Commit Graph

2597 Commits

Author SHA1 Message Date
Rafael Espindola 7ad97b2fe4 Add a use of shouldAssumeDSOLocal to ARM.
Now this code path knows about position independent executables.

llvm-svn: 271290
2016-05-31 15:31:55 +00:00
Ranjeet Singh 16c24f4d6e [ARM] Add backend support for load/store intrinsics.
Added support to map intrinsics
__builtin_arm_{ldc,ldcl,ldc2,ldc2l,stc,stcl,stc2,stc2l}
to their ARM instructions.

Differential Revision: http://reviews.llvm.org/D20564

llvm-svn: 271271
2016-05-31 12:39:30 +00:00
Rafael Espindola fe796dca90 Fix default reloc model on ARM.
llvm-svn: 271111
2016-05-28 10:41:15 +00:00
Renato Golin 9be88629d5 Revert "Revert "Map DynamicNoPIC to Static on non-darwin.""
This reverts commit r271096, as reverting it broke even more buildbots!

But that also means I'll break on ARM again... :(

llvm-svn: 271099
2016-05-28 04:47:13 +00:00
Renato Golin 4f22c51b09 Revert "Map DynamicNoPIC to Static on non-darwin."
This reverts commit r271052, as it broke some ARM buildbots.

llvm-svn: 271096
2016-05-28 04:24:26 +00:00
Rafael Espindola f9bda6805b Map DynamicNoPIC to Static on non-darwin.
DynamicNoPIC was only every used on darwin. This maps it to static on
ELF. It matches what is done on X86.

llvm-svn: 271052
2016-05-27 21:44:18 +00:00
Matthew Simpson 476c0afc01 [ARM, AArch64] Match additional patterns to ldN instructions
When matching an interleaved load to an ldN pattern, the interleaved access
pass checks that all users of the load are shuffles. If the load is used by an
instruction other than a shuffle, the pass gives up and an ldN is not
generated. This patch considers users of the load that are extractelement
instructions. It attempts to modify the extracts to use one of the available
shuffles rather than the load. After the transformation, the load is only used
by shuffles and will then be matched with an ldN pattern.

Differential Revision: http://reviews.llvm.org/D20250

llvm-svn: 270142
2016-05-19 21:39:00 +00:00
Ranjeet Singh dbbbef5401 [ARM] Add cdp intrinsic tests.
- Renamed intrinsics.ll to intrinsics-coprocessor.ll
  as all the tests were testing coprocessor instructions,
  also made the test checks match the full instruction.

Differential Revision: http://reviews.llvm.org/D20393

llvm-svn: 270057
2016-05-19 12:59:17 +00:00
Rafael Espindola 8c34dd8257 Delete Reloc::Default.
Having an enum member named Default is quite confusing: Is it distinct
from the others?

This patch removes that member and instead uses Optional<Reloc> in
places where we have a user input that still hasn't been maped to the
default value, which is now clear has no be one of the remaining 3
options.

llvm-svn: 269988
2016-05-18 22:04:49 +00:00
Renato Golin 4b9c0d4dcf [llc] New diagnostic handler
Without a diagnostic handler installed, llc's behaviour is to exit on the first
error that it encounters. This is very different from the behaviour of clang
and other front ends, which try to gather as many errors as possible before
exiting.

This commit adds a diagnostic handler to llc, allowing it to find and report
more than one error. The old behaviour is preserved under a flag (-exit-on-error).

Some of the tests fail with the new diagnostic handler, so they have to use the
new flag in order to run under the previous behaviour. Some of these are known
bugs, others need further investigation. Ideally, we should fix the tests and
remove the flag at some point in the future.

Reapplied after fixing the LLDB build that was broken due to the new
DiagnosticSeverity in LLVMContext.h, and fixed an UB in the new change.

Patch by Diana Picus.

llvm-svn: 269655
2016-05-16 14:28:02 +00:00
Saleem Abdulrasool 8df2f49889 ARM: support export directives for Windows
It seems that cl will emit the export directives for Windows ARM targets.  The
fact that it did this had originally been missed and this functionality was
never implemented.  This makes it possible to rely solely on the source code for
indicating what the exported interfaces are and brings us more compatibility
with cl.

llvm-svn: 269574
2016-05-14 18:58:34 +00:00
Renato Golin f4917d35c9 Revert "[llc] New diagnostic handler"
This reverts commit r269563. Even though now it passes all LLDB bots
after a local fix, there's a new buildbot it fails with tests that we
hadn't seen locally:

http://lab.llvm.org:8011/builders/clang-x86_64-linux-selfhost-modules/builds/15647

Adding those tests to the list to investigate.

llvm-svn: 269568
2016-05-14 14:37:11 +00:00
Renato Golin c001e67baf [llc] New diagnostic handler
Without a diagnostic handler installed, llc's behaviour is to exit on the first
error that it encounters. This is very different from the behaviour of clang
and other front ends, which try to gather as many errors as possible before
exiting.

This commit adds a diagnostic handler to llc, allowing it to find and report
more than one error. The old behaviour is preserved under a flag (-exit-on-error).

Some of the tests fail with the new diagnostic handler, so they have to use the
new flag in order to run under the previous behaviour. Some of these are known
bugs, others need further investigation. Ideally, we should fix the tests and
remove the flag at some point in the future.

Reapplied after fixing the LLDB build that was broken due to the new
DiagnosticSeverity in LLVMContext.h.

Patch by Diana Picus.

llvm-svn: 269563
2016-05-14 13:15:22 +00:00
Tim Northover f8b0a7af52 ARM: use callee-saved list in the order they're actually saved.
When setting the frame pointer, the offset from SP is calculated based on the
stack slot it gets allocated, but this slot is in turn based on the order of
the CSR list so that list should match the order we actually save the registers
in. Mostly it did, but in the edge-case of MachO AAPCS targets it was wrong.

llvm-svn: 269459
2016-05-13 19:16:14 +00:00
Renato Golin 1d1b82cbeb Revert "[ARM,AArch64] NFC. Add extra test cases for bswap lowering."
This reverts commit r269425, as it fails on Windows (Thumb only).

llvm-svn: 269451
2016-05-13 18:19:42 +00:00
Renato Golin e9fa3585c5 Revert "[llc] New diagnostic handler"
This reverts commit r269428, as it breaks the LLDB build. We need to
understand how to change LLDB in the same way as LLC before landing this
again.

llvm-svn: 269432
2016-05-13 16:02:44 +00:00
Renato Golin d7a64a5b23 [llc] New diagnostic handler
Without a diagnostic handler installed, llc's behaviour is to exit on the first
error that it encounters. This is very different from the behaviour of clang
and other front ends, which try to gather as many errors as possible before
exiting.

