Commit Graph

81329 Commits

Author SHA1 Message Date
Matthias Braun
a36268215f PrologEpilogInserter: Rewrite API to determine callee save regsiters.
This changes TargetFrameLowering::processFunctionBeforeCalleeSavedScan():

- Rename the function to determineCalleeSaves()
- Pass a bitset of callee saved registers by reference, thus avoiding
  the function-global PhysRegUsed bitset in MachineRegisterInfo.
- Without PhysRegUsed the implementation is fine tuned to not save
  physcial registers which are only read but never modified.

Related to rdar://21539507

Differential Revision: http://reviews.llvm.org/D10909

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242165 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 17:17:13 +00:00
Tim Northover
93398438ff AArch64: add rev64 alias for 64-bit rev instruction.
It could be useful to assembly programmers and makes the permitted variants a
little more uniform.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242164 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 17:07:29 +00:00
Krzysztof Parzyszek
14e60218b6 [Hexagon] Generate "extract" instructions more aggressively
Generate extract instructions (via intrinsics) before the DAG combiner
folds shifts into unrecognizable forms.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242163 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 17:07:24 +00:00
Hans Wennborg
5c63c6a361 ARMAsmParser: Take MCInst param by const-ref
(Broken out from http://reviews.llvm.org/D11167)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242160 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 16:39:01 +00:00
Alexandros Lamprineas
b83440104d Caused regressions: compile Release+Asserts failed on clang-native-arm-cortex-a9
Revert "-Added API for retrieving the default FPU of a CPU from TargetParser."

This reverts commit 01199ab0c6.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242147 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 14:34:06 +00:00
Tom Stellard
adb194b458 AMDGPU/SI: Add support for shrinking v_cndmask_b32_e32 instructions
Reviewers: arsenm

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11061

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242146 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 14:15:03 +00:00
Aaron Ballman
bdd9e2ac3b Silencing two MSVC warnings; 'argument' : truncation from 'unsigned int' to 'int16_t' and truncation of constant value. NFC intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242145 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 14:14:00 +00:00
Alexandros Lamprineas
01199ab0c6 -Added API for retrieving the default FPU of a CPU from TargetParser.
-Implemented as a table lookup.

Change-Id: Ibf7217f6bd2769e9c06835a5aede3d072dee6757
Phabricator: http://reviews.llvm.org/D11100

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242141 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 13:20:48 +00:00
Daniel Sanders
815d6131a4 [mips] Fix li/la differences between IAS and GAS.
Summary:
- Signed 16-bit should have priority over unsigned.
- For la, unsigned 16-bit must use ori+addu rather than directly use ori.
- Correct tests on 32-bit immediates with 64-bit predicates by
  sign-extending the immediate beforehand. For example, isInt<16>(0xffff8000)
  should be true and use addiu.

Also split li/la testing into separate files due to their size.

Reviewers: vkalintiris

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10967

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242139 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 12:24:22 +00:00
Chandler Carruth
2364d1f548 [PM/AA] Reformat GlobalsModRef so that subsequent patches I make here
don't continually introduce formatting deltas. NFC

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242129 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 08:42:39 +00:00
David Majnemer
2a27389edc [SROA] Don't de-atomic volatile loads and stores
Volatile loads and stores are made visible in global state regardless of
what memory is involved.  It is not correct to disregard the ordering
and synchronization scope because it is possible to synchronize with
memory operations performed by hardware.

This partially addresses PR23737.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242126 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 06:19:58 +00:00
Yaron Keren
6f1e023b46 Generate correct asm info for mingw and cygwin ARM targets.
http://reviews.llvm.org/D11075

Patch by Martell Malone
Reviewed by Reid Kleckner



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242123 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 05:51:05 +00:00
NAKAMURA Takumi
9743de8916 Prune trailing whitespaces and CRs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242117 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 04:03:49 +00:00
Matthias Braun
21910d8bd5 Revert "LegalizeDAG: Fix and improve FCOPYSIGN/FABS legalization"
Accidental commit, needs review first.

This reverts commit r242107.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242108 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 02:09:57 +00:00
Matthias Braun
2a46e4c020 LegalizeDAG: Fix and improve FCOPYSIGN/FABS legalization
- Factor out code to query and modify the sign bit of a floatingpoint
  value as an integer. This also works if none of the targets integer
  types is big enough to hold all bits of the floatingpoint value.

