Like the addi/addis instructions themselves, these pseudo instructions also
cannot have r0 as their register parameter (because it will be interpreted as
the value 0).
This is not yet testable because we don't yet allocate r0 (and even when we do,
any regression test would be very fragile because it would depend on the
register allocator heuristics).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178118 91177308-0d34-0410-b5e6-96231b3b80d8
Some implementation detail in the forgotten past required the link
register to be placed in the GPRC and G8RC register classes. This is
just wrong on the face of it, and causes several extra intersection
register classes to be generated. I found this was having evil
effects on instruction scheduling, by causing the wrong register class
to be consulted for register pressure decisions.
No code generation changes are expected, other than some minor changes
in instruction order. Seven tests in the test bucket required minor
tweaks to adjust to the new normal.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178114 91177308-0d34-0410-b5e6-96231b3b80d8
As Bill Schmidt pointed out to me, only on Darwin do we need to spill/restore
VRSAVE in the SjLj code. For non-Darwin, don't spill/restore VRSAVE (and I've
added some asserts to make sure that we're not).
As it turns out, we're not currently handling the Darwin case correctly (I've
added a FIXME in the test case). I've tried adding various implied register
definitions/uses to force the spill without success, so I'll need to address
this later.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178096 91177308-0d34-0410-b5e6-96231b3b80d8
As suggested by Bill Schmidt (in reviewing r178067), use the real register
number bit lengths (which is self-documenting, and prevents using illegal
numbers), and set only the relevant bits in HWEncoding (which defaults to 0).
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178077 91177308-0d34-0410-b5e6-96231b3b80d8
As pointed out by Jakob, we don't need to maintain a separate
register-numbering table. Instead we should let TableGen generate the table for
us from the information (already present) in PPCRegisterInfo.td.
TRI->getEncodingValue is now used to access register-encoding values.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178067 91177308-0d34-0410-b5e6-96231b3b80d8
Now that the register scavenger can support multiple spill slots, and PEI can
use virtual-register-based scavenging for multiple simultaneous registers, we
can use a virtual register for the transfer register in the CR spilling code.
This should eliminate the last place (outside of the prologue/epilogue) where
we depend on the unconditional availability of the r0 register. We will soon be
able to allocate it (in a somewhat restricted sense) as a GPR.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178060 91177308-0d34-0410-b5e6-96231b3b80d8
PPC's use of PEI's virtual-register-based scavenging functionality had
redefined the virtual registers (it was non-SSA). Now that PEI supports
dealing with instructions with multiple virtual registers, this can be
cleanup up to use multiple virtual registers and keep SSA form.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178059 91177308-0d34-0410-b5e6-96231b3b80d8
There remain a number of patterns that cannot (and should not)
be handled by the asm parser, in particular all the Pseudo patterns.
This commit marks those patterns as isCodeGenOnly.
No change in generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178008 91177308-0d34-0410-b5e6-96231b3b80d8
MCTargetDesc/PPCMCCodeEmitter.cpp current has code like:
if (isSVR4ABI() && is64BitMode())
Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_toc16));
else
Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_lo16));
This is a problem for the asm parser, since it requires knowledge of
the ABI / 64-bit mode to be set up. However, more fundamentally,
at this point we shouldn't make such distinctions anyway; in an assembler
file, it always ought to be possible to e.g. generate TOC relocations even
when the main ABI is one that doesn't use TOC.
Fortunately, this is actually completely unnecessary; that code was added
to decide whether to generate TOC relocations, but that information is in
fact already encoded in the VariantKind of the underlying symbol.
This commit therefore merges those fixup types into one, and then decides
which relocation to use based on the VariantKind.
No changes in generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178007 91177308-0d34-0410-b5e6-96231b3b80d8
As part of the the sequence generated to implement long double -> int
conversions, we need to perform an FADD in round-to-zero mode. This is
problematical since the FPSCR is not at all modeled at the SelectionDAG
level, and thus there is a risk of getting floating point instructions
generated out of sequence with the instructions to modify FPSCR.
The current code handles this by somewhat "special" patterns that in part
have dummy operands, and/or duplicate existing instructions, making them
awkward to handle in the asm parser.
This commit changes this by leaving the "FADD in round-to-zero mode"
as an atomic operation on the SelectionDAG level, and only split it up into
real instructions at the MI level (via custom inserter). Since at *this*
level the FPSCR *is* modeled (via the "RM" hard register), much of the
"special" stuff can just go away, and the resulting patterns can be used by
the asm parser.
No significant change in generated code expected.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178006 91177308-0d34-0410-b5e6-96231b3b80d8
The LDrs pattern is a duplicate of LD, except that it accepts memory
addresses where the displacement is a symbolLo64. An operand type
"memrs" is defined for just that purpose.
However, this wouldn't be necessary if the default "memrix" operand
type were to simply accept 64-bit symbolic addresses directly.
The only problem with that is that it uses "symbolLo", which is
hardcoded to 32-bit.
To fix this, this commit changes "memri" and "memrix" to use new
operand types for the memory displacement, which allow iPTR
instead of i32. This will also make address parsing easier to
implment in the asm parser.
No change in generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178005 91177308-0d34-0410-b5e6-96231b3b80d8
The ADDI/ADDI8 patterns are currently duplicated into ADDIL/ADDI8L,
which describe the same instruction, except that they accept a
symbolLo[64] operand instead of a s16imm[64] operand.
This duplication confuses the asm parser, and it actually not really
needed, since symbolLo[64] already accepts immediate operands anyway.
So this commit removes the duplicate patterns.
No change in generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178004 91177308-0d34-0410-b5e6-96231b3b80d8
This commit changes the ISEL patterns to use a CCBITRC operand
instead of a "pred" operand. This matches the actual instruction
text more directly, and simplifies use of ISEL with the asm parser.
