Matt Arsenault [Fri, 26 Sep 2014 17:55:03 +0000 (17:55 +0000)]
R600/SI Allow same SGPR to be used for multiple operands
Instead of moving the first SGPR that is different than the first,
legalize the operand that requires the fewest moves if one
SGPR is used for multiple operands.
This saves extra moves and is also required for some instructions
which require that the same operand be used for multiple operands.
Matt Arsenault [Fri, 26 Sep 2014 17:54:59 +0000 (17:54 +0000)]
R600/SI: Partially move operand legalization to post-isel hook.
Disable the SGPR usage restriction parts of the DAG legalizeOperands.
It now should only be doing immediate folding until it can be replaced
later. The real legalization work is now done by the other
SIInstrInfo::legalizeOperands
Matt Arsenault [Fri, 26 Sep 2014 17:54:54 +0000 (17:54 +0000)]
R600/SI: Implement findCommutedOpIndices
The base implementation of commuteInstruction is used
in some cases, but it turns out this has been broken for a
long time since modifiers were inserted between the real operands.
The base implementation of commuteInstruction also fails on immediates,
which also needs to be fixed.
Matt Arsenault [Fri, 26 Sep 2014 17:54:52 +0000 (17:54 +0000)]
R600/SI: Don't move operands that are required to be SGPRs
e.g. v_cndmask_b32 requires the condition operand be an SGPR.
If one of the source operands were an SGPR, that would be considered
the one SGPR use and the condition operand would be illegally moved.
Matt Arsenault [Fri, 26 Sep 2014 17:54:46 +0000 (17:54 +0000)]
R600/SI: Don't assert on exotic operand types
This needs a test, but I'm not sure if it is currently possible and
I originally hit it due to a bug. Right now the only global address
operands have no reason to be VALU instructions, although it
theoretically could be a problem.
Matt Arsenault [Fri, 26 Sep 2014 17:54:43 +0000 (17:54 +0000)]
R600/SI: Fix using wrong operand indices when commuting
No test since the current SIISelLowering::legalizeOperands
effectively hides this, and the general uses seem to only fire
on SALU instructions which don't have modifiers between
the operands.
When trying to use legalizeOperands immediately after
instruction selection, it now sees a lot more patterns
it did not see before which break on this.
Matt Arsenault [Fri, 26 Sep 2014 17:54:38 +0000 (17:54 +0000)]
R600/SI: Remove apparently dead code in legalizeOperands
No tests hit this, and I don't see any way a GlobalAddress
node would survive beyond lowering on SI. It it would, the
move should probably be inserted by selection.
David Peixotto [Fri, 26 Sep 2014 17:48:40 +0000 (17:48 +0000)]
Ignore annotation function calls in cost computation
The annotation instructions are dropped during codegen and have no
impact on size. In some cases, the annotations were preventing the
unroller from unrolling a loop because the annotation calls were
pushing the cost over the unrolling threshold.
[x86] In the new vector shuffle lowering, when trying to do another
layer of tie-breaking sorting, it really helps to check that you're in
a tie first. =] Otherwise the whole thing cycles infinitely. Test case
added, another one found through fuzz testing.
[x86] Fix a large collection of bugs that crept in as I fleshed out the
AVX support.
New test cases included. Note that none of the existing test cases
covered these buggy code paths. =/ Also, it is clear from this that
SHUFPS and SHUFPD are the most bug prone shuffle instructions in x86. =[
These were all detected by fuzz-testing. (I <3 fuzz testing.)
Elide repeated register operand in Thumb1 instructions
This patch makes the ARM backend transform 3 operand instructions such as
'adds/subs' to the 2 operand version of the same instruction if the first
two register operands are the same.
Example: 'adds r0, r0, #1' will is transformed to 'adds r0, #1'.
Currently for some instructions such as 'adds' if you try to assemble
'adds r0, r0, #8' for thumb v6m the assembler would throw an error message
because the immediate cannot be encoded using 3 bits.
The backend should be smart enough to transform the instruction to
'adds r0, #8', which allows for larger immediate constants.
The SSE rsqrt instruction (a fast reciprocal square root estimate) was
grouped in the same scheduling IIC_SSE_SQRT* class as the accurate (but very
slow) SSE sqrt instruction. For code which uses rsqrt (possibly with
newton-raphson iterations) this poor scheduling was affecting performances.