This commit adds a diagnostic handler to llc, allowing it to find and report
more than one error. The old behaviour is preserved under a flag (-exit-on-error).

Some of the tests fail with the new diagnostic handler, so they have to use the
new flag in order to run under the previous behaviour. Some of these are known
bugs, others need further investigation. Ideally, we should fix the tests and
remove the flag at some point in the future.

Patch by Diana Picus.

llvm-svn: 269428
2016-05-13 15:37:46 +00:00
Renato Golin 8793c521bc [ARM,AArch64] NFC. Add extra test cases for bswap lowering.
These tests were sitting in Phab for many months. They're good tests and should be in.

Patch by Charlie Turner.

llvm-svn: 269425
2016-05-13 15:10:24 +00:00
Renato Golin d5491ab1f9 [ARM] Fixup tests to take into account mov translation. NFC.
Alter instances in the test-suite that use immediates that can be represented
in the immediate field of a MOV. The reason for doing this is that when the
LDR rt,=imm transformation to MOV rt, imm the existing tests do not need to
be modified.

Required by the patch that fixes PR25722.

Patch by Peter Smith.

llvm-svn: 269353
2016-05-12 21:22:37 +00:00
Tim Northover b5ece527a1 ARM: stop emitting blx instructions for most calls on MachO.
I'm really not sure why we were in the first place, it's the linker's job to
convert between BL/BLX as necessary. Even worse, using BLX left Thumb calls
that could be locally resolved completely unencodable since all offsets to BLX
are multiples of 4.

rdar://26182344

llvm-svn: 269101
2016-05-10 19:17:47 +00:00
Weiming Zhao 5b5501e817 [ARM] Fix Scavenger assert due to underestimated stack size
(re-apply r268810 as it exposed an uninitialized variable in ARM MFI.
 Patch 268868 should fix that.)

Summary:
Currently, when checking if a stack is "BigStack" or not, it doesn't count into spills and arguments. Therefore, LLVM won't reserve spill slot for this actually "BigStack". This may cause scavenger failure.

Reviewers: rengolin

Subscribers: vitalybuka, aemerson, rengolin, tberghammer, danalbert, srhines, llvm-commits

Differential Revision: http://reviews.llvm.org/D19896

llvm-svn: 268869
2016-05-08 05:11:54 +00:00
Vitaly Buka e81d96be6f Revert r268810 becase it brakes msan bot.
16802==WARNING: MemorySanitizer: use-of-uninitialized-value
    lib/Target/ARM/ARMFrameLowering.cpp:1632

llvm-svn: 268833
2016-05-07 01:54:00 +00:00
Weiming Zhao 74f12d31c1 [ARM] Fix Scavenger assert due to underestimated stack size
(this is resubmit of r268529 with minor refactoring. r268529 was reverted
 at r268536 due a memory sanitizer failure.  I have not been able to
 reproduce that failure and I checked all the variable used in my change
 but I could not spot an issue. I did some refactoring and see if it will
 give a clearer hint)

Summary:
Currently, when checking if a stack is "BigStack" or not, it doesn't count into spills and arguments. Therefore, LLVM won't reserve spill slot for this actually "BigStack". This may cause scavenger failure.

Reviewers: rengolin

Subscribers: vitalybuka, aemerson, rengolin, tberghammer, danalbert, srhines, llvm-commits

Differential Revision: http://reviews.llvm.org/D19896

llvm-svn: 268810
2016-05-06 22:20:13 +00:00
Ahmed Bougacha 16547c4e31 [CodeGen] Round [SU]INT_TO_FP result when promoting from f16.
If we don't, values that aren't precisely representable in f16 could
be used as-is in a promoted f32 operation, which would produce
incorrect results.

AArch64 had the correct behavior; add a focused test.

Fixes http://llvm.org/PR26871

llvm-svn: 268700
2016-05-06 00:58:00 +00:00
Tim Northover df43264cf7 ARM: don't attempt to merge litpools referencing different PC-anchors.
Given something like:

    ldr r0, .LCPI0_0 (== pc-rel var)
    add r0, pc

    ldr r1, .LCPI0_1 (== pc-rel var)
    add r1, pc

we cannot combine the 2 ldr instructions and litpools because they get added to
a different pc to form the correct address. I think the original logic came
from a time when we fused the LDRpci/PICADD instructions into one
pseudo-instruction so the PC was always immediately at-hand. That's no longer
the case.

Should fix general-dynamic TLS access on Linux, and quite possibly other -fPIC
code that relies on litpools (e.g. v6m and -Oz compilations) though trivial
tweaks of the .ll test didn't provoke anything.

llvm-svn: 268662
2016-05-05 18:38:53 +00:00
Vitaly Buka 6b5c89262a Revert r268529 because it caused use-of-uninitialized-value
Summary: This reverts commit d88cc0862bf7da64850b89e9bb5ea9f95e7f1184.

