Summary:
Currently, MachineVerifier will attempt to verify that tied operands
satisfy register constraints as soon as the function is no longer in
SSA form. However, PHIElimination will take the function out of SSA
form while TwoAddressInstructionPass will actually rewrite tied operands
to match the constraints. PHIElimination runs first in the pipeline.
Therefore, whenever the MachineVerifier is run after PHIElimination,
it will encounter verification errors on any tied operands.
This patch adds a function property called TiedOpsRewritten that will be
set by TwoAddressInstructionPass and will control when the verifier checks
tied operands.
Reviewed By: nemanjai
Differential Revision: https://reviews.llvm.org/D80538
The previous implementation used "asm parser only" pseudo-instructions in their
output patterns. Those are not meant to emit code and will caused crashes when
built with -filetype=obj.
Differential Revision: https://reviews.llvm.org/D80151
The function emitRLDICWhenLoweringJumpTables in PPCMIPeephole.cpp
was supposed to convert a pair of RLDICL and RLDICR to a single RLDIC,
but it was leaving out the RLDICL instruction. This PR fixes the bug.
Differential Revision: https://reviews.llvm.org/D78063
If there are more than 65534 relocation entries in a single section,
we should generate an overflow section.
Since we don't support overflow section for now, we should generate
an error.
Differential revision: https://reviews.llvm.org/D81104
After pseudo-expansion, we may end up with ADDI (add immediate)
instructions where the operand is not an immediate but a relocation.
For such instructions, attempts to get the immediate result in
assertion failures for obvious reasons.
Fixes: https://bugs.llvm.org/show_bug.cgi?id=45432
The instruction addi is usually used to post increase the loop indvar, which looks like this:
label_X:
load x, base(i)
...
y = op x
...
i = addi i, 1
goto label_X
However, for PowerPC, if there are too many vsx instructions that between y = op x and i = addi i, 1,
it will use all the hw resource that block the execution of i = addi, i, 1, which result in the stall
of the load instruction in next iteration. So, a heuristic is added to move the addi as early as possible
to have the load hide the latency of vsx instructions, if other heuristic didn't apply to avoid the starve.
Reviewed By: jji
Differential Revision: https://reviews.llvm.org/D80269
Calls that are marked as @notoc do not require the extra nop after the call
for the TOC restore.
Differential Revision: https://reviews.llvm.org/D81081
Summary: A bug is reported in bugzilla-45628, where the swap_with_shift case can’t be matched to a single HW instruction xxswapd as expected. In fact the case matches the idiom of rotate, but PPC doesn’t support ROTL v1i128.
This is a NFC patch for testing ROTL with v1i128 at master.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D81073
On PowerPC, FNMSUB (both VSX and non-VSX version) means -(a*b-c). But
the backend used to generate these instructions regardless whether nsz
flag exists or not. If a*b-c==0, such transformation changes sign of
zero.
This patch introduces PPC specific FNMSUB ISD opcode, which may help
improving combined FMA code sequence.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D76585
Record internal state based on register units. This is often more
efficient as there are typically fewer register units to update
compared to iterating over all the aliases of a register.
Original patch by Matthias Braun, but I've been rebasing and fixing it
for almost 2 years and fixed a few bugs causing intermediate failures
to make this patch independent of the changes in
https://reviews.llvm.org/D52010.
Without this change, names start with 'L' will get created as
temporary symbol in MCContext::createSymbol.
Some other potential prefix considered:
.L, does not work for AIX, as a function start with L will end
up with .L as prefix for its function entry point.
..L could work, but it does not play well with the convention
on AIX that anything start with '.' are considered as entry point.
L. could work, but not sure if it's safe enough, as it's possible
to have suffixes like .something append to a plain L, giving L.something
which is not necessarily a temporary.
That's why we picked L.. for now.
Differential Revision: https://reviews.llvm.org/D80831
In the function "Analysis.cpp:isInTailCallPosition", it only checks whether
a call is in a tail call position if the call has side effects, access memory
or it is not safe to speculative execute. Therefore, a speculatable function
will not go through tail call position check and improperly tail called when
it is not in a tail-call position. This patch enables tail call position check
for speculatable functions.