This patch splits off the rsqrt instruction from the sqrt instruction scheduling
classes and creates new IIC_SSE_RSQER* classes with latency values based on
Agner's table.
Store TypeUnits in a SmallVector<DWARFUnitSection> instead of a single DWARFUnitSection.
Summary:
There will be multiple TypeUnits in an unlinked object that will be extracted
from different sections. Now that we have DWARFUnitSection that is supposed
to represent an input section, we need a DWARFUnitSection<TypeUnit> per
input .debug_types section.
Once this is done, the interface is homogenous and we can move the Section
parsing code into DWARFUnitSection.
Daniel Sanders [Fri, 26 Sep 2014 10:06:12 +0000 (10:06 +0000)]
[mips] Generalize the handling of f128 return values to support f128 arguments.
Summary:
This will allow us to handle f128 arguments without duplicating code from
CCState::AnalyzeFormalArguments() or CCState::AnalyzeCallOperands().
Eric Christopher [Fri, 26 Sep 2014 01:44:08 +0000 (01:44 +0000)]
Add the first backend support for on demand subtarget creation
based on the Function. This is currently used to implement
mips16 support in the mips backend via the existing module
pass resetting the subtarget.
Things to note:
a) This involved running resetTargetOptions before creating a
new subtarget so that code generation options like soft-float
could be recognized when creating the new subtarget. This is
to deal with initialization code in isel lowering that only
paid attention to the initial value.
b) Many of the existing testcases weren't using the soft-float
feature correctly. I've corrected these based on the check
values assuming that was the desired behavior.
c) The mips port now pays attention to the target-cpu and
target-features strings when generating code for a particular
function. I've removed these from one function where the
requested cpu and features didn't match the check lines in
the testcase.
Eric Christopher [Fri, 26 Sep 2014 01:44:05 +0000 (01:44 +0000)]
Add a FIXME to TargetMachine to remove the function specific
code generation options from TargetMachine. This will depend
upon Function + TargetSubtargetInfo based code generation at
which point resetTargetOptions and this code can be removed.
Adam Nemet [Thu, 25 Sep 2014 23:48:49 +0000 (23:48 +0000)]
[AVX512] Pull pattern for subvector extract into the instruction definition
No functional change.
I initially thought that pulling the Pat<> into the instruction pattern was
not possible because it was doing a transform on the index in order to convert
it from a per-element (extract_subvector) index into a per-chunk (vextract*x4)
index.
Turns out this also works inside the pattern because the vextract_extract
PatFrag has an OperandTransform EXTRACT_get_vextract{128,256}_imm, so the
index in $idx goes through the same conversion.
The existing test CodeGen/X86/avx512-insert-extract.ll extended in the
previous commit provides coverage for this change.
Adam Nemet [Thu, 25 Sep 2014 23:48:45 +0000 (23:48 +0000)]
[AVX512] Refactor subvector extracts
No functional change.
These are now implemented as two levels of multiclasses heavily relying on the
new X86VectorVTInfo class. The multiclass at the first level that is called
with float or int provides the 128 or 256 bit subvector extracts. The second
level provides the register and memory variants and some more Pat<>s.
I've compared the td.expanded files before and after. One change is that
ExeDomain for 64x4 is SSEPackedDouble now. I think this is correct, i.e. a
bugfix.
(BTW, this is the change that was blocked on the recent tablegen fix. The
class-instance values X86VectorVTInfo inside vextract_for_type weren't
properly evaluated.)
[MachineSink+PGO] Teach MachineSink to use BlockFrequencyInfo
Machine Sink uses loop depth information to select between successors BBs to
sink machine instructions into, where BBs within smaller loop depths are
preferable. This patch adds support for choosing between successors by using
profile information from BlockFrequencyInfo instead, whenever the information
is available.
Tested it under SPEC2006 train (average of 30 runs for each program); ~1.5%
execution speedup in average on x86-64 darwin.
Nick Kledzik [Thu, 25 Sep 2014 20:30:58 +0000 (20:30 +0000)]
[Support] Add type-safe alternative to llvm::format()
llvm::format() is somewhat unsafe. The compiler does not check that integer
parameter size matches the %x or %d size and it does not complain when a
StringRef is passed for a %s. And correctly using a StringRef with format() is
ugly because you have to convert it to a std::string then call c_str().