In addition, this change allows some simplification of handling
the "pred" operand, as this is now only used by BCC.
No change in generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178003 91177308-0d34-0410-b5e6-96231b3b80d8
The BLR pattern cannot be recognized by the asm parser in its current form.
This complexity is due to an apparent attempt to enable conditional BLR
variants. However, none of those can ever be generated by current code;
the pattern is only ever created using the default "pred" operand.
To simplify the pattern and allow it to be recognized by the parser,
this commit removes those attempts at conditional BLR support.
When we later come back to actually add real conditional BLR, this
should probably be done via a fully generic conditional branch pattern.
No change in generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178002 91177308-0d34-0410-b5e6-96231b3b80d8
In PPCInstr64Bit.td, some branch patterns appear in a different sequence
than the corresponding 32-bit patterns in PPCInstrInfo.td.
To simplify future changes that affect both files, this commit moves
those patterns to rearrange them into a similar sequence.
No effect on generated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178001 91177308-0d34-0410-b5e6-96231b3b80d8
This commit updates the PowerPC back-end (PPCInstrInfo.td and
PPCInstr64Bit.td) to use types instead of register classes in
instruction patterns, along the lines of Jakob Stoklund Olesen's
changes in r177835 for Sparc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177890 91177308-0d34-0410-b5e6-96231b3b80d8
This commit updates the PowerPC back-end (PPCInstrInfo.td and
PPCInstr64Bit.td) to use types instead of register classes in
Pat patterns, along the lines of Jakob Stoklund Olesen's
changes in r177829 for Sparc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177889 91177308-0d34-0410-b5e6-96231b3b80d8
In order for the new ZERO register to be used with MC, etc. we need to specify
its register number (0).
Thanks to Kai for reporting the problem!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177833 91177308-0d34-0410-b5e6-96231b3b80d8
In preparation for using the new register scavenger capability for providing
more than one register simultaneously, specifically note functions that have
spilled VRSAVE (currently, this can happen only in functions that use the
setjmp intrinsic). As with CR spilling, such functions will need to provide two
emergency spill slots to the scavenger.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177832 91177308-0d34-0410-b5e6-96231b3b80d8
I recently added a BCL instruction definition as part of implementing SjLj
support. This can also be used to MCize bcl emission in the asm printer.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177830 91177308-0d34-0410-b5e6-96231b3b80d8
These spilling functions will eventually make use of the register scavenger,
however, they'll do so by taking advantage of PEI's virtual-register-based
delayed scavenging mechanism. As a result, these function parameters will not
be used, and can be removed.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177827 91177308-0d34-0410-b5e6-96231b3b80d8
The LR register is unconditionally reserved, and its spilling and restoration
is handled by the prologue/epilogue code. As a result, it is never explicitly
spilled by the register allocator.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177823 91177308-0d34-0410-b5e6-96231b3b80d8
This patch lets the register scavenger make use of multiple spill slots in
order to guarantee that it will be able to provide multiple registers
simultaneously.
To support this, the RS's API has changed slightly: setScavengingFrameIndex /
getScavengingFrameIndex have been replaced by addScavengingFrameIndex /
isScavengingFrameIndex / getScavengingFrameIndices.
In forthcoming commits, the PowerPC backend will use this capability in order
to implement the spilling of condition registers, and some special-purpose
registers, without relying on r0 being reserved. In some cases, spilling these
registers requires two GPRs: one for addressing and one to hold the value being
transferred.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177774 91177308-0d34-0410-b5e6-96231b3b80d8
We currently have a duplicated set of call instruction patterns depending
on the ABI to be followed (Darwin vs. Linux). This is a bit odd; while the
different ABIs will result in different instruction sequences, the actual
instructions themselves ought to be independent of the ABI. And in fact it
turns out that the only nontrivial difference between the two sets of
patterns is that in the PPC64 Linux ABI, the instruction used for indirect
calls is marked to take X11 as extra input register (which is indeed used
only with that ABI to hold an incoming environment pointer for nested
functions). However, this does not need to be hard-coded at the .td
pattern level; instead, the C++ code expanding calls can simply add that
use, just like it adds uses for argument registers anyway.
No change in generated code expected.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177735 91177308-0d34-0410-b5e6-96231b3b80d8
Currently, the sub-operand of a memrr address that corresponds to what
hardware considers the base register is called "offreg", while the
sub-operand that corresponds to the offset is called "ptrreg".
To avoid confusion, this patch simply swaps the named of those two
sub-operands and updates all uses. No functional change is intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177734 91177308-0d34-0410-b5e6-96231b3b80d8
PPCTargetLowering::getPreIndexedAddressParts currently provides
the base part of a memory address in the offset result, and the
offset part in the base result. That swap is then undone again
when an MI instruction is generated (in PPCDAGToDAGISel::Select
for loads, and using .md Pat patterns for stores).
This patch reverts this double swap, to make common code and
back-end be in sync as to which part of the address is base
and which is offset.
To avoid performance regressions in certain cases, target code
now checks whether the choice of base register would be rejected
for pre-inc accesses by common code, and attempts to swap base
and offset again in such cases. (Overall, this means that now
pre-ice accesses are generated *more* frequently than before.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177733 91177308-0d34-0410-b5e6-96231b3b80d8
The iaddroff ComplexPattern is supposed to recognize displacement
expressions that have been processed by a SelectAddressRegImm,
which means it needs to accept TargetConstant and TargetGlobalAddress
nodes. Currently, it erroneously also accepts some other nodes,
in particular Constant and PPCISD::Lo.