Differential Revision: https://reviews.llvm.org/D80661
Summary:
The standard data emission directives (e.g. .short, .long) in the AIX assembler
have the unintended consequence of aligning their output to the natural byte
boundary. This cause problems because we aren't expecting behavior from the
Data*bitsDirectives, so the final alignment of data isn't correct in some cases
on AIX.
This patch updated the Data*bitsDirectives to use .vbyte pseudo-ops instead to emit the
data, since we will emit the .align directives as needed. We update the existing
testcases and add a test for emission of struct data.
Reviewers: hubert.reinterpretcast, Xiangling_L, jasonliu
Reviewed By: hubert.reinterpretcast, jasonliu
Subscribers: wuzish, nemanjai, hiraditya, kbarton, arphaman, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D80934
This patch implements a target independent DAG combine to produce multiply-high
instructions from shifts. This DAG combine will combine shifts for any type as
long as the MULH on the narrow type is legal.
For now, it is enabled on PowerPC as PowerPC is the only target that has an
implementation of the isMulhCheaperThanMulShift TLI hook introduced in
D78271.
Moreover, this DAG combine focuses on catching the pattern:
(shift (mul (ext <narrow_type>:$a to <wide_type>), (ext <narrow_type>:$b to <wide_type>)), <narrow_width>)
to produce mulhs when we have a sign-extend, and mulhu when we have
a zero-extend.
The patch performs the following checks:
- Operation is a right shift arithmetic (sra) or logical (srl)
- Input to the shift is a multiply
- Both operands to the shift are sext/zext nodes
- The extends into the multiply are both the same
- The narrow type is half the width of the wide type
- The shift amount is the width of the narrow type
- The respective mulh operation is legal
Differential Revision: https://reviews.llvm.org/D78272
Summary: Exploit vabsd* for for absolute difference of vectors on P9,
for example:
void foo (char *restrict p, char *restrict q, char *restrict t)
{
for (int i = 0; i < 16; i++)
t[i] = abs (p[i] - q[i]);
}
this case should be matched to the HW instruction vabsdub.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D80271
Let the codegen recognized the nomerge attribute and disable branch folding when the attribute is given
Differential Revision: https://reviews.llvm.org/D79537
Since on AIX, our strategy is to not use -u to suppress any undefined
symbols, we need to emit .extern for the symbols with AvailableExternally
linkage.
Differential Revision: https://reviews.llvm.org/D80642
Summary:
This patch simply adds support for the new CPU in anticipation of
Power10. There isn't really any functionality added so there are no
associated test cases at this time.
Reviewers: stefanp, nemanjai, amyk, hfinkel, power-llvm-team, #powerpc
Reviewed By: stefanp, nemanjai, amyk, #powerpc
Subscribers: NeHuang, steven.zhang, hiraditya, llvm-commits, wuzish, shchenz, cfe-commits, kbarton, echristo
Tags: #clang, #powerpc, #llvm
Differential Revision: https://reviews.llvm.org/D80020
Summary:
This patch simply adds support for the new CPU in anticipation of
Power10. There isn't really any functionality added so there are no
associated test cases at this time.
Reviewers: stefanp, nemanjai, amyk, hfinkel, power-llvm-team, #powerpc
Reviewed By: stefanp, nemanjai, amyk, #powerpc
Subscribers: NeHuang, steven.zhang, hiraditya, llvm-commits, wuzish, shchenz, cfe-commits, kbarton, echristo
Tags: #clang, #powerpc, #llvm
Differential Revision: https://reviews.llvm.org/D80020
The test case provided in PR45709 can be simplified by DCE to an
empty function. To prevent this from happening if DCE is run prior
to ISEL in the back end, just add optnone to the function. The
behaviour it is testing for is in the SDAG legalization and is
not sensitive to optnone so the test case still achieves its desired
objective.
As reported in PR45186, we could be in a situation where we don't
want to handle unaligned memory accesses for FP scalars but still
have VSX (which allows unaligned access for vectors). Change the
default to only apply to scalars.
