r187116 moved compare-and-branch generation from the instruction-selection
pass to the peephole optimizer (via optimizeCompare). It turns out that even
this is a bit too early. Fused compare-and-branch instructions don't
interact well with predication, where a CC result is needed. They also
make it harder to reuse the CC side-effects of earlier instructions
(not yet implemented, but the subject of a later patch).
Another problem was that the AnalyzeBranch family of routines weren't
handling compares and branches, so we weren't able to reverse the fused
form in cases where we would reverse a separate branch. This could have
been fixed by extending AnalyzeBranch, but given the other problems,
I've instead moved the fusing to the long-branch pass, which is also
responsible for the opposite transformation: splitting out-of-range
compares and branches into separate compares and long branches.
I've added a test for the AnalyzeBranch problem. A test for the
predication problem is included in the next patch, which fixes a bug
in the choice of CC mask.
llvm-svn: 187494
r186399 aggressively used the RISBG instruction for immediate ANDs,
both because it can handle some values that AND IMMEDIATE can't,
and because it allows the destination register to be different from
the source. I realized later while implementing the distinct-ops
support that it would be better to leave the choice up to
convertToThreeAddress() instead. The AND IMMEDIATE form is shorter
and is less likely to be cracked.
This is a problem for 32-bit ANDs because we assume that all 32-bit
operations will leave the high word untouched, whereas RISBG used in
this way will either clear the high word or copy it from the source
register. The patch uses the z196 instruction RISBLG for this instead.
This means that z10 will be restricted to NILL, NILH and NILF for
32-bit ANDs, but I think that should be OK for now. Although we're
using z10 as the base architecture, the optimization work is going
to be focused more on z196 and zEC12.
llvm-svn: 187492
All insertf*/extractf* functions replaced with insert/extract since we have insertf and inserti forms.
Added lowering for INSERT_VECTOR_ELT / EXTRACT_VECTOR_ELT for 512-bit vectors.
Added lowering for EXTRACT/INSERT subvector for 512-bit vectors.
Added a test.
llvm-svn: 187491
When simplifying a (or (and B A) (and C ~A)) to a (VBSL A B C) ensure that the
bitwidth of the second operands to both ands match before comparing the negation
of the values.
Split the check of the value of the second operands to the ands. Move the cast
and variable declaration slightly higher to make it slightly easier to follow.
Bug-Id: 16700
Signed-off-by: Saleem Abdulrasool <compnerd@compnerd.org>
llvm-svn: 187404
This is the first of many upcoming patches for PowerPC fast
instruction selection support. This patch implements the minimum
necessary for a functional (but extremely limited) FastISel pass. It
allows the table-generated portions of the selector to be created and
used, but in most cases selection will fall back to the DAG selector.
None of the block terminator instructions are implemented yet, and
most interesting instructions require some special handling.
Therefore there aren't any new test cases with this patch. There will
be quite a few tests coming with future patches.
This patch adds the make/CMake support for the new code (including
tablegen -gen-fast-isel) and creates the FastISel object for PPC64 ELF
only. It instantiates the necessary virtual functions
(TargetSelectInstruction, TargetMaterializeConstant,
TargetMaterializeAlloca, tryToFoldLoadIntoMI, and FastLowerArguments),
but of these, only TargetMaterializeConstant contains any useful
implementation. This is present since the table-generated code
requires the ability to materialize integer constants for some
instructions.
This patch has been tested by building and running the
projects/test-suite code with -O0. All tests passed with the
exception of a couple of long-running tests that time out using -O0
code generation.
llvm-svn: 187399
32-bit symbols have "_" as global prefix, but when forming the name of
COMDAT sections this prefix is ignored. The current behavior assumes that
this prefix is always present which is not the case for 64-bit and names
are truncated.
llvm-svn: 187356
The tests !defined(__ppc__) && !defined(__powerpc__) are not needed
or helpful when verifying that code is being compiled for a 64-bit
target. The simpler test provided by this revision is sufficient to
tell if the target is 64-bit.
llvm-svn: 187318
do in the SDag when lowering references to the GOT: use
ARMConstantPoolSymbol rather than creating a dummy global variable. The
computation of the alignment still feels weird (it uses IR types and
datalayout) but it preserves the exact previous behavior. This change
fixes the memory leak of the global variable detected on the valgrind
leak checking bot.