- Legalize FABS(x) as FCOPYSIGN(x, 0.0) if FCOPYSIGN is available,
  otherwise perform bit manipulation on the sign bit. The previous code
  used "x >u 0 ? x : -x" which is incorrect for x being -0.0! It also
  takes 34 instructions on ARM Cortex-M4. With this patch we only
  require 5:
    vldr d0, LCPI0_0
    vmov r2, r3, d0
    lsrs r2, r3, #31
    bfi r1, r2, #31, #1
    bx lr
  (This could be further improved if the compiler would recognize that
   r2, r3 is zero).

- Only lower FCOPYSIGN(x, y) = sign(x) ? -FABS(x) : FABS(x) if FABS is
  available otherwise perform bit manipulation on the sign bit.

- Perform the sign(x) test by masking out the sign bit and comparing
  with 0 rather than shifting the sign bit to the highest position and
  testing for "<s 0". For x86 copysignl (on 80bit values) this gets us:
    testl $32768, %eax
  rather than:
    shlq $48, %rax
    sets %al
    testb %al, %al

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242107 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 02:08:26 +00:00
Andrew Wilkins
7c492a1752 Add capability to get and set the personalitty function from the C API
Summary:
The capability was lost with D10429 where the personality function was set at function level rather than landing pad level. Now there is no way to get/set the personality function from the C API. That is a problem.

Note that the whole thing could be avoided by improving the C API testing, as started by D10725

Reviewers: chandlerc, bogner, majnemer, andrew.w.kaylor, rafael, rnk, axw

Subscribers: rafael, llvm-commits

Differential Revision: http://reviews.llvm.org/D10946

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242104 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 01:23:06 +00:00
Rafael Espindola
ec6cc055ce Add a herper function. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242100 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 01:06:16 +00:00
Alex Lorenz
dee03ee0f9 MIR Serialization: Serialize the variable sized stack objects.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242095 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 00:26:26 +00:00
Reid Kleckner
b53f724f91 Update enforceKnownAlignment after the isWeakForLinker semantic change
Previously we would refrain from attempting to increase the linkage of
available_externally globals because they were considered weak for the
linker. Now they are treated more like a declaration instead of a weak
definition.

This was causing SSE alignment faults in Chromuim, when some code
assumed it could increase the alignment of a dllimported global that it
didn't control.  http://crbug.com/509256

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242091 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 00:11:08 +00:00
Alex Lorenz
c249168837 MIR Serialization: Serialize the sub register indices.
This commit serializes the sub register indices from the register machine
operands.

Reviewers: Duncan P. N. Exon Smith


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242084 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 23:24:34 +00:00
Rafael Espindola
f2343bd953 Fix reading archive members with / in the name.
This is important for thin archives.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242082 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 23:07:05 +00:00
Bill Schmidt
045b2171c4 [PPC64LE] More improvements to VSX swap optimization
This patch allows VSX swap optimization to succeed more frequently.
Specifically, it is concerned with common code sequences that occur
when copying a scalar floating-point value to a vector register.  This
patch currently handles cases where the floating-point value is
already in a register, but does not yet handle loads (such as via an
LXSDX scalar floating-point VSX load).  That will be dealt with later.

A typical case is when a scalar value comes in as a floating-point
parameter.  The value is copied into a virtual VSFRC register, and
then a sequence of SUBREG_TO_REG and/or COPY operations will convert
it to a full vector register of the class required by the context.  If
this vector register is then used as part of a lane-permuted
computation, the original scalar value will be in the wrong lane.  We
can fix this by adding a swap operation following any widening
SUBREG_TO_REG operation.  Additional COPY operations may be needed
around the swap operation in order to keep register assignment happy,
but these are pro forma operations that will be removed by coalescing.

If a scalar value is otherwise directly referenced in a computation
(such as by one of the many XS* vector-scalar operations), we
currently disable swap optimization.  These operations are
lane-sensitive by definition.  A MentionsPartialVR flag is added for
use in each swap table entry that mentions a scalar floating-point
register without having special handling defined.

A common idiom for PPC64LE is to convert a double-precision scalar to
a vector by performing a splat operation.  This ensures that the value
can be referenced as V[0], as it would be for big endian, whereas just
converting the scalar to a vector with a SUBREG_TO_REG operation
leaves this value only in V[1].  A doubleword splat operation is one
form of an XXPERMDI instruction, which takes one doubleword from a
first operand and another doubleword from a second operand, with a
two-bit selector operand indicating which doublewords are chosen.  In
the general case, an XXPERMDI can be permitted in a lane-swapped
region provided that it is properly transformed to select the
corresponding swapped values.  This transformation is to reverse the
order of the two input operands, and to reverse and complement the
bits of the selector operand (derivation left as an exercise to the
reader ;).