Fixes: https://bugs.llvm.org/show_bug.cgi?id=45186
As reported in https://bugs.llvm.org/show_bug.cgi?id=45709 we can hit an
infinite loop in legalization since we set the legalization action for
ISD::SELECT_CC for all fixed length vector types to Promote. Without some
different legalization action for the type being promoted to, the legalizer
simply loops. Since we don't have patterns to match the node, the right
legalization action should be Expand.
Differential revision: https://reviews.llvm.org/D79854
This patch introduces a TargetLowering query, isMulhCheaperThanMulShift.
Currently in DAG Combine, it will transform mulhs/mulhu into a
wider multiply and a shift if the wide multiply is legal.
This TLI function is implemented on 64-bit PowerPC, as it is more desirable to
have multiply-high over multiply + shift for words and doublewords. Having
multiply-high can also aid in further transformations that can be done.
Differential Revision: https://reviews.llvm.org/D78271
To be consistent with other directives like '.comm', '.lcomm', we remove
the spaces after the comma for '.csect' on AIX.
Differential Revision: https://reviews.llvm.org/D80247
The fix for PR39865 took care of some of the handling for half precision
but it missed a number of issues that still exist. This patch fixes the
remaining issues that cause crashes in the PPC back end.
Fixes: https://bugs.llvm.org/show_bug.cgi?id=45776
Differential revision: https://reviews.llvm.org/D79283
Summary: This patch adds the intrinsic llvm.ppc.popcntb for the HW
instruction POPCNTB
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D79703
SplitCSR was only suppored for functions with CXX_FAST_TLS calling
convention. Clang only emits that calling convention for Darwin which is
no longer supported by the PowerPC backend. Another IR producer could
use the calling convention, but considering the calling convention is
meant to be an optimization and the codegen for SplitCSR can be
attrocious on Power (see the modifed lit test) it is best to remove it
and codegen CXX_FAST_TLS same as the C calling convention.
Differential Revision: https://reviews.llvm.org/D79018
A lot of tests under PowerPC are using fast flag, while fast is just
alias of 7 fast-math flags. This change makes test points clearer.
mc-instrlat.ll and sms-iterator.ll keeps unchanged since they are not
testing fast-math behavior. (one for machine combiner crash, one for
machine pipeliner bug)
Reviewed By: steven.zhang, spatel
Differential Revision: https://reviews.llvm.org/D78989
xsnegdp, xsabsdp and xsnabsdp can be used to operate on f32 operand.
This patch adds the missing patterns since we prefer VSX instructions
when available.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D75344
Legalizer should respect both command-line options or SDNode-level
fast-math flags.
Also, this patch propagates other flags during custom simplifying.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D79074
Summary:
The ppc-early-ret pass use the addReg() to add operand to the new
instruction, it can't reserve the flag of old operand. This has caused
machine verfications failed.
This patch use add() to instead of addReg().
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D77997
Summary:
The SPE doesn't have a 'fma' instruction, so the intrinsic becomes a
libcall. It really should become an expansion to two instructions, but
for some reason the compiler doesn't think that's as optimal as a
branch. Since this lowering is done after CTR is allocated for loops,
tell the optimizer that CTR may be used in this case. This prevents a
"Invalid PPC CTR loop!" assertion in the case that a fma() function call
is used in a C/C++ file, and clang converts it into an intrinsic.
Reviewed By: shchenz
Differential Revision: https://reviews.llvm.org/D78668
This patch folds redundant load immediates into a zero for instructions
which recognise this as the value zero and not the register. If the load
immediate is no longer in use it is then deleted.
This is already done in earlier passes but the ppc-mi-peephole allows for
a more general implementation.
Differential Revision: https://reviews.llvm.org/D69168
This patch adds strict-fp intrinsics support for fma, fsqrt, fmaxnum and
fminnum on PowerPC.
Reviewed By: hfinkel
Differential Revision: https://reviews.llvm.org/D72749
Summary:
This patch tries to emit the correct alignment result for both
object file generation path and assembly path.