Thanks to Benjamin Kramer for pointing me at ARMConstantPoolSymbol to
handle this use case.
llvm-svn: 187303
me) should start watching this bot more as its catching lots of bugs.
The fix here is to not construct the global if we aren't going to need
it. That's cheaper anyways, and globals have highly predictable types in
practice. I've added an assert to catch skew between our manual testing
of the type and the actual type just for paranoia's sake.
Note that this pattern is actually fine in most globals because when you
build a global with a module it automatically is moved to be owned by
that module. But here, we're in isel and don't really want to do that.
The solution of not creating a global is simpler anyways.
llvm-svn: 187302
than once, and the second time through we leaked memory. Found thanks to
the vg-leak bot, but I can't locally reproduce it with valgrind. The
debugger confirms that it is in fact leaking here.
This whole code is totally gross. Why is initialize being called on each
runOnFunction??? Why aren't these OwningPtr<>s, and why aren't their
lifetimes better defined? Anyways, this is just a surgical change to
help out the leak checking bots.
llvm-svn: 187299
Merge consecutive if-regions if they contain identical statements.
Both transformations reduce number of branches. The transformation
is guarded by a target-hook, and is currently enabled only for +R600,
but the correctness has been tested on X86 target using a variety of
CPU benchmarks.
Patch by: Mei Ye
llvm-svn: 187278
Both GCC and LLVM will implicitly define __ppc__ and __powerpc__ for
all PowerPC targets, whether 32- or 64-bit. They will both implicitly
define __ppc64__ and __powerpc64__ for 64-bit PowerPC targets, and not
for 32-bit targets. We cannot be sure that all other possible
compilers used to compile Clang/LLVM define both __ppc__ and
__powerpc__, for example, so it is best to check for both when relying
on either inside the Clang/LLVM code base.
This patch makes sure we always check for both variants. In addition,
it fixes one unnecessary check in lib/Target/PowerPC/PPCJITInfo.cpp.
(At least one of __ppc__ and __powerpc__ should always be defined when
compiling for a PowerPC target, no matter which compiler is used, so
testing for them is unnecessary.)
There are some places in the compiler that check for other variants,
like __POWERPC__ and _POWER, and I have left those in place. There is
no need to add them elsewhere. This seems to be in Apple-specific
code, and I won't take a chance on breaking it.
There is no intended change in behavior; thus, no test cases are
added.
llvm-svn: 187248
CustomLowerNode was not being called during SplitVectorOperand,
meaning custom legalization could not be used by targets.
This also adds a test case for NVPTX that depends on this custom
legalization.
Differential Revision: http://llvm-reviews.chandlerc.com/D1195
Attempt to fix the buildbots by making the X86 test I just added platform independent
llvm-svn: 187202
This reverts commit 187198. It broke the bots.
The soft float test probably needs a -triple because of name differences.
On the hard float test I am getting a "roundss $1, %xmm0, %xmm0", instead of
"vroundss $1, %xmm0, %xmm0, %xmm0".
llvm-svn: 187201
CustomLowerNode was not being called during SplitVectorOperand,
meaning custom legalization could not be used by targets.
This also adds a test case for NVPTX that depends on this custom
legalization.
Differential Revision: http://llvm-reviews.chandlerc.com/D1195
llvm-svn: 187198
This patch provides basic support for powerpc64le as an LLVM target.
However, use of this target will not actually generate little-endian
code. Instead, use of the target will cause the correct little-endian
built-in defines to be generated, so that code that tests for
__LITTLE_ENDIAN__, for example, will be correctly parsed for
syntax-only testing. Code generation will otherwise be the same as
powerpc64 (big-endian), for now.
The patch leaves open the possibility of creating a little-endian
PowerPC64 back end, but there is no immediate intent to create such a
thing.
The LLVM portions of this patch simply add ppc64le coverage everywhere
that ppc64 coverage currently exists. There is nothing of any import
worth testing until such time as little-endian code generation is
implemented. In the corresponding Clang patch, there is a new test
case variant to ensure that correct built-in defines for little-endian
code are generated.
llvm-svn: 187179
Before the patch we took advantage of the fact that the compare and
branch are glued together in the selection DAG and fused them together
(where possible) while emitting them. This seemed to work well in practice.
