Commit Graph

106098 Commits

Author SHA1 Message Date
Chandler Carruth
3c249a5a67 [SDAG] Remove a giant pile of asserts that may have helped track down
a bug in 2010 when they were added but are adding no value today.

In fact, they are utter lies. NodeAllocator is used to allocate almost
all of these node types. I don't know what we were trying to assert
here, and the docs don't give any answer. Until we once again stumble
upon a bug needing help, let's clear the path for improvements.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213610 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-22 04:03:22 +00:00
Bill Wendling
4a913e0174 Add openmp to the list of tagged things.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213608 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-22 03:17:30 +00:00
Richard Smith
434f0e3548 Revert of r213521. This change introduced a non-hermetic test (depending on a
file not in the test/ area). Backing out now so that this test isn't part of
the 3.5 branch.

Original commit message: "TableGen: Allow AddedComplexity values to be negative
[...]"


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213596 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-22 02:32:12 +00:00
Mark Heffernan
bc7f1aba2d Rename metadata llvm.loop.vectorize.unroll to llvm.loop.vectorize.interleave.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213588 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 23:11:03 +00:00
Eli Bendersky
07efe87198 Add some tests for NVPTX lowering of cmpxchg
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213586 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 22:54:44 +00:00
Hal Finkel
9da65a8644 Match semantics of PointerMayBeCapturedBefore to its name by default
As it turns out, the capture tracker named CaptureBefore used by AA, and now
available via the PointerMayBeCapturedBefore function, would have been
more-aptly named CapturedBeforeOrAt, because it considers captures at the
instruction provided. This is not always what one wants, and it is difficult to
get the strictly-before behavior given only the current interface. This adds an
additional parameter which controls whether or not you want to include
captures at the provided instruction. The default is not to include the
instruction provided, so that 'Before' matches its name.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213582 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 21:30:22 +00:00
David Blaikie
529165298e Revert "Recommit r212203: Don't try to construct debug LexicalScopes hierarchy for functions that do not have top level debug information."
This reverts commit r212649 while I investigate/reduce/etc PR20367.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213581 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 20:45:59 +00:00
Tom Stellard
6892361eee test-release.sh: Add support for dot releases
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213580 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 20:20:08 +00:00
Saleem Abdulrasool
7ed655da8c R600: silence GCC warning
GCC believes it may be possible to not return a value from the switch:
  lib/Target/R600/SIRegisterInfo.cpp:187:1: warning: control reaches end of non-void function [-Wreturn-type]

Add an unreachable label to indicate that this is not possible and still permit
switch coverage checking.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213572 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 17:52:00 +00:00
Tom Stellard
163d8ce61f R600/SI: Refactor VOP3 instruction definitions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213571 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 17:44:29 +00:00
Tom Stellard
3ee2c33655 R600/SI: Separate encoding and operand definitions into their own classes
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213570 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 17:44:28 +00:00
Logan Chien
8c4cf40507 Replace the result usages while legalizing cmpxchg.
We should update the usages to all of the results;
otherwise, we might get assertion failure or SEGV during
the type legalization of ATOMIC_CMP_SWAP_WITH_SUCCESS
with two or more illegal types.

For example, in the following sequence, both i8 and i1
might be illegal in some target, e.g. armv5, mipsel, mips64el,

    %0 = cmpxchg i8* %ptr, i8 %desire, i8 %new monotonic monotonic
    %1 = extractvalue { i8, i1 } %0, 1

Since both i8 and i1 should be legalized, the corresponding
ATOMIC_CMP_SWAP_WITH_SUCCESS dag will be checked/replaced/updated
twice.

If we don't update the usage to *ALL* of the results in the
first round, the DAG for extractvalue might be processed earlier.
The GetPromotedInteger() will result in assertion failure,
because its operand (i.e. the success bit of cmpxchg) is not
promoted beforehand.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213569 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 17:33:44 +00:00
Tom Stellard
d7858afe79 R600/SI: Initailize encoding fields of unused VOP3 modifiers to 0
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213564 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 17:12:40 +00:00
Tom Stellard
0794af86a1 R600/SI: Initialize unused VOP3 sources to 0 instead of SIOperand.ZERO
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213563 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 17:12:37 +00:00
Duncan P. N. Exon Smith
facdfc6781 Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges."
This reverts commit r213474 (and r213475), which causes a miscompile on
a stage2 LTO build.  I'll reply on the list in a moment.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213562 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 17:06:51 +00:00
Tom Stellard
9787e8c76b R600/SI: Add instruction shrinking pass
This pass converts 64-bit instructions to 32-bit when possible.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213561 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 16:55:33 +00:00
Dan Liew
cef5388ce8 Fix Sphinx warnings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213559 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 16:39:00 +00:00
Tom Stellard
df99a7f5dc R600/SI: VOPC instructions explicitly define VCC
Therefore we don't need to add it to the implict defs list.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213558 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 16:27:24 +00:00
David Blaikie
95689f0845 Correct the ownership passing semantics of object::createBinary and make them explicit in the type system.
createBinary documented that it destroyed the parameter in error cases,
though by observation it does not. By passing the unique_ptr by value
rather than lvalue reference, callers are now explicit about passing
ownership and the function implements the documented contract. Remove
the explicit documentation, since now the behavior cannot be anything
other than what was documented, so it's redundant.