#0 0xfed467 in llvm::ARMFrameLowering::determineCalleeSaves(llvm::MachineFunction&, llvm::BitVector&, llvm::RegScavenger*) const /mnt/b/sanitizer-buildbot2/sanitizer-x86_64-linux-bootstrap/build/llvm/lib/Target/ARM/ARMFrameLowering.cpp:1625:52
#1 0x330d4cc in (anonymous namespace)::PEI::runOnMachineFunction(llvm::MachineFunction&) /mnt/b/sanitizer-buildbot2/sanitizer-x86_64-linux-bootstrap/build/llvm/lib/CodeGen/PrologEpilogInserter.cpp:186:3
#2 0x3193e12 in llvm::MachineFunctionPass::runOnFunction(llvm::Function&) /mnt/b/sanitizer-buildbot2/sanitizer-x86_64-linux-bootstrap/build/llvm/lib/CodeGen/MachineFunctionPass.cpp:60:13
#3 0x396237d in llvm::FPPassManager::runOnFunction(llvm::Function&) /mnt/b/sanitizer-buildbot2/sanitizer-x86_64-linux-bootstrap/build/llvm/lib/IR/LegacyPassManager.cpp:1526:23
#4 0x3962a23 in llvm::FPPassManager::runOnModule(llvm::Module&) /mnt/b/sanitizer-buildbot2/sanitizer-x86_64-linux-bootstrap/build/llvm/lib/IR/LegacyPassManager.cpp:1547:16
#5 0x3963d52 in runOnModule /mnt/b/sanitizer-buildbot2/sanitizer-x86_64-linux-bootstrap/build/llvm/lib/IR/LegacyPassManager.cpp:1603:23
#6 0x3963d52 in llvm::legacy::PassManagerImpl::run(llvm::Module&) /mnt/b/sanitizer-buildbot2/sanitizer-x86_64-linux-bootstrap/build/llvm/lib/IR/LegacyPassManager.cpp:1706
#7 0x6bb910 in compileModule(char**, llvm::LLVMContext&) /mnt/b/sanitizer-buildbot2/sanitizer-x86_64-linux-bootstrap/build/llvm/tools/llc/llc.cpp:412:5
#8 0x6b3c25 in main /mnt/b/sanitizer-buildbot2/sanitizer-x86_64-linux-bootstrap/build/llvm/tools/llc/llc.cpp:218:22
#9 0x7fd4a7d37ec4 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21ec4)
#10 0x625c93 in _start (/mnt/b/sanitizer-buildbot2/sanitizer-x86_64-linux-bootstrap/build/llvm_build_msan/bin/llc+0x625c93)

Reviewers:

Subscribers:

llvm-svn: 268536
2016-05-04 19:44:11 +00:00
Weiming Zhao 2373f769ce [ARM] Fix Scavenger assert due to underestimated stack size
Summary:
Currently, when checking if a stack is "BigStack" or not, it doesn't count into spills and arguments. Therefore, LLVM won't reserve spill slot for this actually "BigStack". This may cause scavenger failure.

Reviewers: rengolin

Subscribers: aemerson, rengolin, tberghammer, danalbert, srhines, llvm-commits

Differential Revision: http://reviews.llvm.org/D19896

llvm-svn: 268529
2016-05-04 18:19:33 +00:00
Ahmed Bougacha b4af107239 [ARM] Set correct successors in CMPXCHG pseudo expansion.
transferSuccessors() would LoadCmpBB a successor of DoneBB, whereas
it should be a successor of the original MBB.

The testcase changes are caused by Thumb2SizeReduction, which
was previously confused by the broken CFG.

Follow-up to r266679.

Unfortunately, it's tricky to catch this in the verifier.

llvm-svn: 267778
2016-04-27 20:32:54 +00:00
Craig Topper d8d6be4f99 [ARM] Expand vector ctlz_zero_undef so it becomes ctlz.
The default is Legal, which results in 'Cannot select' errors.

llvm-svn: 267521
2016-04-26 05:04:37 +00:00
Craig Topper edb4a6ba98 [ARM] Expand v1i64 and v2i64 ctlz.
The default is legal, which results in 'Cannot select' errors.

llvm-svn: 267520
2016-04-26 05:04:33 +00:00
Richard Trieu d7f31a31d1 Pass the test file in through stdin instead of by filename.
When passed in via filename, this test will fail if the path to the test
has the strings "f1" and "f2" in somewhere.  Pass the file through stdin
to prevent test failures due to coincidences in path names.

llvm-svn: 267517
2016-04-26 03:43:49 +00:00
Tim Northover 5c3140f745 ARM: put extern __thread stubs in a special section.
The linker needs to know that the symbols are thread-local to do its job
properly.

llvm-svn: 267473
2016-04-25 21:12:04 +00:00
Silviu Baranga 82d04260b7 [ARM] Add support for the X asm constraint
Summary:
This patch adds support for the X asm constraint.

To do this, we lower the constraint to either a "w" or "r" constraint
depending on the operand type (both constraints are supported on ARM).

Fixes PR26493

Reviewers: t.p.northover, echristo, rengolin

Subscribers: joker.eph, jgreenhalgh, aemerson, rengolin, llvm-commits

Differential Revision: http://reviews.llvm.org/D19061

llvm-svn: 267411
2016-04-25 14:29:18 +00:00
Saleem Abdulrasool 9611518646 ARM: fix __chkstk Frame Setup on WoA
This corrects the MI annotations for the stack adjustment following the __chkstk
invocation.  We were marking the original SP usage as a Def rather than Kill.
The (new) assigned value is the definition, the original reference is killed.

Adjust the ISelLowering to mark Kills and FrameSetup as well.

This partially resolves PR27480.

llvm-svn: 267361
2016-04-24 20:12:48 +00:00
NAKAMURA Takumi 4aec5fda93 Fix llvm/test/CodeGen/ARM/Windows/dbzchk.ll not to check mixed output, take #2.
llvm-svn: 267242
2016-04-22 22:51:48 +00:00
Peter Collingbourne 265ebd7d70 CodeGen: Use PLT relocations for relative references to unnamed_addr functions.
The relative vtable ABI (PR26723) needs PLT relocations to refer to virtual
functions defined in other DSOs. The unnamed_addr attribute means that the
function's address is not significant, so we're allowed to substitute it
with the address of a PLT entry.

Also includes a bonus feature: addends for COFF image-relative references.

Differential Revision: http://reviews.llvm.org/D17938

llvm-svn: 267211
2016-04-22 20:40:10 +00:00
Saleem Abdulrasool 8237008897 test: split test into two runs
Rather than checking both stdout and stderr simultaneously, split it into two
tests.  This apparently breaks on Windows where MSVCRT does not buffer output
correctly.  NFC.

Thanks to chapuni for bringing the issue to my attention!

llvm-svn: 267179
2016-04-22 18:06:51 +00:00
Saleem Abdulrasool 12b87facf4 ARM: fix test for Windows division
This was meant to be part of SVN r267080.  cbz cannot use a high register, which
would be silently truncated.  This has now been fixed.

llvm-svn: 267092
2016-04-22 01:03:38 +00:00
Saleem Abdulrasool a028853540 ARM: restrict register class for WIN__DBZCHK
WIN__DBZCHK will insert a CBZ instruction into the stream.  This instruction
reserves 3 bits for the condition register (rn).  As such, we must ensure that
we restrict the register to a low register.  Use the tGPR class instead of GPR
to ensure that this is properly constrained.  In debug builds, we would attempt
to use lr as a condition register which would silently get truncated with no
hint that the register selection was incorrect.

llvm-svn: 267080
2016-04-21 23:53:19 +00:00
Mandeep Singh Grang 029a0567fa [LLVM] Remove unwanted --check-prefix=CHECK from unit tests. NFC.
Summary: Removed unwanted --check-prefix=CHECK from numerous unit tests.