While this problem is currently latent, it would cause wrong-code
bugs with a follow-on patch I'm about to commit, so this patch
tightens the ComplexPattern. The equivalent change is made in
PPCDAGToDAGISel::Select, where pre-inc load patterns are handled
(as opposed to store patterns, the loads are handled in C++ code
without making use of the .td ComplexPattern).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177732 91177308-0d34-0410-b5e6-96231b3b80d8
The xaddroff pattern is currently (mistakenly) used to recognize
the *base* register in pre-inc store patterns. This patch replaces
those uses by ptr_rc_nor0 (as is elsewhere done to match the base
register of an address), and removes the now unused ComplexPattern.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177731 91177308-0d34-0410-b5e6-96231b3b80d8
As Jakob pointed out in his review of r177423, having a shared ZERO
register between the 32- and 64-bit register classes causes this
odd G8RC_NOX0_and_GPRC_NOR0 class to be created. As recommended,
this adds a ZERO8 register which differentiates the 32- and 64-bit
zeros.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177683 91177308-0d34-0410-b5e6-96231b3b80d8
Thanks to Jakob for isolating the underlying problem from the
test case in r177423. The original commit had introduced
asymmetric copy operations, but these turned out to be a work-around
to the real problem (the use of == instead of hasSubClassEq in PPCCTRLoops).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177679 91177308-0d34-0410-b5e6-96231b3b80d8
This implements SJLJ lowering on PPC, making the Clang functions
__builtin_{setjmp/longjmp} functional on PPC platforms. The implementation
strategy is similar to that on X86, with the exception that a branch-and-link
variant is used to get the right jump address. Credit goes to Bill Schmidt for
suggesting the use of the unconditional bcl form (instead of the regular bl
instruction) to limit return-address-cache pollution.
Benchmarking the speed at -O3 of:
static jmp_buf env_sigill;
void foo() {
__builtin_longjmp(env_sigill,1);
}
main() {
...
for (int i = 0; i < c; ++i) {
if (__builtin_setjmp(env_sigill)) {
goto done;
} else {
foo();
}
done:;
}
...
}
vs. the same code using the libc setjmp/longjmp functions on a P7 shows that
this builtin implementation is ~4x faster with Altivec enabled and ~7.25x
faster with Altivec disabled. This comparison is somewhat unfair because the
libc version must also save/restore the VSX registers which we don't yet
support.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177666 91177308-0d34-0410-b5e6-96231b3b80d8
Although there is only one Altivec VRSAVE register, it is a member of
a register class, and we need the ability to spill it. Because this
register is normally callee-preserved and handled by special code this
has never before been necessary. However, this capability will be required by
a forthcoming commit adding SjLj support.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177654 91177308-0d34-0410-b5e6-96231b3b80d8
The old code used to lower FRAMEADDR tried to replicate the logic in the real
frame-lowering code that determines whether or not the frame pointer (r31) will
be used. When it seemed as through the frame pointer would not be used, the
stack pointer (r1) was used instead. Unfortunately, because the stack size is
not yet known, this does not work. Instead, this change introduces new
always-reserved pseudo-registers (FP and FP8) that are replaced during prologue
insertion with the real frame-pointer register (either r1 or r31).
It is important that this intrinsic always return a valid frame address because
it is used by Clang to store the frame address as part of code generation for
__builtin_setjmp.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177653 91177308-0d34-0410-b5e6-96231b3b80d8
All pre-increment load patterns need to set the mayLoad flag (since
they don't provide a DAG pattern).
This was missing for LHAUX8 and LWAUX, which is added by this patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177431 91177308-0d34-0410-b5e6-96231b3b80d8
As opposed to to pre-increment store patterns, the pre-increment
load patterns were already using standard memory operands, with
the sole exception of LHAU8.
As there's no real reason why LHAU8 should be different here,
this patch simply rewrites the pattern to also use a memri
operand, just like all the other patterns.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177430 91177308-0d34-0410-b5e6-96231b3b80d8
Currently, pre-increment store patterns are written to use two separate
operands to represent address base and displacement:
stwu $rS, $ptroff($ptrreg)
This causes problems when implementing the assembler parser, so this
commit changes the patterns to use standard (complex) memory operands
like in all other memory access instruction patterns:
stwu $rS, $dst
To still match those instructions against the appropriate pre_store
SelectionDAG nodes, the patch uses the new feature that allows a Pat
to match multiple DAG operands against a single (complex) instruction
operand.
Approved by Hal Finkel.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177429 91177308-0d34-0410-b5e6-96231b3b80d8
The tocentry operand class refers to 64-bit values (it is only used in 64-bit,
where iPTR is a 64-bit type), but its sole suboperand is designated as 32-bit
type. This causes a mismatch to be detected at compile-time with the TableGen
patch I'll check in shortly.
To fix this, this commit changes the suboperand to a 64-bit type as well.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177427 91177308-0d34-0410-b5e6-96231b3b80d8
Currently the PPC r0 register is unconditionally reserved. There are two reasons
for this:
1. r0 is treated specially (as the constant 0) by certain instructions, and so
cannot be used with those instructions as a regular register.
2. r0 is used as a temporary register in the CR-register spilling process
(where, under some circumstances, we require two GPRs).
This change addresses the first reason by introducing a restricted register
class (without r0) for use by those instructions that treat r0 specially. These
register classes have a new pseudo-register, ZERO, which represents the r0-as-0
use. This has the side benefit of making the existing target code simpler (and
easier to understand), and will make it clear to the register allocator that
uses of r0 as 0 don't conflict will real uses of the r0 register.
Once the CR spilling code is improved, we'll be able to allocate r0.
Adding these extra register classes, for some reason unclear to me, causes
requests to the target to copy 32-bit registers to 64-bit registers. The
resulting code seems correct (and causes no test-suite failures), and the new
test case covers this new kind of asymmetric copy.
As r0 is still reserved, no functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177423 91177308-0d34-0410-b5e6-96231b3b80d8
Remove an accidentally-added instruction definition and add a comment in the
test case. This is in response to a post-commit review by Bill Schmidt.