However, fusing the compare so early makes it harder to remove redundant
compares in cases where CC already has a suitable value. This patch
therefore uses the peephole analyzeCompare/optimizeCompareInstr pair of
functions instead.
No behavioral change intended, but it paves the way for a later patch.
llvm-svn: 187116
These instructions are allowed to trap even if the condition is false,
so for now they are only used for "*ptr = (cond ? x : *ptr)"-style
constructs.
llvm-svn: 187111
There's no need to specify a flag to omit frame pointer elimination on non-leaf
nodes...(Honestly, I can't parse that option out.) Use the function attribute
stuff instead.
llvm-svn: 187093
This removes the need to store the asm variant in each row of the single table that existed before. Shaves ~16K off the size of X86AsmParser.o.
llvm-svn: 187026
These are really the same address space in hardware. The only
difference is that CONSTANT_ADDRESS uses a special cache for faster
access. When we are unable to use the constant kcache for some reason
(e.g. smaller types or lack of indirect addressing) then the instruction
selector must use GLOBAL_ADDRESS loads instead.
llvm-svn: 187006
When vectors are built from a single value, the ARM lowering issues a
scalar_to_vector node.
This node is then always morphed into a move from the general purpose unit to
the vector unit.
When the value comes from a load, this can be simplified into a vector load to
the right lane.
This patch changes the lowering of insert_vector_elt to expose a vector
friendly pattern in this situation.
This is a step toward fixing <rdar://problem/14170854>.
llvm-svn: 186999
This increases the number of opportunites we have for folding. With the
previous implementation we were unable to fold into any instructions
other than the first when multiple instructions were selected from a
single SDNode.
Reviewed-by: Vincent Lejeune <vljn at ovi.com>
llvm-svn: 186919
A side-effect of this is that now the compiler expects kernel arguments
to be 4-byte aligned.
Reviewed-by: Vincent Lejeune <vljn at ovi.com>
llvm-svn: 186916
This makes them consistent with 'bt' which already had this handling. gas has the same behavior. There have been discussions on the mailing list about determining size based on the immediate, but my goal here was just to remove the inconsistency.
llvm-svn: 186904
It only didn't use it before because it seems InstAlias handling in the asm printer fails to count tied operands so it tried to find an xor with 2 operands instead of the 3 it wfails to count tied.
llvm-svn: 186900
Enable parsing all 32 floating point control registers $0-31 and stop trying to
parse floating point condition code register $fcc0. Also, return ParseFail if
the operand being parsed is not in the expected format.
llvm-svn: 186861
instructions. With this patch:
1. ldr.n is recognized as mnemonic for the short encoding
2. ldr.w is recognized as menmonic for the long encoding
3. ldr will map to either short or long encodings depending on the size of the offset
llvm-svn: 186831
After Ulrich's r180677 (thanks!) TableGen is intelligent enough to
handle tied constraints involving complex operands properly, so
virtually all of the ARM custom converters are now unnecessary.
llvm-svn: 186810
indirect branches correctly. Under some circumstances, this led to the deletion
of basic blocks that were the destination of indirect branches. In that case it
left indirect branches to nowhere in the code.
This patch replaces, and is more general than either of the previous fixes for
indirect-branch-analysis issues, r181161 and r186461.
For other branches (not indirect) this refactor should have *almost* identical
behavior to the previous version. There are some corner cases where this
refactor is able to analyze blocks that the previous version could not (e.g.
this necessitated the update to thumb2-ifcvt2.ll).
<rdar://problem/14464830>
llvm-svn: 186735
The atomic tests assume the two-operand forms, so I've restricted them to z10.
Running and-01.ll, or-01.ll and xor-01.ll for z196 as well as z10 shows why
using convertToThreeAddress() is better than exposing the three-operand forms
first and then converting back to two operands where possible (which is what
I'd originally tried). Using the three-operand form first stops us from
taking advantage of NG, OG and XG for spills.
llvm-svn: 186683
This first step just adds definitions for SLLK, SRLK and SRAK.
The next patch will actually make use of them during codegen.
insn-bad.s tests that some form of error is reported when using these
instructions on z10. More work is needed to get the "instruction requires:
distinct-ops" that we'd ideally like, so I've stubbed that part out for now.