Reviewers: t.p.northover, dblaikie, uweigand, MatzeB, tstellarAMD, mcrosier

Subscribers: mcrosier, dsanders

Differential Revision: http://reviews.llvm.org/D19279

llvm-svn: 266834
2016-04-19 23:51:52 +00:00
Tim Northover 1ee27c74cb ARM: fix assertion failure on -O0 cmpxchg.
Because lowering of CMP_SWAP_64 occurs during type legalization, there can be
i64 types produced by more than just a BUILD_PAIR or similar. My initial tests
used just incoming function args.

llvm-svn: 266828
2016-04-19 22:25:02 +00:00
Marcin Koscielnicki 3fdc257d6a [AArch64] [ARM] Make a target-independent llvm.thread.pointer intrinsic.
Both AArch64 and ARM support llvm.<arch>.thread.pointer intrinsics that
just return the thread pointer.  I have a pending patch that does the same
for SystemZ (D19054), and there are many more targets that could benefit
from one.

This patch merges the ARM and AArch64 intrinsics into a single target
independent one that will also be used by subsequent targets.

Differential Revision: http://reviews.llvm.org/D19098

llvm-svn: 266818
2016-04-19 20:51:05 +00:00
Tim Shen e885d5e4d3 [SSP, 2/2] Create llvm.stackguard() intrinsic and lower it to LOAD_STACK_GUARD
With this change, ideally IR pass can always generate llvm.stackguard
call to get the stack guard; but for now there are still IR form stack
guard customizations around (see getIRStackGuard()). Future SSP
customization should go through LOAD_STACK_GUARD.

There is a behavior change: stack guard values are not CSEed anymore,
since we should never reuse the value in case that it has been spilled (and
corrupted). See ssp-guard-spill.ll. This also cause the change of stack
size and codegen in X86 and AArch64 test cases.

Ideally we'd like to know if the guard created in llvm.stackprotector() gets
spilled or not. If the value is spilled, discard the value and reload
stack guard; otherwise reuse the value. This can be done by teaching
register allocator to know how to rematerialize LOAD_STACK_GUARD and
force a rematerialization (which seems hard), or check for spilling in
expandPostRAPseudo. It only makes sense when the stack guard is a global
variable, which requires more instructions to load. Anyway, this seems to go out
of the scope of the current patch.

llvm-svn: 266806
2016-04-19 19:40:37 +00:00
Tim Northover b629c77692 ARM: use a pseudo-instruction for cmpxchg at -O0.
The fast register-allocator cannot cope with inter-block dependencies without
spilling. This is fine for ldrex/strex loops coming from atomicrmw instructions
where any value produced within a block is dead by the end, but not for
cmpxchg. So we lower a cmpxchg at -O0 via a pseudo-inst that gets expanded
after regalloc.

Fortunately this is at -O0 so we don't have to care about performance. This
simplifies the various axes of expansion considerably: we assume a strong
seq_cst operation and ensure ordering via the always-present DMB instructions
rather than v8 acquire/release instructions.

Should fix the 32-bit part of PR25526.

llvm-svn: 266679
2016-04-18 21:48:55 +00:00
Adrian Prantl 75819aedf6 [PR27284] Reverse the ownership between DICompileUnit and DISubprogram.
Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICompositeType. DIScopes
point to the DICompileUnit to facilitate type uniquing.

Distinct DISubprograms (with isDefinition: true) are not part of the type
hierarchy and cannot be uniqued. This change removes the subprograms
list from DICompileUnit and instead adds a pointer to the owning compile
unit to distinct DISubprograms. This would make it easy for ThinLTO to
strip unneeded DISubprograms and their transitively referenced debug info.

Motivation
----------

Materializing DISubprograms is currently the most expensive operation when
doing a ThinLTO build of clang.

We want the DISubprogram to be stored in a separate Bitcode block (or the
same block as the function body) so we can avoid having to expensively
deserialize all DISubprograms together with the global metadata. If a
function has been inlined into another subprogram we need to store a
reference the block containing the inlined subprogram.

Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script
that updates LLVM IR testcases to the new format.

http://reviews.llvm.org/D19034
<rdar://problem/25256815>

llvm-svn: 266446
2016-04-15 15:57:41 +00:00
David Majnemer 0f26b0aeb4 [CodeGen] Teach LLVM how to lower @llvm.{min,max}num to {MIN,MAX}NAN
The behavior of {MIN,MAX}NAN differs from that of {MIN,MAX}NUM when only
one of the inputs is NaN: -NUM will return the non-NaN argument while
-NAN would return NaN.

It is desirable to lower to @llvm.{min,max}num to -NAN if they don't
have a native instruction for -NUM.  Notably, ARMv7 NEON's vmin has the
-NAN semantics.

N.B.  Of course, it is only safe to do this if the intrinsic call is
marked nnan.

llvm-svn: 266279
2016-04-14 07:13:24 +00:00
Tim Northover 5c02f9ad28 ARM: override cost function to re-enable ConstantHoisting (& fix it).
At some point, ARM stopped getting any benefit from ConstantHoisting because
the pass called a different variant of getIntImmCost. Reimplementing the
correct variant revealed some problems, however:

  + ConstantHoisting was modifying switch statements. This is simply invalid,
    the cases must remain integer constants no matter the notional cost.
  + ConstantHoisting was mangling alloca instructions in the entry block. These
    should be handled by FrameLowering, so constants actually have a cost of 0.
    Worse, the resulting bitcasts meant they became dynamic allocas.

rdar://25707382

llvm-svn: 266260
2016-04-13 23:08:27 +00:00
Matthias Braun 707e02c273 ARM: Use a callee save register for the swiftself parameter.
It is very likely that the swiftself parameter is alive throughout most
functions function so putting it into a callee save register should
avoid spills for the callers with only a minimum amount of extra spills
in the callees.

Currently the generated code is correct but unnecessarily spills and
reloads arguments passed in callee save registers, I will address this
in upcoming patches.