No functionality change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177404 91177308-0d34-0410-b5e6-96231b3b80d8
PPC64 supports unaligned loads and stores of 64-bit values, but
in order to use the r+i forms, the offset must be a multiple of 4.
Unfortunately, this cannot always be determined by examining the
immediate itself because it might be available only via a TOC entry.
In order to get around this issue, we additionally predicate the
selection of the r+i form on the alignment of the load or store
(forcing it to be at least 4 in order to select the r+i form).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177338 91177308-0d34-0410-b5e6-96231b3b80d8
This commit fixes an assert that would occur on loops with large constant counts
(like looping for ((uint32_t) -1) iterations on PPC64). The existing code did
not handle counts that it computed to be negative (asserting instead), but
these can be created with valid inputs.
This bug was discovered by bugpoint while I was attempting to isolate a
completely different problem.
Also, in writing test cases for the negative-count problem, I discovered that
the ori/lsi handling was broken (there was a typo which caused the logic that
was supposed to detect these pairs and extract the iteration count to always
fail). This has now also been corrected (and is covered by one of the new test
cases).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177295 91177308-0d34-0410-b5e6-96231b3b80d8
Because the initial-value constants had not been added to the list
of instructions considered for DCE the resulting code had redundant
constant-materialization instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177294 91177308-0d34-0410-b5e6-96231b3b80d8
This change cleans up two issues with Altivec register spilling:
1. The spilling code was inefficient (using two instructions, and add and a
load, when just one would do)
2. The code assumed that r0 would always be available (true for now, but this
will change)
The new code handles VR spilling just like GPR spills but forced into r+r mode.
As a result, when any VR spills are present, we must now always allocate the
register-scavenger spill slot.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177231 91177308-0d34-0410-b5e6-96231b3b80d8
As a follow-up to r158719, remove PPCRegisterInfo::avoidWriteAfterWrite.
Jakob pointed out in response to r158719 that this callback is currently unused
and so this has no effect (and the speedups that I thought that I had observed
as a result of implementing this function must have been noise).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177228 91177308-0d34-0410-b5e6-96231b3b80d8
Unaligned access is supported on PPC for non-vector types, and is generally
more efficient than manually expanding the loads and stores.
A few of the existing test cases were using expanded unaligned loads and stores
to test other features (like load/store with update), and for these test cases,
unaligned access remains disabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177160 91177308-0d34-0410-b5e6-96231b3b80d8
In preparation for the addition of other SIMD ISA extensions (such as QPX) we
need to make sure that all Altivec patterns are properly predicated on having
Altivec support.
No functionality change intended (one test case needed to be updated b/c it
assumed that Altivec intrinsics would be supported without enabling Altivec
support).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177152 91177308-0d34-0410-b5e6-96231b3b80d8
For spills into a large stack frame, the FI-elimination code uses the register
scavenger to obtain a free GPR for use with an r+r-addressed load or store.
When there are no available GPRs, the scavenger gets one by using its spill
slot. Previously, we were not always allocating that spill slot and the RS
would assert when the spill slot was needed.
I don't currently have a small test that triggered the assert, but I've
created a small regression test that verifies that the spill slot is now
added when the stack frame is sufficiently large.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177140 91177308-0d34-0410-b5e6-96231b3b80d8
Add the current PEI register scavenger as a parameter to the
processFunctionBeforeFrameFinalized callback.
This change is necessary in order to allow the PowerPC target code to
set the register scavenger frame index after the save-area offset
adjustments performed by processFunctionBeforeFrameFinalized. Only
after these adjustments have been made is it possible to estimate
the size of the stack frame.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177108 91177308-0d34-0410-b5e6-96231b3b80d8
Make requiresFrameIndexScavenging return true, and create virtual registers in
the spilling code instead of using the register scavenger directly. This makes
the target-level code simpler, and importantly, delays the scavenging until
after callee-saved register processing (which will be important for later
changes).
Also cleans up trackLivenessAfterRegAlloc (makes it inline in the header with
the other related functions). This makes it clear that it always returns true.
No functionality change intended.
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We used to add a spill slot for the register scavenger whenever the function
has a frame pointer. This is unnecessarily conservative: We may need the spill
slot for dynamic stack allocations, and functions with dynamic stack
allocations always have a FP, but we might also have a FP for other reasons
(such as the user explicitly disabling frame-pointer elimination), and we don't
necessarily need a spill slot for those functions.
The structsinregs test needed adjustment because it disables FP elimination.
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I don't think that it is otherwise clear how the overlapping offsets
are processed into distinct spill slots. Comment that this is done
in processFunctionBeforeFrameFinalized.
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Now that only the register-scavenger version of the CR spilling code remains,
we no longer need the Darwin R2 hack. Darwin can use R0 as a spare register in
any case where the System V ABI uses it (R0 is special architecturally, and so
is reserved under all common ABIs).
A few test cases needed to be updated to reflect the register-allocation changes.
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This removes the -disable-ppc[32|64]-regscavenger options; the code
that uses the register scavenger has been working well (and has been the default)
for some time, and we don't need options to enable the old (broken) CR spilling code.
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- ISD::SHL/SRL/SRA must have either both scalar or both vector operands
but TLI.getShiftAmountTy() so far only return scalar type. As a
result, backend logic assuming that breaks.
- Rename the original TLI.getShiftAmountTy() to
TLI.getScalarShiftAmountTy() and re-define TLI.getShiftAmountTy() to
return target-specificed scalar type or the same vector type as the
1st operand.
- Fix most TICG logic assuming TLI.getShiftAmountTy() a simple scalar
type.
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There's no need to generate a stack frame for PPC32 SVR4 when there are
no local variables assigned to the stack, i.e., when no red zone is needed.