Reviewed by: hubert.reinterpretcast, DiggerLin, daltenty
Differential Revision: https://reviews.llvm.org/D79127
Summary:
This patch will set the variable PredictableSelectIsExpensive to do the
select to if based on BranchProbability in CodeGenPrepare.
When the BranchProbability more than MinPercentageForPredictableBranch,
PPC will convert SELECT to branch.
Reviewed By: nemanjai
Differential Revision: https://reviews.llvm.org/D71883
The code to prevent using `PPCXCOFFMCAsmInfo` with little-endian targets
used an incorrect check. Also, there does not appear to be sufficient
earlier checking to prevent failing this check, so the check here is
upgraded to be a `report_fatal_error`.
`PPCAIXAsmPrinter` was also missing a check against use with
little-endian targets. This patch adds such a check in.
Summary:
`AsmPrinter::emitGlobalIndirectSymbol` is dependent on
`MCStreamer::emitAssignment` to produce `.set` directives for alias
symbols; however, the `.set` pseudo-op on AIX is documented as not
usable with external relocatable terms or expressions, which limits its
applicability in generating alias symbols.
Disable generating aliases on AIX until a different implementation
strategy is available.
Reviewers: cebowleratibm, jasonliu, sfertile, daltenty, DiggerLin
Reviewed By: jasonliu
Differential Revision: https://reviews.llvm.org/D79044
This patch adds ORE for MachinePipeliner, so that people can anaylyze
their code using opt-viewer or other tools, then optimize the code to
catch more piplining opportunities.
Reviewed By: bcahoon
Differential Revision: https://reviews.llvm.org/D79368
Call getNegatedExpression(Cost) and check the Cost to make the code more clear.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D78347
Implement passing of ByVal formal arguments when the argument is passed
partly in the argument registers, with the remainder of the argument
passed on the stack.
Differential Revision: https://reviews.llvm.org/D78515
getTargetStreamer() might return null (e.g. when running inlined-strings.ll test),
downcasting to a reference will be wrong. This is detectable with -fsanitize=null.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D78686
Currently, on PowerPC target, it uses function scope UnsafeFPMath
option to drive Machine Combiner pass.
This is not accurate in two ways:
1: the scope is not accurate. Machine Combiner pass only requires
instruction-level flags instead of the function scope.
2: the float point flag is not accurate. Machine Combiner pass
only requires float point flags reassoc and nsz.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D78183
Summary:
In the ppc-expand-isel pass, we use stepForward() to update the
liveins, this function is not recommended, because it needs the
accurate kill info.
This patch uses the function computeAndAddLiveIns() to update the
liveins, it's the recommended method and can fix the liveins bug for
ppc-expand-isel pass..
Reviewed By: efriedma, lkail
Differential Revision: https://reviews.llvm.org/D78657
The code assumed that zero-extending the integer constant to the
designated alloc size would be fine even for BE targets, but that's not
the case as that pulls in zeros from the MSB side while we actually
expect the padding zeros to go after the LSB.
I've changed the codepath handling the constant integers to use the
store size for both small(er than u64) and big constants and then add
zero padding right after that.
Differential Revision: https://reviews.llvm.org/D78011
Tail Calls were initially disabled for PC Relative code because it was not safe
to make certain assumptions about the tail calls (namely that all compiled
functions no longer used the TOC pointer in R2). However, once all of the
TOC pointer references have been removed it is safe to tail call everything
that was tail called prior to the PC relative additions as well as a number of
new cases.
For example, it is now possible to tail call indirect functions as there is no
need to save and restore the TOC pointer for indirect functions if the caller
is marked as may clobber R2 (st_other=1). For the same reason it is now also
possible to tail call functions that are external.
Differential Revision: https://reviews.llvm.org/D77788
Follow-up of D78082 and D78590.
Otherwise, because xray_instr_map is now read-only, the absolute
relocation used for Sled.Function will cause a text relocation.
Follow-up of D78082 (x86-64).
This change avoids dynamic relocations in `xray_instr_map` for ARM/AArch64/powerpc64le.