A new test case that exercises the scalar-to-vector and generalized
XXPERMDI transformations is added as CodeGen/PowerPC/swaps-le-5.ll.
The patch also requires a change to CodeGen/PowerPC/swaps-le-3.ll to
use CHECK-DAG instead of CHECK for two independent instructions that
now appear in reverse order.

There are two small unrelated changes that are added with this patch.
First, the XXSLDWI instruction was incorrectly omitted from the list
of lane-sensitive instructions; this is now fixed.  Second, I observed
that the same webs were being rejected over and over again for
different reasons.  Since it's sufficient to reject a web only once, I
added a check for this to speed up the compilation time slightly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242081 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 22:58:19 +00:00
Pete Cooper
71a4b301fd Loop idiom recognizer was replacing too many uses of popcount.
When spotting that a loop can use ctpop, we were incorrectly replacing all uses of a value with a value derived from ctpop.

The bug here was exposed because we were replacing a use prior to the ctpop with the ctpop value and so we have a use before def, i.e., we changed

 %tobool.5 = icmp ne i32 %num, 0
 store i1 %tobool.5, i1* %ptr
 br i1 %tobool.5, label %for.body.lr.ph, label %for.end

to

 store i1 %1, i1* %ptr
 %0 = call i32 @llvm.ctpop.i32(i32 %num)
 %1 = icmp ne i32 %0, 0
 br i1 %1, label %for.body.lr.ph, label %for.end

Even if we inserted the ctpop so that it dominates the store here, that would still be incorrect.  The store doesn’t want the result of ctpop.

The fix is very simple, and involves replacing only the branch condition with the ctpop instead of all uses.

Reviewed by Hal Finkel.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242068 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 21:25:33 +00:00
Reid Kleckner
da9c587dad [WinEH] Emit the LSDA even if no lpads remain but outlining occurred
The outlined funclets call intrinsics which reference labels from the
LSDA. This situation can easily arise in small functions with a single
cleanup at -O0, where Clang marks a definition as nounwind, and then
WinEHPrepare "discovers" that the landingpad is dead by accident and
deletes it.

We now need to ask the LLVM IR Function for it's personality directly,
rather than going through MachineModuleInfo.

Fixes PR23892.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242063 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 20:41:46 +00:00
Benjamin Kramer
360ec4c35f [Hexagon] Move BitTracker into the llvm namespace and remove redundant qualifications
No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242062 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 20:38:16 +00:00
Rafael Espindola
168b1bebf0 Add support deterministic output in llvm-ar and make it the default.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242061 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 20:38:09 +00:00
Matt Arsenault
bae3cf3a1b AMDGPU: Minor cleanups to always inline pass
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242053 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 19:08:36 +00:00
David Majnemer
8a2d65cf4a [MC] Correctly escape .safeseh's symbol
This fixes PR24107.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242050 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 18:51:15 +00:00
Mark Heffernan
9be1720729 Enable partial and runtime loop unrolling for NVPTX.
Enable partial and runtime loop unrolling for NVPTX backend via
TTI::UnrollingPreferences with a small threshold. This partially unrolls
small loops which are often unrolled by the PTX to SASS compiler
and unrolling earlier can be beneficial.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242049 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 18:33:21 +00:00
Mark Heffernan
8a9e01d606 Enable runtime unrolling with unroll pragma metadata
Enable runtime unrolling for loops with unroll count metadata ("#pragma unroll N")
and a runtime trip count. Also, do not unroll loops with unroll full metadata if the
loop has a runtime loop count. Previously, such loops would be unrolled with a
very large threshold (pragma-unroll-threshold) if runtime unrolled happened to be
enabled resulting in a very large (and likely unwise) unroll factor.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242047 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 18:26:27 +00:00
Adrian Prantl
8f5464d3ab Service the doxygen comments in DwarfUnit and DwarfDebug.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242046 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 18:25:29 +00:00
Alex Lorenz
ad7556d177 MIR Serialization: Serialize the fixed stack objects.
This commit serializes the fixed stack objects, including fixed spill slots.
The fixed stack objects are serialized using a YAML sequence of YAML inline
mappings. Each mapping has the object's ID, type, size, offset, and alignment.
The objects that aren't spill slots also serialize the isImmutable and isAliased
flags.

The fixed stack objects are a part of the machine function's YAML mapping.