(PPC64 supports a red zone, but PPC32 does not.)
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This removes a const_cast hack from PPCRegisterInfo::hasReservedSpillSlot().
The proper place to save the frame index for the CR spill slot is in the
PPCFunctionInfo object, not the PPCRegisterInfo object.
No new test cases, as this just reimplements existing function. Existing
tests such as test/CodeGen/PowerPC/crsave.ll are sufficient.
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to TargetFrameLowering, where it belongs. Incidentally, this allows us
to delete some duplicated (and slightly different!) code in TRI.
There are potentially other layering problems that can be cleaned up
as a result, or in a similar manner.
The refactoring was OK'd by Anton Korobeynikov on llvmdev.
Note: this touches the target interfaces, so out-of-tree targets may
be affected.
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Large code model is identical to medium code model except that the
addis/addi sequence for "local" accesses is never used. All accesses
use the addis/ld sequence.
The coding changes are straightforward; most of the patch is taken up
with creating variants of the medium model tests for large model.
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This patch implements the PPCDAGToDAGISel::PostprocessISelDAG virtual
method to perform post-selection peephole optimizations on the DAG
representation.
One optimization is implemented here: folds to clean up complex
addressing expressions for thread-local storage and medium code
model. It will also be useful for large code model sequences when
those are added later. I originally thought about doing this on the
MI representation prior to register assignment, but it's difficult to
do effective global dead code elimination at that point. DCE is
trivial on the DAG representation.
A typical example of a candidate code sequence in assembly:
addis 3, 2, globalvar@toc@ha
addi 3, 3, globalvar@toc@l
lwz 5, 0(3)
When the final instruction is a load or store with an immediate offset
of zero, the offset from the add-immediate can replace the zero,
provided the relocation information is carried along:
addis 3, 2, globalvar@toc@ha
lwz 5, globalvar@toc@l(3)
Since the addi can in general have multiple uses, we need to only
delete the instruction when the last use is removed.
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This handles the cases where the 6-bit splat element is odd, converting
to a three-instruction sequence to add or subtract two splats. With this
fix, the XFAIL in test/CodeGen/PowerPC/vec_constants.ll is removed.
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The PPC backend doesn't handle these correctly. This patch uses logic
similar to that in the X86 and ARM backends to track these arguments
properly.
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During lowering of a BUILD_VECTOR, we look for opportunities to use a
vector splat. When the splatted value fits in 5 signed bits, a single
splat does the job. When it doesn't fit in 5 bits but does fit in 6,
and is an even value, we can splat on half the value and add the result
to itself.
This last optimization hasn't been working recently because of improved
constant folding. To circumvent this, create a pseudo VADD_SPLAT that
can be expanded during instruction selection.
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GCC warns about the attribute being ignored if it occurs after void*.
There seems to be some kind of incompatibility between clang and gcc here, but
I can't fathom who's right.
void* LLVM_LIBRARY_VISIBILITY foo(); // clang: hidden, gcc: default
LLVM_LIBRARY_VISIBILITY void *bar(); // clang: hidden, gcc: hidden
void LLVM_LIBRARY_VISIBILITY qux(); // clang: hidden, gcc: hidden
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than we need to and some ELF linkers complain about directly accessing symbols
with default visibility.
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blocks. We still don't have consensus if we should try to change clang or
the standard, but llvm should work with compilers that implement the current
standard and mangle those functions.
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Since functions with internal linkage don't have language linkage, it is valid
to overload them:
extern "C" {
static int foo();
static int foo(int);
}
So we mangle them.
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Thanks to help from Nadav and Hal, I have a more reasonable (and even
correct!) approach. This specifically penalizes the insertelement
and extractelement operations for the performance hit that will occur
on PowerPC processors.
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Certain vector operations don't vectorize well with the current
PowerPC implementation. Element insert/extract performs poorly
without VSX support because Altivec requires going through memory.
SREM, UREM, and VSELECT all produce bad scalar code.
There's a lot of work to do for the cost model before
autovectorization will be tuned well, and this is not an attempt to
address the larger problem.
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Most of PPCCallingConv.td is used only by the 32-bit SVR4 ABI. Rename
things to clarify this. Also delete some code that's been commented out
for a long time.
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The liveout lists are about to be removed from MRI, this is the only
place they were used after register allocation.
Get the live out V registers directly from the return instructions
instead.
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I didn't see those because the test case used "not grep". FileCheck the test and
XFAIL it, preserving the old optimization, so this can be fixed eventually.
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This required disabling a PowerPC optimization that did the following:
input:
x = BUILD_VECTOR <i32 16, i32 16, i32 16, i32 16>
lowered to:
tmp = BUILD_VECTOR <i32 8, i32 8, i32 8, i32 8>
x = ADD tmp, tmp
The add now gets folded immediately and we're back at the BUILD_VECTOR we
started from. I don't see a way to fix this currently so I left it disabled
for now.
Fix some trivially foldable X86 tests too.
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This is the first commit of a large series which will add support for the
QPX vector instruction set to the PowerPC backend. This instruction set is
used on the IBM Blue Gene/Q supercomputers.
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conditions are met:
1. They share the same operand and are in the same BB.
2. Both outputs are used.
3. The target has a native instruction that maps to ISD::FSINCOS node or
the target provides a sincos library call.
Implemented the generic optimization in sdisel and enabled it for
Mac OSX. Also added an additional optimization for x86_64 Mac OSX by
using an alternative entry point __sincos_stret which returns the two
results in xmm0 / xmm1.
rdar://13087969
PR13204
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This provides a place to add customized operation cost information and
control some other target-specific IR-level transformations.
The only non-trivial logic in this checkin assigns a higher cost to
unaligned loads and stores (covered by the included test case).
