3446 Commits

Author SHA1 Message Date
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
Hal Finkel
3080d23fde Provide the register scavenger to processFunctionBeforeFrameFinalized
Add the current PEI register scavenger as a parameter to the
processFunctionBeforeFrameFinalized callback.

This change is necessary in order to allow the PowerPC target code to
set the register scavenger frame index after the save-area offset
adjustments performed by processFunctionBeforeFrameFinalized. Only
after these adjustments have been made is it possible to estimate
the size of the stack frame.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177108 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-14 20:33:40 +00:00
Hal Finkel
1c6c61a608 Use frame-index scavenging for PPC register spilling
Make requiresFrameIndexScavenging return true, and create virtual registers in
the spilling code instead of using the register scavenger directly. This makes
the target-level code simpler, and importantly, delays the scavenging until
after callee-saved register processing (which will be important for later
changes).

Also cleans up trackLivenessAfterRegAlloc (makes it inline in the header with
the other related functions). This makes it clear that it always returns true.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177107 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-14 20:21:47 +00:00
Hal Finkel
100a94bc93 Not all PPC functions with a frame pointer need a RS spill slot
We used to add a spill slot for the register scavenger whenever the function
has a frame pointer. This is unnecessarily conservative: We may need the spill
slot for dynamic stack allocations, and functions with dynamic stack
allocations always have a FP, but we might also have a FP for other reasons
(such as the user explicitly disabling frame-pointer elimination), and we don't
necessarily need a spill slot for those functions.

The structsinregs test needed adjustment because it disables FP elimination.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177106 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-14 19:34:32 +00:00
Hal Finkel
6bc99603c0 Add a comment about overlapping PPC frame offsets
I don't think that it is otherwise clear how the overlapping offsets
are processed into distinct spill slots. Comment that this is done
in processFunctionBeforeFrameFinalized.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177094 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-14 18:38:31 +00:00
Hal Finkel
4d53e7798c Don't reserve R2 on Darwin/PPC
Now that only the register-scavenger version of the CR spilling code remains,
we no longer need the Darwin R2 hack. Darwin can use R0 as a spare register in
any case where the System V ABI uses it (R0 is special architecturally, and so
is reserved under all common ABIs).

A few test cases needed to be updated to reflect the register-allocation changes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176868 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-12 15:18:14 +00:00