Reviewers: Duncan P. N. Exon Smith


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242045 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 18:07:26 +00:00
Reid Kleckner
c6d1cc7e16 [WinEH] Strip the \01 character from the __CxxFrameHandler3 thunk name
Add another C++ 32-bit EH table test.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242044 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 17:55:14 +00:00
Benjamin Kramer
0ed5091742 Remove macro guards for extern template instantiations.
This is a C++11 feature that both GCC and MSVC have supported as ane extension
long before C++11 was approved.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242042 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 17:21:31 +00:00
Benjamin Kramer
ed5546e50b Avoid using Loop::getSubLoopsVector.
Passes should never modify it, just use the const version. While there
reduce copying in LoopInterchange. No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242041 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 17:21:14 +00:00
James Y Knight
af8cf90e2f Fix handling of the 'n' asm constraint with invalid operands.
It had accidently accepted a symbol+offset value (and emitted
incorrect code for it, keeping only the offset part) instead of
properly reporting the constraint as invalid.

Differential Revision: http://reviews.llvm.org/D11039

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242040 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 16:36:22 +00:00
Tom Stellard
f5be357d37 AMDGPU/SI: Select mad patterns to v_mac_f32
The two-address instruction pass will convert these back to v_mad_f32
if necessary.

Differential Revision: http://reviews.llvm.org/D11060

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242038 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 15:47:57 +00:00
Logan Chien
af3e4a2f2f ARM: Fix cttz expansion on vector types.
The 64/128-bit vector types are legal if NEON instructions are
available.  However, there was no matching patterns for @llvm.cttz.*()
intrinsics and result in fatal error.

This commit fixes the problem by lowering cttz to:
a. ctpop((x & -x) - 1)
b. width - ctlz(x & -x) - 1


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242037 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 15:37:30 +00:00
Scott Douglass
f8560e5a5b [ARM] Handle commutativity when converting to tADDhirr in Thumb2
Also, run thumb_rewrite.s tests in Thumb2 now that they pass.

Differential Revision: http://reviews.llvm.org/D11132

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242036 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 15:31:48 +00:00
Scott Douglass
ffc51593c8 [ARM] Add Thumb2 ADD with SP narrowing from 3 operand to 2
Differential Revision: http://reviews.llvm.org/D11131

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242035 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 15:31:40 +00:00
Scott Douglass
f716895679 [ARM] Small refactor of tryConvertingToTwoOperandForm (nfc)
Also, add more Thumb2 ADD tests requested during review of
http://reviews.llvm.org/D11053.

Differential Revision: http://reviews.llvm.org/D11130

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242034 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 15:31:33 +00:00
Silviu Baranga
5b50110192 Cleanup after r241809 - remove uncessary call to std::sort
Summary:
The iteration order within a member of DepCands is deterministic
and therefore we don't have to sort the accesses within a member.
We also don't have to copy the indices of the pointers into a
vector, since we can iterate over the members of the class.

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11145

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242033 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 14:48:24 +00:00
Rafael Espindola
46db875af8 Remove unused variable.
Sorry I missed it in the previous commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242032 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 14:43:33 +00:00
Rafael Espindola
0b2f27eb8d Aliases don't have available_externally linkage.
Allowing that is probably a good idea, but currently we don't, so
this is dead code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242031 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 14:39:02 +00:00
Rafael Espindola
94162a044b Don't change the visibility when converting a definition to a declaration.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242030 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 14:18:22 +00:00
Aaron Ballman
b3e72a7c9d Removing several -Wunused-but-set-variable warnings; NFC intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242028 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 14:04:30 +00:00
Rafael Espindola
5572685621 Print the visibility of available_externally functions.
We were already printing it for declarations, but not available_externally.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242027 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 13:55:18 +00:00
Manuel Klimek
c376473bb4 Revert r241981 "Revert "Revert r236894 "[BasicAA] Fix zext & sext handling"""
The repros from PR23626 still fail.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242025 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 13:50:55 +00:00
Elena Demikhovsky
a0a51734cd AVX-512: Added all AVX-512 forms of Vector Convert for Float/Double/Int/Long types.
In this patch I have only encoding. Intrinsics and DAG lowering will be in the next patch.
I temporary removed the old intrinsics test (just to split this patch).
Half types are not covered here.

Differential Revision: http://reviews.llvm.org/D11134



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242023 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 13:26:20 +00:00
Jingyue Wu
8e7e3650af [LSR] don't attempt to promote ephemeral values to indvars
Summary:
This at least saves compile time. I also encountered a case where
ephemeral values affect whether other variables are promoted, causing
performance issues. It may be a bug in LSR, but I didn't manage to
reduce it yet. Anyhow, I believe it's in general not worth considering
ephemeral values in LSR.

Reviewers: atrick, hfinkel

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11115

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242011 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 03:28:53 +00:00