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No functionality change intended.
This captures the first two cases GPR32/64. For the others, we need
an addition operator (if we have one, I've not yet found it).
Based on a suggestion made by Tom Stellard in the AArch64 review!
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_Complex float and _Complex long double, by simply increasing the
number of floating point registers available for return values.
The test case verifies that the correct registers are loaded.
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This patch adjust the r171506 to make all DWARF enconding pc-relative
for PPC64. It also adds the R_PPC64_REL32 relocation handling in MCJIT
(since the eh_frame will not generate PIC-relative relocation) and also
adds the emission of stubs created by the TTypeEncoding.
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code generation. Variables addressed through a GlobalAlias were not being
handled, and variables with available_externally linkage were treated
incorrectly. The patch contains two new tests to verify the correct code
generation for these cases.
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a TargetMachine to construct (and thus isn't always available), to an
analysis group that supports layered implementations much like
AliasAnalysis does. This is a pretty massive change, with a few parts
that I was unable to easily separate (sorry), so I'll walk through it.
The first step of this conversion was to make TargetTransformInfo an
analysis group, and to sink the nonce implementations in
ScalarTargetTransformInfo and VectorTargetTranformInfo into
a NoTargetTransformInfo pass. This allows other passes to add a hard
requirement on TTI, and assume they will always get at least on
implementation.
The TargetTransformInfo analysis group leverages the delegation chaining
trick that AliasAnalysis uses, where the base class for the analysis
group delegates to the previous analysis *pass*, allowing all but tho
NoFoo analysis passes to only implement the parts of the interfaces they
support. It also introduces a new trick where each pass in the group
retains a pointer to the top-most pass that has been initialized. This
allows passes to implement one API in terms of another API and benefit
when some other pass above them in the stack has more precise results
for the second API.
The second step of this conversion is to create a pass that implements
the TargetTransformInfo analysis using the target-independent
abstractions in the code generator. This replaces the
ScalarTargetTransformImpl and VectorTargetTransformImpl classes in
lib/Target with a single pass in lib/CodeGen called
BasicTargetTransformInfo. This class actually provides most of the TTI
functionality, basing it upon the TargetLowering abstraction and other
information in the target independent code generator.
The third step of the conversion adds support to all TargetMachines to
register custom analysis passes. This allows building those passes with
access to TargetLowering or other target-specific classes, and it also
allows each target to customize the set of analysis passes desired in
the pass manager. The baseline LLVMTargetMachine implements this
interface to add the BasicTTI pass to the pass manager, and all of the
tools that want to support target-aware TTI passes call this routine on
whatever target machine they end up with to add the appropriate passes.
The fourth step of the conversion created target-specific TTI analysis
passes for the X86 and ARM backends. These passes contain the custom
logic that was previously in their extensions of the
ScalarTargetTransformInfo and VectorTargetTransformInfo interfaces.
I separated them into their own file, as now all of the interface bits
are private and they just expose a function to create the pass itself.
Then I extended these target machines to set up a custom set of analysis
passes, first adding BasicTTI as a fallback, and then adding their
customized TTI implementations.
The fourth step required logic that was shared between the target
independent layer and the specific targets to move to a different
interface, as they no longer derive from each other. As a consequence,
a helper functions were added to TargetLowering representing the common
logic needed both in the target implementation and the codegen
implementation of the TTI pass. While technically this is the only
change that could have been committed separately, it would have been
a nightmare to extract.
The final step of the conversion was just to delete all the old
boilerplate. This got rid of the ScalarTargetTransformInfo and
VectorTargetTransformInfo classes, all of the support in all of the
targets for producing instances of them, and all of the support in the
tools for manually constructing a pass based around them.
Now that TTI is a relatively normal analysis group, two things become
straightforward. First, we can sink it into lib/Analysis which is a more
natural layer for it to live. Second, clients of this interface can
depend on it *always* being available which will simplify their code and
behavior. These (and other) simplifications will follow in subsequent
commits, this one is clearly big enough.
Finally, I'm very aware that much of the comments and documentation
needs to be updated. As soon as I had this working, and plausibly well
commented, I wanted to get it committed and in front of the build bots.
I'll be doing a few passes over documentation later if it sticks.
Commits to update DragonEgg and Clang will be made presently.
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This patch fixes the PPC eh_frame definitions for the personality and
frame unwinding for PIC objects. It makes PIC build correctly creates
relative relocations in the '.rela.eh_frame' segments and thus avoiding
a text relocation that generates a DT_TEXTREL segments in link phase.
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into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.
There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.
The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.
I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).
I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.
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directly.
This is in preparation for removing the use of the 'Attribute' class as a
collection of attributes. That will shift to the AttributeSet class instead.
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Use of store or load with the atomic specifier on 64-bit types would
cause instruction-selection failures. As with the 32-bit case, these
can use the default expansion in terms of cmp-and-swap.
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There's probably a better expansion for those nodes than the default for
altivec, but this is better than crashing. VSELECTs occur in loop vectorizer
output.
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for TLS dynamic models on 64-bit PowerPC ELF. The default sort routine
for relocations only sorts on the r_offset field; but with TLS, there
can be two relocations with the same r_offset. For PowerPC, this patch
sorts secondarily on descending r_type, which matches the behavior
expected by the linker.
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for a wider range of GOT entries that can hold thread-relative offsets.
This matches the behavior of GCC, which was not documented in the PPC64 TLS
ABI. The ABI will be updated with the new code sequence.
Former sequence:
ld 9,x@got@tprel(2)
add 9,9,x@tls
New sequence:
addis 9,2,x@got@tprel@ha
ld 9,x@got@tprel@l(9)
add 9,9,x@tls
Note that a linker optimization exists to transform the new sequence into
the shorter sequence when appropriate, by replacing the addis with a nop
and modifying the base register and relocation type of the ld.