Also drops a unique_ptr::release in llvm-nm that was always run on a
null unique_ptr anyway.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213557 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 16:26:24 +00:00
David Blaikie
d8fa9295c8 Remove unnecessary use of unique_ptr::release() used to construct another unique_ptr.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213556 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 16:23:21 +00:00
David Blaikie
0c466c88d4 Remove unused variable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213554 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 16:13:24 +00:00
Tom Stellard
05388f25d7 R600/SI: Clean up some of the unused REGISTER_{LOAD,STORE} code
There are a few more cleanups to do, but I ran into some problems
with ext loads and trunc stores, when I tried to change some of the
vector loads and stores from custom to legal, so I wasn't able to
get rid of everything.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213552 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 15:45:06 +00:00
Tom Stellard
3280804237 R600/SI: Use scratch memory for large private arrays
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213551 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 15:45:01 +00:00
Tom Stellard
c912b101d2 R600/SI: Specify wavefront size for SI and CI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213550 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 15:44:58 +00:00
Tom Stellard
59b8363f8a R600/SI: Remove vaddr operand from BUFFER_LOAD_*_OFFSET instructions
This operand is never used.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213549 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 15:44:55 +00:00
Daniel Sanders
2479def756 [mips] Do not emit '.module fp=...' unless we really need to.
We now emit this value when we need to contradict the default value. This
restores support for binutils 2.24.

When a suitable binutils has been released we can resume unconditionally
emitting .module directives. This is preferable to omitting the .module
directives since the .module directives protect against, for example,
accidentally assembling FP32 code with -mfp64 and producing an unusuable object.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213548 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 15:25:24 +00:00
Robert Khasanov
aac33cfc08 [SKX] Enabling SKX target and AVX512BW, AVX512DQ, AVX512VL features.
Enabling HasAVX512{DQ,BW,VL} predicates.
Adding VK2, VK4, VK32, VK64 masked register classes.
Adding new types (v64i8, v32i16) to VR512.
Extending calling conventions for new types (v64i8, v32i16)

Patch by Zinovy Nis <zinovy.y.nis@intel.com>
Reviewed by Elena Demikhovsky <elena.demikhovsky@intel.com>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213545 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 14:54:21 +00:00
Tom Stellard
9f276b7021 docs: Update relaease documents to include the patch number in the RELEASE tags
This will make it easier to update the release scripts to support
bug-fix releases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213544 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 14:28:31 +00:00
Dan Liew
285c82122d Export LLVM_ENABLE_ASSERTIONS in LLVMConfig.cmake so clients know
if the version of LLVM they are trying to use was built with or
without assertions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213532 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 14:17:15 +00:00
Tom Stellard
b664d47cb0 R600/SI: Store constant initializer data in constant memory
This implements a solution for constant initializers suggested
by Vadim Girlin, where we store the data after the shader code
and then use the S_GETPC instruction to compute its address.

This saves use the trouble of creating a new buffer for constant data
and then having to pass the pointer to the kernel via user SGPRs or the
input buffer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213530 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 14:01:14 +00:00
Tom Stellard
b97240dba8 R600/SI: Add isCFDepth0 Predicate to SALU addc pattern
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213529 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 14:01:12 +00:00
Tom Stellard
54a2540fee R600/SI: Use VALU for i1 XOR
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213528 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 14:01:10 +00:00
Tom Stellard
ad9769a118 R600/SI: Use a custom encoding method for simm16 in SOPP branch instructions
This allows us to explicitly define the type of fixup that is needed,
so we can distinguish this from future fixup types.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213527 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 14:01:08 +00:00
Tom Stellard
efb733cbba R600/SI: Rename SOPP operands to match the encoding fields
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213526 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 14:01:05 +00:00
Daniel Sanders
6816d66d99 [mips] Add MipsOptionRecord abstraction and use it to implement .reginfo/.MIPS.options
This abstraction allows us to support the various records that can be placed in
the .MIPS.options section in the future. We currently use it to record register
usage information (the ODK_REGINFO record in our ELF64 spec).

Each .MIPS.options record should subclass MipsOptionRecord and provide an
implementation of EmitMipsOptionRecord.