I'll come back and make it mandatory once the necessary changes are in.
llvm-svn: 186680
The original code only folded SRA into ROTATE ... SELECTED BITS
if there was no outer shift. This patch splits out that check
and generalises it slightly. The extra cases aren't really that
interesting, but this is paving the way for RNSBG support.
llvm-svn: 186571
In hindsight, using "RISBG" for something that can be any type of
R.SBG instruction was a bit confusing, so this renames it to RxSBG.
That might not be the best choice either, since there is an instruction
called RXSBG, but hopefully the lower-case letter stands out enough.
While there I fixed a couple of GNUisms that had crept in --
sorry about that!
llvm-svn: 186569
Support for dynamic stack alignments in the PPC backend has been unfinished, in
part because it depends on dynamic stack realignment (which I only just
recently implemented fully). Now we can also support dynamic allocas with
higher than the default target stack alignment (16 bytes).
In order to round-up the requested size to the maximum requested alignment, we
need an additional register to hold the rounded-up size. We're already using one
scavenged register to hold the previous stack-pointer value (which needs to be
stored with the signal-safe stdux update), and so when we have dynamic allocas
and a large alignment, we allocate two emergency spill slots for the scavenger.
llvm-svn: 186562
First, this changes the base-pointer implementation to remove an unnecessary
complication (and one that is incompatible with how builtin SjLj is
implemented): instead of using r31 as the base pointer when it is not needed as
a frame pointer, now the base pointer will always be r30 when needed.
Second, we introduce another pseudo register, BP, which is used just like the FP
pseudo register to refer to the base register before we know for certain what
register it will be.
Third, we now save BP into the jmp_buf, and restore r30 from that slot in
longjmp. If the function that called setjmp did not use a base pointer, then
r30 will be overwritten by the setjmp-calling-function's restore code. FP
restoration (which is restored into r31) works the same way.
llvm-svn: 186545
My patch 'r183551 - ARM FastISel integer sext/zext improvements' was incorrect when emitting ARM register-immediate ASR, LSL, LSR instructions: they are pseudo-instructions in ARMInstrInfo.td and I should have used MOVsi instead.
This is not an issue when code is generated through a .s file, but is an issue when generated straight to a .o (-filetype=obj).
llvm-svn: 186489
Because the builtin longjmp implementation uses a CTR-based indirect jump, when
the control flow arrives at the builtin setjmp call, the CTR register has
necessarily been clobbered. Correspondingly, this adds CTR to the list of
implicit definitions of the builtin setjmp pseudo instruction.
We don't need to add CTR to the implicit definitions of builtin longjmp
because, even though it does clobber the CTR register, the control flow cannot
return to inside the loop unless there is also a builtin setjmp call.
llvm-svn: 186488
This builds on some frame-lowering code that has existed since 2005 (r24224)
but was disabled in 2008 (r48188) because it needed base pointer support to
function correctly. This implementation follows the strategy suggested by Dale
Johannesen in r48188 where the following comment was added:
This does not currently work, because the delta between old and new stack
pointers is added to offsets that reference incoming parameters after the
prolog is generated, and the code that does that doesn't handle a variable
delta. You don't want to do that anyway; a better approach is to reserve
another register that retains to the incoming stack pointer, and reference
parameters relative to that.
And now we do exactly that. If we don't need a frame pointer, then we use r31
as a base pointer. If we do need a frame pointer, then we use r30 as a base
pointer. The base pointer retains the value of the stack pointer before it was
decremented in the prologue. We then use the base pointer to resolve all
negative frame indicies. The basic scheme follows that for base pointers in the
X86 backend.
We use a base pointer when we need to dynamically realign the incoming stack
pointer. This currently applies only to static objects (dynamic allocas with
large alignments, and base-pointer support in SjLj lowering will come in future
commits).
llvm-svn: 186478
block. Blocks that have an indirect branch terminator, even if it's not the
last terminator, should still be treated as unanalyzable.
<rdar://problem/14437274>
Reducing a useful regression test case is proving difficult - I hope to have
one soon.
llvm-svn: 186461
This adds an instruction alias to make the assembler recognize the alternate literal form: pli [PC, #+/-<imm>]
See A8.8.129 in the ARM ARM (DDI 0406C.b).
Fixes <rdar://problem/14403733>.
llvm-svn: 186459