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some hackery in place that hid my poor use of TblGen, which I've now sorted
out and cleaned up. No change in observable behavior, so no new test cases.
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PowerPC target. This is the last of the four models, so we now have
full TLS support.
This is mostly a straightforward extension of the general dynamic model.
I had to use an additional Chain operand to tie ADDIS_DTPREL_HA to the
register copy following ADDI_TLSLD_L; otherwise everything above the
ADDIS_DTPREL_HA appeared dead and was removed.
As before, there are new test cases to test the assembly generation, and
the relocations output during integrated assembly. The expected code
gen sequence can be read in test/CodeGen/PowerPC/tls-ld.ll.
There are a couple of things I think can be done more efficiently in the
overall TLS code, so there will likely be a clean-up patch forthcoming;
but for now I want to be sure the functionality is in place.
Bill
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mention the inline memcpy / memset expansion code is a mess?
This patch split the ZeroOrLdSrc argument into two: IsMemset and ZeroMemset.
The first indicates whether it is expanding a memset or a memcpy / memmove.
The later is whether the memset is a memset of zero. It's totally possible
(likely even) that targets may want to do different things for memcpy and
memset of zero.
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Also added more comments to explain why it is generally ok to return true.
- Rename getOptimalMemOpType argument IsZeroVal to ZeroOrLdSrc. It's meant to
be true for loaded source (memcpy) or zero constants (memset). The poor name
choice is probably some kind of legacy issue.
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Given a thread-local symbol x with global-dynamic access, the generated
code to obtain x's address is:
Instruction Relocation Symbol
addis ra,r2,x@got@tlsgd@ha R_PPC64_GOT_TLSGD16_HA x
addi r3,ra,x@got@tlsgd@l R_PPC64_GOT_TLSGD16_L x
bl __tls_get_addr(x@tlsgd) R_PPC64_TLSGD x
R_PPC64_REL24 __tls_get_addr
nop
<use address in r3>
The implementation borrows from the medium code model work for introducing
special forms of ADDIS and ADDI into the DAG representation. This is made
slightly more complicated by having to introduce a call to the external
function __tls_get_addr. Using the full call machinery is overkill and,
more importantly, makes it difficult to add a special relocation. So I've
introduced another opcode GET_TLS_ADDR to represent the function call, and
surrounded it with register copies to set up the parameter and return value.
Most of the code is pretty straightforward. I ran into one peculiarity
when I introduced a new PPC opcode BL8_NOP_ELF_TLSGD, which is just like
BL8_NOP_ELF except that it takes another parameter to represent the symbol
("x" above) that requires a relocation on the call. Something in the
TblGen machinery causes BL8_NOP_ELF and BL8_NOP_ELF_TLSGD to be treated
identically during the emit phase, so this second operand was never
visited to generate relocations. This is the reason for the slightly
messy workaround in PPCMCCodeEmitter.cpp:getDirectBrEncoding().
Two new tests are included to demonstrate correct external assembly and
correct generation of relocations using the integrated assembler.
Comments welcome!
Thanks,
Bill
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on 64-bit PowerPC ELF.
The patch includes code to handle external assembly and MC output with the
integrated assembler. It intentionally does not support the "old" JIT.
For the initial-exec TLS model, the ABI requires the following to calculate
the address of external thread-local variable x:
Code sequence Relocation Symbol
ld 9,x@got@tprel(2) R_PPC64_GOT_TPREL16_DS x
add 9,9,x@tls R_PPC64_TLS x
The register 9 is arbitrary here. The linker will replace x@got@tprel
with the offset relative to the thread pointer to the generated GOT
entry for symbol x. It will replace x@tls with the thread-pointer
register (13).
The two test cases verify correct assembly output and relocation output
as just described.
PowerPC-specific selection node variants are added for the two
instructions above: LD_GOT_TPREL and ADD_TLS. These are inserted
when an initial-exec global variable is encountered by
PPCTargetLowering::LowerGlobalTLSAddress(), and later lowered to
machine instructions LDgotTPREL and ADD8TLS. LDgotTPREL is a pseudo
that uses the same LDrs support added for medium code model's LDtocL,
with a different relocation type.
The rest of the processing is straightforward.
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missed in the first pass because the script didn't yet handle include
guards.
Note that the script is now able to handle all of these headers without
manual edits. =]
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Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.
Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]
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instruction (vmaddfp) to conform with IEEE to ensure the sign of a zero
result when resulting product is -0.0.
The -0.0 vector addend to vmaddfp is generated by a creating a vector
with full bits sets and then shifting each elements by 31-bits to the
left, resulting in a vector of 0x80000000 (or -0.0 as float).
The 'buildvec_canonicalize.ll' was adjusted to reflect this change and
the 'vec_mul.ll' was complemented with the float vector multiplication
test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168998 91177308-0d34-0410-b5e6-96231b3b80d8
The createPPCMCAsmInfo routine used PPC::R1 as the initial frame
pointer register, but on PPC64 the 32-bit R1 register does not
have a corresponding DWARF number, causing invalid CIE initial
frame state to be emitted. Fix by using PPC::X1 instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168799 91177308-0d34-0410-b5e6-96231b3b80d8
When the CodeGenInfo is to be created for the PPC64 target machine,
a default code-model selection is converted to CodeModel::Medium
provided we are not targeting the Darwin OS. Defaults for Darwin
are unaffected.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168747 91177308-0d34-0410-b5e6-96231b3b80d8
The default for 64-bit PowerPC is small code model, in which TOC entries
must be addressable using a 16-bit offset from the TOC pointer. Additionally,
only TOC entries are addressed via the TOC pointer.