The cases where llvm::format() is useful is controlling how numbers and
strings are printed, especially when you want fixed width output. This
patch adds some new formatting functions to raw_streams to format numbers
and StringRefs in a type safe manner. Some examples:
OS << format_hex(255, 6) => "0x00ff"
OS << format_hex(255, 4) => "0xff"
OS << format_decimal(0, 5) => " 0"
OS << format_decimal(255, 5) => " 255"
OS << right_justify(Str, 5) => " foo"
OS << left_justify(Str, 5) => "foo "
Tom Stellard [Thu, 25 Sep 2014 18:59:22 +0000 (18:59 +0000)]
SelectionDAG: Remove #if NDEBUG from check for a post-isel hook
The InstrEmitter will skip the check of MI.hasPostISelHook()
before calling AdjustInstrPostInstrSelection() when NDEBUG
is not defined.
This was added in r140228, and I'm not sure if it is intentional or not,
but it is a likely source for bugs, because it means with
Release+Asserts builds you can forget to set the hasPostISelHook
flag on TableGen definitions and AdjustInstrPostInstrSelection() will
still be called.
Robin Morisset [Thu, 25 Sep 2014 17:27:43 +0000 (17:27 +0000)]
Lower idempotent RMWs to fence+load
Summary:
I originally tried doing this specifically for X86 in the backend in D5091,
but it was rather brittle and generally running too late to be general.
Furthermore, other targets may want to implement similar optimizations.
So I reimplemented it at the IR-level, fitting it into AtomicExpandPass
as it interacts with that pass (which could not be cleanly done before
at the backend level).
This optimization relies on a new target hook, which is only used by X86
for now, as the correctness of the optimization on other targets remains
an open question. If it is found correct on other targets, it should be
trivial to enable for them.
Details of the optimization are discussed in D5091.
These instructions do not indicate they are extendable or the
number of bits in the extendable operand. Rename to match
architected names. Add a testcase for the intrinsics.
Daniel Sanders [Thu, 25 Sep 2014 12:15:05 +0000 (12:15 +0000)]
[mips] Add CCValAssign::[ASZ]ExtUpper and CCPromoteToUpperBitsInType and handle struct's correctly on big-endian N32/N64 return values.
Summary:
The N32/N64 ABI's require that structs passed in registers are laid out
such that spilling the register with 'sd' places the struct at the lowest
address. For little endian this is trivial but for big-endian it requires
that structs are shifted into the upper bits of the register.
We also require that structs passed in registers have the 'inreg'
attribute for big-endian N32/N64 to work correctly. This is because the
tablegen-erated calling convention implementation only has access to the
lowered form of struct arguments (one or more integers of up to 64-bits
each) and is unable to determine the original type.
On ARM NEON, VAND with immediate (16/32 bits) is an alias to VBIC ~imm with
the same type size. Adding that logic to the parser, and generating VBIC
instructions from VAND asm files.
This patch also fixes the validation routines for NEON splat immediates which
were wrong.
[x86] Teach the new vector shuffle lowering to use AVX2 instructions for
v4f64 and v8f32 shuffles when they are lane-crossing. We have fully
general lane-crossing permutation functions in AVX2 that make this easy.
Part of this also changes exactly when and how these vectors are split
up when we don't have AVX2. This isn't always a win but it usually is
a win, so on the balance I think its better. The primary regressions are
all things that just need to be fixed anyways such as modeling when
a blend can be completely accomplished via VINSERTF128, etc.
Also, this highlights one of the few remaining big features: we do
a really poor job of inserting elements into AVX registers efficiently.
This completes almost all of the big tricks I have in mind for AVX2. The
only things left that I plan to add:
1) element insertion smarts
2) palignr and other fairly specialized lowerings when they happen to
apply
[x86] Teach the new vector shuffle lowering a fancier way to lower
256-bit vectors with lane-crossing.
Rather than immediately decomposing to 128-bit vectors, try flipping the
256-bit vector lanes, shuffling them and blending them together. This
reduces our worst case shuffle by a pretty significant margin across the
board.
