid frame address because
it is used by Clang to store the frame address as part of code generation for
__builtin_setjmp.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177653 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21 19:03:19 +00:00
Ulrich Weigand
dff4d1522a Add missing mayLoad flag to LHAUX8 and LWAUX.
All pre-increment load patterns need to set the mayLoad flag (since
they don't provide a DAG pattern).

This was missing for LHAUX8 and LWAUX, which is added by this patch.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177431 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 19:53:27 +00:00
Ulrich Weigand
8353d1e0e5 Rewrite LHAU8 pattern to use standard memory operand.
As opposed to to pre-increment store patterns, the pre-increment
load patterns were already using standard memory operands, with
the sole exception of LHAU8.

As there's no real reason why LHAU8 should be different here,
this patch simply rewrites the pattern to also use a memri
operand, just like all the other patterns.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177430 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 19:52:30 +00:00
Ulrich Weigand
5882e3d828 Rewrite pre-increment store patterns to use standard memory operands.
Currently, pre-increment store patterns are written to use two separate
operands to represent address base and displacement:

  stwu $rS, $ptroff($ptrreg)

This causes problems when implementing the assembler parser, so this
commit changes the patterns to use standard (complex) memory operands
like in all other memory access instruction patterns:

  stwu $rS, $dst

To still match those instructions against the appropriate pre_store
SelectionDAG nodes, the patch uses the new feature that allows a Pat
to match multiple DAG operands against a single (complex) instruction
operand.

Approved by Hal Finkel.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177429 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 19:52:04 +00:00
Ulrich Weigand
880d82e3db Fix sub-operand size mismatch in tocentry operands.
The tocentry operand class refers to 64-bit values (it is only used in 64-bit,
where iPTR is a 64-bit type), but its sole suboperand is designated as 32-bit
type.  This causes a mismatch to be detected at compile-time with the TableGen
patch I'll check in shortly.

To fix this, this commit changes the suboperand to a 64-bit type as well.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177427 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 19:50:30 +00:00
Hal Finkel
a548afc98f Prepare to make r0 an allocatable register on PPC
Currently the PPC r0 register is unconditionally reserved. There are two reasons
for this:

 1. r0 is treated specially (as the constant 0) by certain instructions, and so
    cannot be used with those instructions as a regular register.

 2. r0 is used as a temporary register in the CR-register spilling process
    (where, under some circumstances, we require two GPRs).

This change addresses the first reason by introducing a restricted register
class (without r0) for use by those instructions that treat r0 specially. These
register classes have a new pseudo-register, ZERO, which represents the r0-as-0
use. This has the side benefit of making the existing target code simpler (and
easier to understand), and will make it clear to the register allocator that
uses of r0 as 0 don't conflict will real uses of the r0 register.

Once the CR spilling code is improved, we'll be able to allocate r0.

Adding these extra register classes, for some reason unclear to me, causes
requests to the target to copy 32-bit registers to 64-bit registers. The
resulting code seems correct (and causes no test-suite failures), and the new
test case covers this new kind of asymmetric copy.

As r0 is still reserved, no functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177423 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 18:51:05 +00:00
Hal Finkel
ec2e968b7a Cleanup PPC64 unaligned i64 load/store
Remove an accidentally-added instruction definition and add a comment in the
test case. This is in response to a post-commit review by Bill Schmidt.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177404 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 15:23:39 +00:00
Hal Finkel
54e57f8cb7 Don't reserve R31 on PPC64 unless the frame pointer is needed
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177379 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 08:09:38 +00:00
Hal Finkel
9f2518cdc6 Fix a sign-extension bug in PPCCTRLoops
Don't sign extend the immediate value from the OR instruction in
an LIS/OR pair.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177361 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-18 23:58:28 +00:00
Hal Finkel
08a215c286 Fix PPC unaligned 64-bit loads and stores
PPC64 supports unaligned loads and stores of 64-bit values, but
in order to use the r+i forms, the offset must be a multiple of 4.
Unfortunately, this cannot always be determined by examining the
immediate itself because it might be available only via a TOC entry.