With medium code model, TOC entries and data sections can all be addressed
via the TOC pointer using a 32-bit offset. Cooperation with the linker
allows 16-bit offsets to be used when these are sufficient, reducing the
number of extra instructions that need to be executed. Medium code model
also does not generate explicit TOC entries in ".section toc" for variables
that are wholly internal to the compilation unit.
Consider a load of an external 4-byte integer. With small code model, the
compiler generates:
ld 3, .LC1@toc(2)
lwz 4, 0(3)
.section .toc,"aw",@progbits
.LC1:
.tc ei[TC],ei
With medium model, it instead generates:
addis 3, 2, .LC1@toc@ha
ld 3, .LC1@toc@l(3)
lwz 4, 0(3)
.section .toc,"aw",@progbits
.LC1:
.tc ei[TC],ei
Here .LC1@toc@ha is a relocation requesting the upper 16 bits of the
32-bit offset of ei's TOC entry from the TOC base pointer. Similarly,
.LC1@toc@l is a relocation requesting the lower 16 bits. Note that if
the linker determines that ei's TOC entry is within a 16-bit offset of
the TOC base pointer, it will replace the "addis" with a "nop", and
replace the "ld" with the identical "ld" instruction from the small
code model example.
Consider next a load of a function-scope static integer. For small code
model, the compiler generates:
ld 3, .LC1@toc(2)
lwz 4, 0(3)
.section .toc,"aw",@progbits
.LC1:
.tc test_fn_static.si[TC],test_fn_static.si
.type test_fn_static.si,@object
.local test_fn_static.si
.comm test_fn_static.si,4,4
For medium code model, the compiler generates:
addis 3, 2, test_fn_static.si@toc@ha
addi 3, 3, test_fn_static.si@toc@l
lwz 4, 0(3)
.type test_fn_static.si,@object
.local test_fn_static.si
.comm test_fn_static.si,4,4
Again, the linker may replace the "addis" with a "nop", calculating only
a 16-bit offset when this is sufficient.
Note that it would be more efficient for the compiler to generate:
addis 3, 2, test_fn_static.si@toc@ha
lwz 4, test_fn_static.si@toc@l(3)
The current patch does not perform this optimization yet. This will be
addressed as a peephole optimization in a later patch.
For the moment, the default code model for 64-bit PowerPC will remain the
small code model. We plan to eventually change the default to medium code
model, which matches current upstream GCC behavior. Note that the different
code models are ABI-compatible, so code compiled with different models will
be linked and execute correctly.
I've tested the regression suite and the application/benchmark test suite in
two ways: Once with the patch as submitted here, and once with additional
logic to force medium code model as the default. The tests all compile
cleanly, with one exception. The mandel-2 application test fails due to an
unrelated ABI compatibility with passing complex numbers. It just so happens
that small code model was incredibly lucky, in that temporary values in
floating-point registers held the expected values needed by the external
library routine that was called incorrectly. My current thought is to correct
the ABI problems with _Complex before making medium code model the default,
to avoid introducing this "regression."
Here are a few comments on how the patch works, since the selection code
can be difficult to follow:
The existing logic for small code model defines three pseudo-instructions:
LDtoc for most uses, LDtocJTI for jump table addresses, and LDtocCPT for
constant pool addresses. These are expanded by SelectCodeCommon(). The
pseudo-instruction approach doesn't work for medium code model, because
we need to generate two instructions when we match the same pattern.
Instead, new logic in PPCDAGToDAGISel::Select() intercepts the TOC_ENTRY
node for medium code model, and generates an ADDIStocHA followed by either
a LDtocL or an ADDItocL. These new node types correspond naturally to
the sequences described above.
The addis/ld sequence is generated for the following cases:
* Jump table addresses
* Function addresses
* External global variables
* Tentative definitions of global variables (common linkage)
The addis/addi sequence is generated for the following cases:
* Constant pool entries
* File-scope static global variables
* Function-scope static variables
Expanding to the two-instruction sequences at select time exposes the
instructions to subsequent optimization, particularly scheduling.
The rest of the processing occurs at assembly time, in
PPCAsmPrinter::EmitInstruction. Each of the instructions is converted to
a "real" PowerPC instruction. When a TOC entry needs to be created, this
is done here in the same manner as for the existing LDtoc, LDtocJTI, and
LDtocCPT pseudo-instructions (I factored out a new routine to handle this).
I had originally thought that if a TOC entry was needed for LDtocL or
ADDItocL, it would already have been generated for the previous ADDIStocHA.
However, at higher optimization levels, the ADDIStocHA may appear in a
different block, which may be assembled textually following the block
containing the LDtocL or ADDItocL. So it is necessary to include the
possibility of creating a new TOC entry for those two instructions.
Note that for LDtocL, we generate a new form of LD called LDrs. This
allows specifying the @toc@l relocation for the offset field of the LD
instruction (i.e., the offset is replaced by a SymbolLo relocation).
When the peephole optimization described above is added, we will need
to do similar things for all immediate-form load and store operations.
The seven "mcm-n.ll" test cases are kept separate because otherwise the
intermingling of various TOC entries and so forth makes the tests fragile
and hard to understand.
The above assumes use of an external assembler. For use of the
integrated assembler, new relocations are added and used by
PPCELFObjectWriter. Testing is done with "mcm-obj.ll", which tests for
proper generation of the various relocations for the same sequences
tested with the external assembler.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168708 91177308-0d34-0410-b5e6-96231b3b80d8
The last remaining bit is "bcl 20, 31, AnonSymbol", which I couldn't find the
instruction definition for. Only whitespace changes in assembly output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168541 91177308-0d34-0410-b5e6-96231b3b80d8
This patch lowers the llvm.floor, llvm.ceil, llvm.trunc, and
llvm.nearbyint to Altivec instruction when using 4 single-precision
float vectors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168086 91177308-0d34-0410-b5e6-96231b3b80d8