Patch by Matheus Almeida and Toma Tabacu



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213522 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 13:30:55 +00:00
Tom Stellard
4950ae5960 TableGen: Allow AddedComplexity values to be negative
This is useful for cases when stand-alone patterns are preferred to the
patterns included in the instruction definitions.  Instead of requiring
that stand-alone patterns set a larger AddedComplexity value, which
can be confusing to new developers, the allows us to reduce the
complexity of the included patterns to achieve the same result.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213521 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 13:28:54 +00:00
Hal Finkel
8db585afaa Move the CapturesBefore tracker from AA into CaptureTracking
There were two generally-useful CaptureTracker classes defined in LLVM: the
simple tracker defined in CaptureTracking (and made available via the
PointerMayBeCaptured utility function), and the CapturesBefore tracker
available only inside of AA. This change moves the CapturesBefore tracker into
CaptureTracking, generalizes it slightly (by adding a ReturnCaptures
parameter), and makes it generally available via a PointerMayBeCapturedBefore
utility function.

This logic will be needed, for example, to perform noalias function parameter
attribute inference.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213519 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 13:15:48 +00:00
Aaron Ballman
6dbe7b1e31 This declaration has no definition, which is causing MSVC to emit several "no suitable definition provided for explicit template instantiation request" C4661 warnings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213517 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 13:08:08 +00:00
Aaron Ballman
bb9fd2cbd4 Fixing an MSVC conversion warning about implicitly converting the shift results to 64-bits. No functional change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213515 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 12:31:43 +00:00
Hal Finkel
43b125912e Move isIdentifiedFunctionLocal from BasicAA to AA
The ability to identify function locals will exist outside of BasicAA (for
example, logic for inferring noalias function arguments will need this), so
make this concept generally accessible without code duplication.

No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213514 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 12:27:23 +00:00
Daniel Sanders
34e658840e [mips] Try to fix the test/ExecutionEngine tests on a MIPS host.
Fix a dangerous default case that caused MipsCodeEmitter to discard pseudo
instructions it didn't recognize. It will now call llvm_unreachable() for
unrecognized pseudo's and explicitly handles PseudoReturn, PseudoReturn64,
PseudoIndirectBranch, PseudoIndirectBranch64, CFI_INSTRUCTION, IMPLICIT_DEF,
and KILL.

There may be other pseudos that need handling but this was enough for the
ExecutionEngine tests to pass on my test system.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213513 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 12:25:34 +00:00
Daniel Sanders
8ecdc6d34f [mips] Do not emit '.module [no]oddspreg' unless we really need to.
We now emit this directive when we need to contradict the default value (e.g.
-mno-odd-spreg is given) or an option changed the default value (e.g. -mfpxx
is given).

This restores support for the currently available head of binutils. However,
at this point binutils 2.24 is still not sufficient since it does not support
'.module fp=...'.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213511 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 10:45:47 +00:00
Chandler Carruth
80a15c2ff3 FileCheck-ize a test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213508 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 09:23:21 +00:00
Tim Northover
f8d927f22b CodeGen: emit IR-level f16 conversion intrinsics as fptrunc/fpext
This makes the first stage DAG for @llvm.convert.to.fp16 an fptrunc,
and correspondingly @llvm.convert.from.fp16 an fpext. The legalisation
path is now uniform, regardless of the input IR:

  fptrunc -> FP_TO_FP16 (if f16 illegal) -> libcall
  fpext -> FP16_TO_FP (if f16 illegal) -> libcall

Each target should be able to select the version that best matches its
operations and not be required to duplicate patterns for both fptrunc
and FP_TO_FP16 (for example).

As a result we can remove some redundant AArch64 patterns.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213507 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 09:13:56 +00:00
Chandler Carruth
d4cde8670c [SDAG,cleanup] Switch the DAG combiner over to use the spelling
'Worklist' consistently rather than a deeply confusing mixture of
'WorkList' and 'Worklist'.

Notably, the very 'WorkList' of the DAG combiner was exposed to target
specific DAG combines under an interface 'AddToWorklist' which was
implemented by in turn calling 'AddToWorkList' in the combiner. This has
sent me circling with the wrong case in grep one too many times.

I chose to normalize on 'Worklist' because that one won the grep-vote
for llvm/lib/... by a hundered hits or so, and it is used in places
relatively "canonical" such as InstCombine's Worklist. Let's all jsut
pick this casing, whether "correct", "good", or "bad" and be
consistent...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213506 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 08:56:44 +00:00
Chandler Carruth
0c991ec57a [SDAG] Rather than using a narrow test against the one dummy node on the
stack, filter all handle nodes from the DAG combiner worklist.