This also adds a missing check that for tail calls the preserved value
of the caller must be the same as the callees parameter.

Differential Revision: http://reviews.llvm.org/D18901

llvm-svn: 266253
2016-04-13 21:43:25 +00:00
Wei Mi 9a16d655c7 Recommit r265547, and r265610,r265639,r265657 on top of it, plus
two fixes with one about error verify-regalloc reported, and
another about live range update of phi after rematerialization.

r265547:
Replace analyzeSiblingValues with new algorithm to fix its compile
time issue. The patch is to solve PR17409 and its duplicates.

analyzeSiblingValues is a N x N complexity algorithm where N is
the number of siblings generated by reg splitting. Although it
causes siginificant compile time issue when N is large, it is also
important for performance since it removes redundent spills and
enables rematerialization.

To solve the compile time issue, the patch removes analyzeSiblingValues
and replaces it with lower cost alternatives containing two parts. The
first part creates a new spill hoisting method in postOptimization of
register allocation. It does spill hoisting at once after all the spills
are generated instead of inside every instance of selectOrSplit. The
second part queries the define expr of the original register for
rematerializaiton and keep it always available during register allocation
even if it is already dead. It deletes those dead instructions only in
postOptimization. With the two parts in the patch, it can remove
analyzeSiblingValues without sacrificing performance.

Patches on top of r265547:
r265610 "Fix the compare-clang diff error introduced by r265547."
r265639 "Fix the sanitizer bootstrap error in r265547."
r265657 "InlineSpiller.cpp: Escap \@ in r265547. [-Wdocumentation]"

Differential Revision: http://reviews.llvm.org/D15302
Differential Revision: http://reviews.llvm.org/D18934
Differential Revision: http://reviews.llvm.org/D18935
Differential Revision: http://reviews.llvm.org/D18936

llvm-svn: 266162
2016-04-13 03:08:27 +00:00
Justin Bogner 263f314ba7 CodeGen: Clear the MFI's save and restore point after PrologEpilogInserter
This state is no longer useful and not guaranteed to be valid in later
codegen passes. For example, see the added test, which would print a
savepoint of %bb.-1 without this change, and crashes with a
use-after-free error under ASan if you apply the recycling allocator
patch from llvm.org/PR26808.

llvm-svn: 266150
2016-04-12 23:21:53 +00:00
Tim Northover a6dea06fe3 ARM: use r7 as the frame-pointer on all MachO targets.
This is better for a few reasons:
  + It matches the other tooling for iOS.
  + It matches EABI in more cases (i.e. Thumb-mode, and in practice we don't
    use ARM mode).
  + It leads to infinitesimally smaller code (0.2%, yay!).

rdar://25369506

llvm-svn: 266003
2016-04-11 22:27:40 +00:00
Manman Ren 5751814eda Swift Calling Convention: swifterror target support.
Differential Revision: http://reviews.llvm.org/D18716

llvm-svn: 265997
2016-04-11 21:08:06 +00:00
Adrian Prantl b01a4d48ac More upgrading of old- and very-old-style debug info in testcases.
llvm-svn: 265953
2016-04-11 15:53:44 +00:00
James Y Knight fec5c64b63 Add trailing colons to labels in a test.
This will avoid matching on the FILENAME if it happened to contain, say,
"f4" anywhere in the file path.

llvm-svn: 265837
2016-04-08 19:49:03 +00:00
Colin LeMahieu efe3732883 Revert r265817
lld tests need to be addressed.

llvm-svn: 265822
2016-04-08 18:15:37 +00:00
Colin LeMahieu 4a1975ba8e [llvm-objdump] Printing hex instead of dec by default
Differential Revision: http://reviews.llvm.org/D18770

llvm-svn: 265817
2016-04-08 17:55:03 +00:00
Sam Parker 2d5126cdf5 [ARM] Enable SMLAW[B|T] and SMLUW[B|T] instruction selection
Added ISelDAGToDAG functions to enable selection of the smlawb, smlawt,
smulwb and smulwt instructions for the ARM backend. Also updated the smul
CodeGen test and removed the smulw one.

Differential Revision: http://reviews.llvm.org/D18892

llvm-svn: 265793
2016-04-08 16:02:53 +00:00
Manman Ren 802cd6f9d7 Swift Calling Convention: swiftcc for ARM.
Differential Revision: http://reviews.llvm.org/D18769

llvm-svn: 265482
2016-04-05 22:44:44 +00:00
Chuang-Yu Cheng d3fb38cae5 Don't delete empty preheaders in CodeGenPrepare if it would create a critical edge
Presently, CodeGenPrepare deletes all nearly empty (only phi and branch)
basic blocks. This pass can delete loop preheaders which frequently creates
critical edges. A preheader can be a convenient place to spill registers to
the stack. If the entrance to a loop body is a critical edge, then spills
may occur in the loop body rather than immediately before it. This patch
protects loop preheaders from deletion in CodeGenPrepare even if they are
nearly empty.

Since the patch alters the CFG, it affects a large number of test cases.
In most cases, the changes are merely cosmetic (basic blocks have different
names or instruction orders change slightly). I am somewhat concerned about
the test/CodeGen/Mips/brdelayslot.ll test case. If the loop preheader is not
deleted, then the MIPS backend does not take advantage of a branch delay
slot. Consequently, I would like some close review by a MIPS expert.

The patch also partially subsumes D16893 from George Burgess IV. George
correctly notes that CodeGenPrepare does not actually preserve the dominator
tree. I think the dominator tree was usually not valid when CodeGenPrepare
ran, but I am using LoopInfo to mark preheaders, so the dominator tree is
now always valid before CodeGenPrepare.

Author: Tom Jablin (tjablin)
Reviewers: hfinkel george.burgess.iv vkalintiris dsanders kbarton cycheng

http://reviews.llvm.org/D16984

llvm-svn: 265397
2016-04-05 14:06:20 +00:00
Matthias Braun 870c34f0cf ARM, AArch64, X86: Check preserved registers for tail calls.
We can only perform a tail call to a callee that preserves all the
registers that the caller needs to preserve.

This situation happens with calling conventions like preserver_mostcc or
cxx_fast_tls. It was explicitely handled for fast_tls and failing for
preserve_most. This patch generalizes the check to any calling
convention.