MIPS64 cannot use 64-bit PC-relative addresses because R_MIPS_PC64 is not defined.
Because MIPS32 shares the same code, for simplicity, we don't use PC-relative addresses for MIPS32 as well.
Tested on AArch64 Linux and ppc64le Linux.
Reviewed By: ianlevesque
Differential Revision: https://reviews.llvm.org/D78590
Currently an indirect call produces the following sequence on PCRelative mode:
extern void function( );
extern void (*ptrfunc) ( );
void g() {
ptrfunc=function;
}
void f() {
(*ptrfunc) ( );
}
Producing
paddi 3, 0, .LC0@PCREL, 1
ld 3, 0(3)
std 2, 24(1)
ld 12, 0(3)
mtctr 12
bctrl
ld 2, 24(1)
Though the caller does not use or preserve r2, it is still saved and restored
across a function call. This patch is added to remove these redundant save and
restores for indirect calls.
Differential Revision: https://reviews.llvm.org/D77749
Add initial support for PC Relative addressing to get jump table base
address instead of using TOC.
Differential Revision: https://reviews.llvm.org/D75931
This patch exploits rldimi instruction for patterns like
`or %a, 0b000011110000`, which saves number of instructions when the
operand has only one use, compared with `li-ori-sldi-or`.
Reviewed By: nemanjai
Differential Revision: https://reviews.llvm.org/D77850
This is an optimization that applies to global addresses and
allows for the following transformation:
Convert this:
paddi r3, 0, symbol@PCREL, 1
ld r4, 8(r3)
To this:
pld r4, symbol@PCREL+8(0), 1
An instruction is saved and the linker can do the addition when
the symbol is resolved.
Differential Revision: https://reviews.llvm.org/D76160
Adds support for passing a ByVal formal argument completely on the stack
(ie after all argument registers are exhausted).
Differential Revision: https://reviews.llvm.org/D78263
Summary:
The patch D29014 has added the new ISD::FREEZE and can deal with the
integer.
The patch D76980 has added SoftenFloatRes_FREEZE for float point.
But we still lack of expand for ppc_fp128, this will cause assertion for
some cases.
This patch is to support freeze expand for ppc_fp128.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D78278
Add initial support for PC Relative addressing for global values that
require GOT indirect addressing. This patch adds PCRelative support for
global addresses that may not be known at link time and may require
access through the GOT.
Differential Revision: https://reviews.llvm.org/D76064
Summary:
AIX symbol have qualname and unqualified name. The stock getSymbol
could only return unqualified name, which leads us to patch many
caller side(lowerConstant, getMCSymbolForTOCPseudoMO).
So we should try to address this problem in the callee
side(getSymbol) and clean up the caller side instead.
Note: this is a "mostly" NFC patch, with a fix for the original
lowerConstant behavior.
Differential Revision: https://reviews.llvm.org/D78045
If we are and the constant like 0xFFFFFFC00000, for now, we are using several
instructions to generate this 48bit constant and final an "and". However, we
could exploit it with two rotate instructions.
MB ME MB+63-ME
+----------------------+ +----------------------+
|0000001111111111111000| -> |0000000001111111111111|
+----------------------+ +----------------------+
0 63 0 63
Rotate left ME + 1 bit first, and then, mask it with (MB + 63 - ME, 63),
finally, rotate back. Notice that, we need to round it with 64 bit for the
wrapping case.
Reviewed by: ChenZheng, Nemanjai
Differential Revision: https://reviews.llvm.org/D71831
This patch adds PC Relative support for global values that are known at link
time. If a global value requires access through the global offset table (GOT)
it is not covered in this patch.
Differential Revision: https://reviews.llvm.org/D75280
Summary:
When doing the conversion: MachineInst -> MCInst, we should ignore the
implicit operands, it will expose more opportunity for InstiAlias.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D77118
The "Align" passed into getMachineMemOperand etc. is the alignment of
the MachinePointerInfo, not the alignment of the memory operation.
(getAlign() on a MachineMemOperand automatically reduces the alignment
to account for this.)