Oliver Stannard [Thu, 25 Sep 2014 10:02:05 +0000 (10:02 +0000)]
[Thumb2] BXJ should be undefined for v7M, v8A
The Thumb2 BXJ instruction (Branch and Exchange Jazelle) is not
defined for v7M or v8A. It is defined for all other Thumb2-supporting
architectures (v6T2, v7A and v7R).
[x86] Fix an oversight in the v8i32 path of the new vector shuffle
lowering where it only used the mask of the low 128-bit lane rather than
the entire mask.
This allows the new lowering to correctly match the unpack patterns for
v8i32 vectors.
For reference, the reason that we check for the the entire mask rather
than checking the repeated mask is because the repeated masks don't
abide by all of the invariants of normal masks. As a consequence, it is
safer to use the full mask with functions like the generic equivalence
test.
[x86] Rearrange the code for v16i16 lowering a bit for clarity and to
reduce the amount of checking we do here.
The first realization is that only non-crossing cases between 128-bit
lanes are handled by almost the entire function. It makes more sense to
handle the crossing cases first.
THe second is that until we actually are going to generate fancy shared
lowering strategies that use the repeated semantics of the v8i16
lowering, we should waste time checking for repeated masks. It is
simplest to directly test for the entire unpck masks anyways, so we
gained nothing from this.
This also matches the structure of v32i8 more closely.
I made a mistake in the previous commit and produced the wrong pattern.
Fix that. Also make one more shuffle pattern byte-based rather than
word-based, and add two more blend patterns.
[x86] Re-work a bunch of the v32i8 test cases to actually involve byte
shuffles rather than word shuffles.
As you might guess, these were built starting from the word shuffle test
cases and I failed to properly port a bunch of them and left them as
widened word shuffle test cases. We still have a couple of tests that
check our ability to widen shuffles, but now we will test the actual
byte shuffle quite a bit better.
MC: Use @IMGREL instead of @IMGREL32, which we can't parse
Nico Rieck added support for this 32-bit COFF relocation some time ago
for Win64 stuff. It appears that as an oversight, the assembly output
used "foo"@IMGREL32 instead of "foo"@IMGREL, which is what we can parse.
Sadly, there were actually tests that took in IMGREL and put out
IMGREL32, and we didn't notice the inconsistency. Oh well. Now LLVM can
assemble it's own output with slightly more fidelity.
[x86] Fix the v16i16 blend logic I added in the prior commit and add the
missing test cases for it.
Unsurprisingly, without test cases, there were bugs here. Surprisingly,
this bug wasn't caught at compile time. Yep, there is an X86ISD::BLENDV.
It isn't wired to anything. Oops. I'll fix than next.
llvm-cov: Combine segments that cover the same location
If we have multiple coverage counts for the same segment, we need to
add them up rather than arbitrarily choosing one. This fixes that and
adds a test with template instantiations to exercise it.
[x86] Implement v16i16 support with AVX2 in the new vector shuffle
lowering.
This also implements the fancy blend lowering for v16i16 using AVX2 and
teaches the X86 backend to print shuffle masks for 256-bit PSHUFB
and PBLENDW instructions. It also makes the mask decoding correct for
PBLENDW instructions. The yaks, they are legion.
Tests are updated accordingly. There are some missing tests for the
VBLENDVB lowering, but I'll add those in a follow-up as this commit has
accumulated enough cruft already.
Kevin Enderby [Wed, 24 Sep 2014 23:08:22 +0000 (23:08 +0000)]
Flush out enough of llvm-objdump’s SymbolizerSymbolLookUp() for Mach-O files to
get the literal string “Hello world” printed as a comment on the instruction
that loads the pointer to it. For now this is just for x86_64. So for object
files with relocation entries it produces things like:
leaq L_.str(%rip), %rax ## literal pool for: "Hello world\n"
and similar for fully linked images like executables:
leaq 0x4f(%rip), %rax ## literal pool for: "Hello world\n"
Also to allow testing against darwin’s otool(1), I hooked up the existing
-no-show-raw-insn option to the Mach-O parser code, added the new Mach-O
only -full-leading-addr option to match otool(1)'s printing of addresses and
also added the new -print-imm-hex option.
For biendian targets like ARM and AArch64, it is useful to have the
output of the llvm-dwarfdump and llvm-objdump report the endianness
used when the object files were generated.