Related to rdar://24207743

Differential Revision: http://reviews.llvm.org/D18680

llvm-svn: 265329
2016-04-04 18:56:13 +00:00
Adrian Prantl cf0961f5ea Add missing emissionKind flags to the DICompileUnits of several old testcases.
llvm-svn: 265192
2016-04-01 22:18:43 +00:00
Adrian Prantl b8089516a5 testcase gardening: update the emissionKind enum to the new syntax. (NFC)
llvm-svn: 265081
2016-04-01 00:16:49 +00:00
Adrian Prantl b939a25707 Move the DebugEmissionKind enum from DIBuilder into DICompileUnit.
This mostly cosmetic patch moves the DebugEmissionKind enum from DIBuilder
into DICompileUnit. DIBuilder is not the right place for this enum to live
in — a metadata consumer should not have to include DIBuilder.h.
I also added a Verifier check that checks that the emission kind of a
DICompileUnit is actually legal.

http://reviews.llvm.org/D18612
<rdar://problem/25427165>

llvm-svn: 265077
2016-03-31 23:56:58 +00:00
Benjamin Kramer 569efd2cfd [ARM] Expand v1i64 and v2i64 ctpop.
The default is legal, which results in 'Cannot select' errors. This is
triggered during selfhost due to a recent cost model change.

llvm-svn: 265040
2016-03-31 19:42:04 +00:00
Manman Ren f46262e0b7 Swift Calling Convention: add swiftself attribute.
Differential Revision: http://reviews.llvm.org/D17866

llvm-svn: 264754
2016-03-29 17:37:21 +00:00
Kyle Butt 5e241b11ed [Codegen] Decrease minimum jump table density.
Minimum density for both optsize and non optsize are now options
-sparse-jump-table-density (default 10) for non optsize functions
-dense-jump-table-density (default 40) for optsize functions, which
matches the current default. This improves several benchmarks at google
at the cost of a small codesize increase. For code compiled with -Os,
the old behavior continues

llvm-svn: 264689
2016-03-29 00:23:41 +00:00
Sanjay Patel 1f867c6f9c fix checks: *_DAG -> *-DAG
llvm-svn: 264676
2016-03-28 22:11:06 +00:00
Saleem Abdulrasool 750a90df6a ARM: maintain BB ordering when expanding WIN__DBZCHK
It is possible to have a fallthrough MBB prior to MBB placement.  The original
addition of the BB would result in reordering the BB as not preceding the
successor.  Because of the fallthrough nature of the BB, we could end up
executing incorrect code or even a constant pool island!  Insert the spliced BB
into the same location to avoid that.

Thanks to Tim Northover for invaluable hints and Fiora for the discussion on
what may have been occurring!

llvm-svn: 264454
2016-03-25 19:48:06 +00:00
Saleem Abdulrasool 0dab98d926 ARM: fix optimised division on WoA
We did not have an explicit branch to the continuation BB.  When the check was
hoisted, this could permit control follow to fall through into the division
trap.  Add the explicit branch to the continuation basic block to ensure that
code execution is correct.

llvm-svn: 264370
2016-03-25 00:34:11 +00:00
Pirama Arumuga Nainar dc45aef2d8 Remove unsafe AssertZext after promoting result of FP_TO_FP16
Summary:
Some target lowerings of FP_TO_FP16, for instance ARM's vcvtb.f16.f32
instruction, do not guarantee that the top 16 bits are zeroed out.
Remove the unsafe AssertZext and add tests to exercise this.

Reviewers: jmolloy, sbaranga, kristof.beyls, aadg

Subscribers: llvm-commits, srhines, aemerson

Differential Revision: http://reviews.llvm.org/D18426

llvm-svn: 264285
2016-03-24 14:06:03 +00:00
Tim Northover b49a8a9dbb CodeGen: check return types match when emitting tail call to builtin.
We were just completely ignoring the types when determining whether we could
safely emit a libcall as a tail call. This is clearly wrong.

Theoretically, we could dig deeper looking for incidental matches (much like
the generic code in Analysis.cpp does), but it's probably not worth it for the
few libcalls that exist.

llvm-svn: 264084
2016-03-22 19:14:38 +00:00
Peter Collingbourne 86b9fbe980 ARM: Better codegen for 64-bit compares.
This introduces a custom lowering for ISD::SETCCE (introduced in r253572)
that allows us to emit a short code sequence for 64-bit compares.

Before:

	push	{r7, lr}
	cmp	r0, r2
	mov.w	r0, #0
	mov.w	r12, #0
	it	hs
	movhs	r0, #1
	cmp	r1, r3
	it	ge
	movge.w	r12, #1
	it	eq
	moveq	r12, r0
	cmp.w	r12, #0
	bne	.LBB1_2
@ BB#1:                                 @ %bb1
	bl	f
	pop	{r7, pc}
.LBB1_2:                                @ %bb2
	bl	g
	pop	{r7, pc}

After:

	push	{r7, lr}
	subs	r0, r0, r2
	sbcs.w	r0, r1, r3
	bge	.LBB1_2
@ BB#1:                                 @ %bb1
	bl	f
	pop	{r7, pc}
.LBB1_2:                                @ %bb2
	bl	g
	pop	{r7, pc}

Saves around 80KB in Chromium's libchrome.so.

Some notes on this patch:

- I don't much like the ARMISD::BRCOND and ARMISD::CMOV combines I
  introduced (nothing else needs them). However, they are necessary in
  order to avoid poor codegen, and they seem similar to existing combines
  in other backends (e.g. X86 combines (brcond (cmp (setcc Compare))) to
  (brcond Compare)).

- No support for Thumb-1. This is in principle possible, but we'd need
  to implement ARMISD::SUBE for Thumb-1.

Differential Revision: http://reviews.llvm.org/D15256

llvm-svn: 263962
2016-03-21 18:00:02 +00:00
Renato Golin 2b6b7ffd6c [ARM] Add Cortex-A32 support
Adding Cortex-A32 as an available target in the ARM backend.

Patch by Sam Parker.

llvm-svn: 263956
2016-03-21 17:29:01 +00:00
Silviu Baranga 46030585b3 [DAGCombine] Catch the case where extract_vector_elt can cause an any_ext while processing AND SDNodes
Summary:
extract_vector_elt can cause an implicit any_ext if the types don't
match. When processing the following pattern:

  (and (extract_vector_elt (load ([non_ext|any_ext|zero_ext] V))), c)

DAGCombine was ignoring the possible extend, and sometimes removing
the AND even though it was required to maintain some of the bits
in the result to 0, resulting in a miscompile.