In order to get around this issue, we additionally predicate the
selection of the r+i form on the alignment of the load or store
(forcing it to be at least 4 in order to select the r+i form).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177338 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-18 23:00:58 +00:00
Hal Finkel
e39b107c46 Fix 80-col. violations in PPCCTRLoops
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177296 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-18 17:40:46 +00:00
Hal Finkel
9887ec31e6 Fix large count and negative constant count handling in PPCCTRLoops
This commit fixes an assert that would occur on loops with large constant counts
(like looping for ((uint32_t) -1) iterations on PPC64). The existing code did
not handle counts that it computed to be negative (asserting instead), but
these can be created with valid inputs.

This bug was discovered by bugpoint while I was attempting to isolate a
completely different problem.

Also, in writing test cases for the negative-count problem, I discovered that
the ori/lsi handling was broken (there was a typo which caused the logic that
was supposed to detect these pairs and extract the iteration count to always
fail). This has now also been corrected (and is covered by one of the new test
cases).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177295 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-18 17:40:44 +00:00
Hal Finkel
1448d06156 Cleanup initial-value constants in PPCCTRLoops
Because the initial-value constants had not been added to the list
of instructions considered for DCE the resulting code had redundant
constant-materialization instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177294 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-18 17:40:27 +00:00
Sylvestre Ledru
53856be683 To avoid symbol clash, undefine PPC here. PPC may be predefined on some hosts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177234 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-17 12:40:42 +00:00
Hal Finkel
3249729043 Improve PPC VR (Altivec) register spilling
This change cleans up two issues with Altivec register spilling:

  1. The spilling code was inefficient (using two instructions, and add and a
     load, when just one would do)

  2. The code assumed that r0 would always be available (true for now, but this
     will change)

The new code handles VR spilling just like GPR spills but forced into r+r mode.
As a result, when any VR spills are present, we must now always allocate the
register-scavenger spill slot.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177231 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-17 04:43:44 +00:00
Hal Finkel
ce638c8248 Remove PPC avoidWriteAfterWrite callback
As a follow-up to r158719, remove PPCRegisterInfo::avoidWriteAfterWrite.
Jakob pointed out in response to r158719 that this callback is currently unused
and so this has no effect (and the speedups that I thought that I had observed
as a result of implementing this function must have been noise).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177228 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-16 22:50:51 +00:00
Hal Finkel
2d37f7b979 Enable unaligned memory access on PPC for scalar types
Unaligned access is supported on PPC for non-vector types, and is generally
more efficient than manually expanding the loads and stores.

A few of the existing test cases were using expanded unaligned loads and stores
to test other features (like load/store with update), and for these test cases,
unaligned access remains disabled.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177160 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-15 15:27:13 +00:00
Hal Finkel
044f841267 Protect PPC Altivec patterns with a predicate
In preparation for the addition of other SIMD ISA extensions (such as QPX) we
need to make sure that all Altivec patterns are properly predicated on having
Altivec support.

No functionality change intended (one test case needed to be updated b/c it
assumed that Altivec intrinsics would be supported without enabling Altivec
support).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177152 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-15 13:21:21 +00:00
Hal Finkel
0cfb42adb5 Allocate the RS spill slot for any PPC function with spills and a large stack frame
For spills into a large stack frame, the FI-elimination code uses the register
scavenger to obtain a free GPR for use with an r+r-addressed load or store.
When there are no available GPRs, the scavenger gets one by using its spill
slot. Previously, we were not always allocating that spill slot and the RS
would assert when the spill slot was needed.

I don't currently have a small test that triggered the assert, but I've
created a small regression test that verifies that the spill slot is now
added when the stack frame is sufficiently large.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177140 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-15 05:06:04 +00:00