This will also handle cases where other handle nodes might be
(erroneously) added to the worklist and then cause bugs and explosions
when deleted. For example, when running the legalizer within the DAG
combiner, there are times when other handle nodes are used and can end
up here.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213505 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 08:32:31 +00:00
Andrea Di Biagio
19e39c6f12 [DAGCombiner] Improve the shuffle-vector folding logic.
Canonicalize shuffles according to rules:
 *  shuffle(A, shuffle(A, B)) -> shuffle(shuffle(A,B), A)
 *  shuffle(B, shuffle(A, B)) -> shuffle(shuffle(A,B), B)
 *  shuffle(B, shuffle(A, Undef)) -> shuffle(shuffle(A, Undef), B)

This patch helps identifying more shuffle pairs that could be combined reusing
the already existing rules in the DAGCombiner.

Added new test 'combine-vec-shuffle-5.ll' to verify that the canonicalized
shuffles are now folded into a single shuffle node by the DAGCombiner.
Added more test cases to 'combine-vec-shuffle-4.ll'.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213504 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 07:30:54 +00:00
Andrea Di Biagio
3d1975d44b [DAG] Refactor some logic. No functional change.
This patch removes function 'CommuteVectorShuffle' from X86ISelLowering.cpp
and moves its logic into SelectionDAG.cpp as method 'getCommutedVectorShuffles'.
This refactoring is in preperation of an upcoming change to the DAGCombiner.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213503 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 07:28:51 +00:00
Gerolf Hoflehner
10437f66fa Fix for regression: [Bug 20369] wrong code at -O3 on x86_64-linux-gnu in 64-bit mode
Prevents hoisting of loads above stores and sinking of stores below loads
in MergedLoadStoreMotion.cpp (rdar://15991737)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213497 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 03:02:46 +00:00
Ulrich Weigand
d4542a8cdc [PowerPC] ELFv2 aggregate passing support
This patch adds infrastructure support for passing array types
directly.  These can be used by the front-end to pass aggregate
types (coerced to an appropriate array type).  The details of the
array type being used inform the back-end about ABI-relevant
properties.  Specifically, the array element type encodes:
- whether the parameter should be passed in FPRs, VRs, or just
  GPRs/stack slots  (for float / vector / integer element types,
  respectively)
- what the alignment requirements of the parameter are when passed in
  GPRs/stack slots  (8 for float / 16 for vector / the element type
  size for integer element types) -- this corresponds to the
  "byval align" field

Using the infrastructure provided by this patch, a companion patch
to clang will enable two features:
- In the ELFv2 ABI, pass (and return) "homogeneous" floating-point
  or vector aggregates in FPRs and VRs (this is similar to the ARM
  homogeneous aggregate ABI)
- As an optimization for both ELFv1 and ELFv2 ABIs, pass aggregates
  that fit fully in registers without using the "byval" mechanism

The patch uses the functionArgumentNeedsConsecutiveRegisters callback
to encode that special treatment is required for all directly-passed
array types.  The isInConsecutiveRegs / isInConsecutiveRegsLast bits set
as a results are then used to implement the required size and alignment
rules in CalculateStackSlotSize / CalculateStackSlotAlignment etc.

As a related change, the ABI routines have to be modified to support
passing floating-point types in GPRs.  This is necessary because with
homogeneous aggregates of 4-byte float type we can now run out of FPRs
*before* we run out of the 64-byte argument save area that is shadowed
by GPRs.  Any extra floating-point arguments that no longer fit in FPRs
must now be passed in GPRs until we run out of those too.

Note that there was already code to pass floating-point arguments in
GPRs used with vararg parameters, which was done by writing the argument
out to the argument save area first and then reloading into GPRs.  The
patch re-implements this, however, in favor of code packing float arguments
directly via extension/truncation, BITCAST, and BUILD_PAIR operations.

This is required to support the ELFv2 ABI, since we cannot unconditionally
write to the argument save area (which the caller might not have allocated).
The change does, however, affect ELFv1 varags routines too; but even here
the overall effect should be advantageous: Instead of loading the argument
into the FPR, then storing the argument to the stack slot, and finally
reloading the argument from the stack slot into a GPR, the new code now
just loads the argument into the FPR, and subsequently loads the argument
into the GPR (via BITCAST).  That BITCAST might imply a save/reload from
a stack temporary (in which case we're no worse than before); but it
might be implemented more efficiently in some cases.

The final part of the patch enables up to 8 FPRs and VRs for argument
return in PPCCallingConv.td; this is required to support returning
ELFv2 homogeneous aggregates.  (Note that this doesn't affect other ABIs
since LLVM wil only look for which register to use if the parameter is
marked as "direct" return anyway.)

Reviewed by Hal Finkel.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213493 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 00:13:26 +00:00