This change fixes the issue by limiting the transformation only to
cases where the extract_vector_elt doesn't perform the implicit
extend.

Reviewers: t.p.northover, jmolloy

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18247

llvm-svn: 263935
2016-03-21 11:43:46 +00:00
Manman Ren a3a019cf90 [CXX_FAST_TLS] Fix issues in ARM.
We need to be careful on which registers can be explicitly handled
via copies. Prologue, Epilogue use physical registers and if one belongs
to the set of CSRsViaCopy, it will no longer be CSRed, since PEI overwrites
it after the explicit copies.

llvm-svn: 263857
2016-03-18 23:44:37 +00:00
Manman Ren 4865d89653 [CXX_FAST_TLS] Disable tail call when calling conventions are mismatched.
Since CXX_FAST_TLS has a bigger set of CSRs, we don't tail call when caller
and callee have mismatched calling conventions.

llvm-svn: 263856
2016-03-18 23:41:51 +00:00
Manman Ren 2828c57b6f [CXX_FAST_TLS] fix issues with O0 on ARM, AArch64 and X86.
Since at O0, explicit copies via SplitCSR may not be removed even if
they are unnecessary, we choose not to use SplitCSR at O0.

llvm-svn: 263855
2016-03-18 23:38:49 +00:00
Tim Northover 498c56c240 ARM: stop asserting on weird <3 x Ty> vectors in ISelLowering.
llvm-svn: 263741
2016-03-17 20:10:28 +00:00
Saleem Abdulrasool 071a099102 ARM: Revert SVN r253865, 254158, fix windows division
The two changes together weakened the test and caused a regression with division
handling in MSVC mode.  They were applied to avoid an assertion being triggered
in the block frequency analysis.  However, the underlying problem was simply
being masked rather than solved properly.  Address the actual underlying problem
and revert the changes.  Rather than analyze the cause of the assertion, the
division failure was assumed to be an overflow.

The underlying issue was a subtle bug in the BB construction in the emission of
the div-by-zero check (WIN__DBZCHK).  We did not construct the proper successor
information in the basic blocks, nor did we update the PHIs associated with the
basic block when we split them.  This would result in assertions being triggered
in the block frequency analysis pass.

Although the original tests are being removed, the tests themselves performed
very little in terms of validation but merely tested that we did not assert when
generating code.  Update this with new tests that actually ensure that we do not
regress on the code generation.

llvm-svn: 263714
2016-03-17 14:10:49 +00:00
Alexandros Lamprineas 843164242e [ARM] Cortex-R8 support
This patch adds Cortex-R8 to Target Parser and TableGen.
It also adds CodeGen tests for the build attributes.

Patch by Pablo Barrio.

Differential Revision: http://reviews.llvm.org/D17925

llvm-svn: 263132
2016-03-10 17:38:41 +00:00
Saleem Abdulrasool 1632fe1f77 ARM: follow up improvements for SVN r263118
The initial change was insufficiently complete for always getting the semantics
of __builtin_longjmp correct.  The builtin is translated into a
`tInt_eh_sjlj_longjmp` DAG node.  This node set R7 as clobbered.  However, the
code would then follow up with a clobber of R11.  I had failed to notice the
imp-def,kill on R7 in the isel.  Unfortunately, it seems that it is not possible
to conditionalise the Defs list via an !if.  Instead, construct a new parallel
WIN node and prefer that when targeting windows.  This ensures that we now both
correctly model the __builtin_longjmp as well as construct the frame in a more
ABI conformant manner.

llvm-svn: 263123
2016-03-10 16:26:37 +00:00
Saleem Abdulrasool 8b30f9854e ARM: correct __builtin_longjmp on WoA
WoA uses r11 as the FP even though it is a pure thumb-2 environment in contrast
to AAPCS which states r7.  This adjusts __builtin_longjmp to not clobber r7 and
to properly restore the frame pointer on execution.

llvm-svn: 263118
2016-03-10 15:11:09 +00:00
Renato Golin 175c6d6d95 [ARM] Merging 64-bit divmod lib calls into one
When div+rem calls on the same arguments are found, the ARM back-end merges the
two calls into one __aeabi_divmod call for up to 32-bits values. However,
for 64-bit values, which also have a lib call (__aeabi_ldivmod), it wasn't
merging the calls, and thus calling ldivmod twice and spilling the temporary
results, which generated pretty bad code.

This patch legalises 64-bit lib calls for divmod, so that now all the spilling
and the second call are gone. It also relaxes the DivRem combiner a bit on the
legal type check, since it was already checking for isLegalOrCustom on every
value, so the extra check for isTypeLegal was redundant.

Second attempt, creating TLI.isOperationCustom like isOperationExpand, to make
sure we only emit valid types or the ones that were explicitly marked as custom.
Now, passing check-all and test-suite on x86, ARM and AArch64.

This patch fixes PR17193 (and a long time FIXME in the tests).

llvm-svn: 262738
2016-03-04 19:19:36 +00:00
NAKAMURA Takumi f2b521ffc5 llvm/test/CodeGen/ARM/rem_crash.ll: Avoid unsupported targets to specify explicit triple.
We will see it for targeting win32;

  LLVM ERROR: CPU: 'generic' does not support ARM mode execution!

llvm-svn: 262668
2016-03-03 22:38:39 +00:00
Renato Golin f824ced6a1 Making rem_crash.ll target-specific
This test failed in some ARM bots after a divmod change because it was
running on a native llc, instead of targeted one. This makes sure the test
is target-specific (as intended), and also copies to ARM and AArch64
directories. If it is also supposed to work on other architectures, I'll
leave as an exercise to the respective maintainers.

llvm-svn: 262620
2016-03-03 14:01:10 +00:00
Renato Golin 3d78271eac Revert "[ARM] Merging 64-bit divmod lib calls into one"
This reverts commit r262507, which broke some ARM buildbots.

llvm-svn: 262594
2016-03-03 08:57:44 +00:00
Renato Golin 93e42d9934 [ARM] Merging 64-bit divmod lib calls into one
When div+rem calls on the same arguments are found, the ARM back-end merges the
two calls into one __aeabi_divmod call for up to 32-bits values. However,
for 64-bit values, which also have a lib call (__aeabi_ldivmod), it wasn't
merging the calls, and thus calling ldivmod twice and spilling the temporary
results, which generated pretty bad code.