This change fixes the ARM and AArch64 relocation visitors in
RelocVisitor. They were unconditionally assuming the object data are
little-endian. Tests have been added to ensure that the
llvm-dwarfdump utility does not crash when processing big-endian
object files.
This change replaces the brittle if/else chain of string comparisons
with a switch statement on the detected target triple, removing the
need for testing arbitrary architecture names returned from
getFileFormatName, whose primary purpose seems to be for display
(user-interface) purposes. The visitor now takes a reference to the
object file, rather than its arbitrary file format name to figure out
whether the file is a 32 or 64-bit object file and what the detected
target triple is.
A set of tests have been added to help show that the refactoring processes
relocations for the same targets as the original code.
For biendian targets like ARM and AArch64, it is useful to have the
output of the llvm-dwarfdump and llvm-objdump report the endianness
used when the object files were generated.
This change fixes the ARM and AArch64 relocation visitors in
RelocVisitor. They were unconditionally assuming the object data are
little-endian. Tests have been added to ensure that the
llvm-dwarfdump utility does not crash when processing big-endian
object files.
This change replaces the brittle if/else chain of string comparisons
with a switch statement on the detected target triple, removing the
need for testing arbitrary architecture names returned from
getFileFormatName, whose primary purpose seems to be for display
(user-interface) purposes. The visitor now takes a reference to the
object file, rather than its arbitrary file format name to figure out
whether the file is a 32 or 64-bit object file and what the detected
target triple is.
A set of tests have been added to help show that the refactoring processes
relocations for the same targets as the original code.
David Peixotto [Wed, 24 Sep 2014 16:48:31 +0000 (16:48 +0000)]
Fix assertion in LICM doFinalization()
The doFinalization method checks that the LoopToAliasSetMap is
empty. LICM populates that map as it runs through the loop nest,
deleting the entries for child loops as it goes. However, if a child
loop is deleted by another pass (e.g. unrolling) then the loop will
never be deleted from the map because LICM walks the loop nest to
find entries it can delete.
The fix is to delete the loop from the map and free the alias set
when the loop is deleted from the loop nest.
Moritz Roth [Wed, 24 Sep 2014 16:35:50 +0000 (16:35 +0000)]
[Thumb] Make load/store optimizer less conservative.
If it's safe to clobber the condition flags, we can do a few extra things:
it's then possible to reset the base register writeback using a SUBS, so
we can try to merge even if the base register isn't dead after the merged
instruction.
This is effectively a (heavily bug-fixed) rewrite of r208992.
Oliver Stannard [Wed, 24 Sep 2014 14:20:01 +0000 (14:20 +0000)]
[Thumb] 32-bit encodings of 'cps' are not valid for v7M
v7M only allows the 16-bit encoding of the 'cps' (Change Processor
State) instruction, and does not have the 32-bit encoding which is
valid from v6T2 onwards.
[x86] Teach the instruction lowering to add comments describing constant
pool data being loaded into a vector register.
The comments take the form of:
# ymm0 = [a,b,c,d,...]
# xmm1 = <x,y,z...>
The []s are used for generic sequential data and the <>s are used for
specifically ConstantVector loads. Undef elements are printed as the
letter 'u', integers in decimal, and floating point values as floating
point values. Suggestions on improving the formatting or other aspects
of the display are very welcome.
My primary use case for this is to be able to FileCheck test masks
passed to vector shuffle instructions in-register. It isn't fantastic
for that (no decoding special zeroing semantics or other tricks), but it
at least puts the mask onto an instruction line that could reasonably be
checked. I've updated many of the new vector shuffle lowering tests to
leverage this in their test cases so that we're actually checking the
shuffle masks remain as expected.
Before implementing this, I tried a *bunch* of different approaches.
I looked into teaching the MCInstLower code to scan up the basic block
and find a definition of a register used in a shuffle instruction and
then decode that, but this seems incredibly brittle and complex.
I talked to Hal a lot about the "right" way to do this: attach the raw
shuffle mask to the instruction itself in some form of unencoded
operands, and then use that to emit the comments. I still think that's
the optimal solution here, but it proved to be beyond what I'm up for
here. In particular, it seems likely best done by completing the
plumbing of metadata through these layers and attaching the shuffle mask
in metadata which could have fully automatic dropping when encoding an
actual instruction.