This patch legalises 64-bit lib calls for divmod, so that now all the spilling
and the second call are gone. It also relaxes the DivRem combiner a bit on the
legal type check, since it was already checking for isLegalOrCustom on every
value, so the extra check for isTypeLegal was redundant.

This patch fixes PR17193 (and a long time FIXME in the tests).

llvm-svn: 262507
2016-03-02 19:35:45 +00:00
Matthias Braun f290912d22 ARM: Introduce conservative load/store optimization mode
Most of the time ARM has the CCR.UNALIGN_TRP bit set to false which
means that unaligned loads/stores do not trap and even extensive testing
will not catch these bugs. However the multi/double variants are not
affected by this bit and will still trap. In effect a more aggressive
load/store optimization will break existing (bad) code.

These bugs do not necessarily manifest in the broken code where the
misaligned pointer is formed but often later in perfectly legal code
where it is accessed. This means recompiling system libraries (which
have no alignment bugs) with a newer compiler will break existing
applications (with alignment bugs) that worked before.

So (under protest) I implemented this safe mode which limits the
formation of multi/double operations to cases that are not affected by
user code (stack operations like spills/reloads) or cases where the
normal operations trap anyway (floating point load/stores). It is
disabled by default.

Differential Revision: http://reviews.llvm.org/D17015

llvm-svn: 262504
2016-03-02 19:20:00 +00:00
Tim Northover d32f8e60bf ARM: sink atomic release barrier as far as possible into cmpxchg.
DMB instructions can be expensive, so it's best to avoid them if possible. In
atomicrmw operations there will always be an attempted store so a release
barrier is always needed, but in the cmpxchg case we can delay the DMB until we
know we'll definitely try to perform a store (and so need release semantics).

In the strong cmpxchg case this isn't quite free: we must duplicate the LDREX
instructions to skip the barrier on subsequent iterations. The basic outline
becomes:

        ldrex rOld, [rAddr]
        cmp rOld, rDesired
        bne Ldone
        dmb
    Lloop:
        strex rRes, rNew, [rAddr]
        cbz rRes Ldone
        ldrex rOld, [rAddr]
        cmp rOld, rDesired
        beq Lloop
    Ldone:

So we'll skip this version for strong operations in "minsize" functions.

llvm-svn: 261568
2016-02-22 20:55:50 +00:00
Quentin Colombet e611698e84 [RegAllocFast] Properly track the physical register definitions on calls.
PR26485

llvm-svn: 261384
2016-02-20 00:32:29 +00:00
David Majnemer bd1b8c0889 [SjLjEHPrepare] Don't grab pointers to functions in doInitialization
Certain optimization passes (like globaldce) can prune function
declaration that SjLjEHPrepare assumed would exit when it'd
runOnFunction.

This fixes PR26669.

llvm-svn: 261303
2016-02-19 03:13:40 +00:00
Justin Lebar c75d566f56 When printing MIR, output to errs() rather than outs().
Summary:
Without this, this command

  $ llvm-run llc -stop-after machine-cp -o - <( echo '' )

outputs an error, because we close stdout twice -- once when closing the
file opened for "-o", and again when closing outs().

Also clarify in the outs() definition that you can't ever call it if you
want to open your own raw_fd_ostream on stdout.

Reviewers: jroelofs, tstellarAMD

Subscribers: jholewinski, qcolombet, dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D17422

llvm-svn: 261286
2016-02-19 00:18:46 +00:00
Mitch Bodart 3f42095776 Fix some erroneous lit test failures due to unlucky name of working directory.
Differential Revision:  http://reviews.llvm.org/D17044

llvm-svn: 261104
2016-02-17 16:35:18 +00:00
Saleem Abdulrasool f36005a358 ARM: support TLS for WoA
Add support for TLS access for Windows on ARM.  This generates a similar access
to MSVC for ARM.

The changes to the tablegen data is needed to support loading an external symbol
global that is not for a call.  The adjustments to the DAG to DAG transforms are
needed to preserve the 32-bit move.

llvm-svn: 259676
2016-02-03 18:21:59 +00:00
Renato Golin 6027dd38ef [ARM] Move GNUEABI divmod to __aeabi_divmod*
The GNU toolchain emits __aeabi_divmod for soft-divide on ARM cores
which happens to be a lot faster than __divsi3/__modsi3 when the core
has hardware divide instructions. Do the same here.

Fixes PR26450.

llvm-svn: 259657
2016-02-03 16:10:54 +00:00
Sjoerd Meijer ffe19f5245 Removed FeatureVFPOnlySP from the Cortex-R7 processor model
description and changed the regression test accordingly.
The default configuration of a Cortex-R7 is to implement the
VFPv3-D16 architecture and the feature line as it was is too
restrictive.

llvm-svn: 259480
2016-02-02 09:28:20 +00:00
Tim Northover c4093c3ced ARM: don't mangle DAG constant if it has more than one use
The basic optimisation was to convert (mul $LHS, $complex_constant) into
roughly "(shl (mul $LHS, $simple_constant), $simple_amt)" when it was expected
to be cheaper. The original logic checks that the mul only has one use (since
we're mangling $complex_constant), but when used in even more complex
addressing modes there may be an outer addition that can pick up the wrong
value too.

I *think* the ARM addressing-mode problem is actually unreachable at the
moment, but that depends on complex assessments of the profitability of
pre-increment addressing modes so I've put a real check in there instead of an
assertion.

llvm-svn: 259228
2016-01-29 19:18:46 +00:00
Alexandros Lamprineas 8c26e7c647 [ARM] Emit trap instruction using .inst directive
The trap instruction is emitted as a data-in-text rather
than an instruction. This patch uses the .inst directive
for emitting trap.

Differential Revision: http://reviews.llvm.org/D16684

llvm-svn: 259182
2016-01-29 10:23:32 +00:00
David Majnemer bff6b581e2 Address buildbot fallout from r259065
llvm-svn: 259074
2016-01-28 18:59:04 +00:00
Tim Northover 042a6c1fe1 ARMv7k: base ABI decision on v7k Arch rather than watchos OS.
Various bits we want to use the new ABI actually compile with "-arch armv7k
-miphoneos-version-min=9.0". Not ideal, but also not ridiculous given how
slices work.

llvm-svn: 258975
2016-01-27 19:32:29 +00:00