We were passing on wrong (overconservative) alignment in a bunch of
places. Fix a bunch of these, mostly in legalization. And while I'm
here, switch to the new Align APIs.
The test changes are all scheduling changes: the biggest effect of
preserving large alignments is that it improves alias analysis, so the
scheduler has more freedom.
(I was originally just trying to do a minor cleanup in
SelectionDAGBuilder, but I accidentally went deeper down the rabbit
hole.)
Differential Revision: https://reviews.llvm.org/D77687
This patch intends to provide relocation support for the expression
contains two unpaired relocatable terms with opposite signs.
Differential Revision: https://reviews.llvm.org/D77424
Previously, getWithOffset() would drop the offset if the base was null.
Because of this, MachineMemOperand would return the wrong result from
getAlign() in these cases. MachineMemOperand stores the alignment of
the pointer without the offset.
A bunch of MIR tests changed because we print the offset now.
Split off from D77687.
Differential Revision: https://reviews.llvm.org/D78049
There was another issue introduced by this commit that the OP
initially missed. Namely, for functions that are free to use
R2 as a callee-saved register, we emit a TOC expression based
on the address of the GEP label without emitting the GEP label.
Since we only emit such expressions for the large code model, this
issue only surfaced there.
I have confirmed that with this fix, the kernel build is successful
with target "all".
Summary:
The patch D63957 is to avoid empty string when scrubbing loop comments,
it will replace loop comments to a `#`, that's correct.
But if the line has something else not only loop comments, we will get
a extra `#`.
The patch is to remove the extra `#`.
Reviewed By: jsji
Differential Revision: https://reviews.llvm.org/D77357
In LowerFP_TO_INTForReuse, when emitting `stfiwx`, alignment of 4 is
set for the `MachineMemOperand`, but RLI(ReuseLoadInfo)'s alignment is
not updated for following loads.
It's related to failed alignment check reported in
https://bugs.llvm.org/show_bug.cgi?id=45297
Differential Revision: https://reviews.llvm.org/D77624
The transformation currently does not differentiate between explicit
and implicit kills. However, it is not valid to later simply clear
an implicit kill flag since the kill could be due to a call or return.
Fixes: https://bugs.llvm.org/show_bug.cgi?id=45374
When we try to select a SELECT_CC on Power9, we check if it can be matched to a
SETB instruction. In that function, we assert that the output type is i32/i64.
This is unnecessary as it is perfectly reasonable to have an i1 SELECT_CC.
Change that from an assert to an early exit condition.
Fixes: https://bugs.llvm.org/show_bug.cgi?id=45448
Summary:
This patch adds support for handling of variadic functions for AIX.
This includes ensuring that use and consume correct type of
va_list (char *va_list) for AIX.
Authored by: ZarkoCA
Reviewers: cebowleratibm, sfertile, jasonliu
Reviewed by: jasonliu
Differential Revision: https://reviews.llvm.org/D76130
Add initial support for PC Relative addressing for constant pool loads.
This includes adding a new relocation for @pcrel and adding a new PowerPC flag
to identify PC relative addressing.
Differential Revision: https://reviews.llvm.org/D74486
Use utils/update_llc_test_checks.py to add full CHECK directives to the
test for cxx_fast_tls calling convention. The calling convention is
arguably dead on PowerPC since dropping Darwin subtarget support in the PowerPC
backend. This test change helps show the atrocious code generation for
this lit test which was hidden by having few CHECK directives.
Any or all the argument registers can be used to pass a byval formal
argument, with the limitation that the argument must fit in the
available registers (ie: is not split between registers and stack).
Differential Revision: https://reviews.llvm.org/D76902
On PowerPC most functions require a valid TOC pointer.
This is the case because either the function itself needs to use this
pointer to access the TOC or because other functions that are called
from that function expect a valid TOC pointer in the register R2.
The main exception to this is leaf functions that do not access the TOC
since they are guaranteed not to need a valid TOC pointer.
This patch introduces a feature that will allow more functions to not
require a valid TOC pointer in R2.
Differential Revision: https://reviews.llvm.org/D73664
There are a few patterns where we use a superclass for inputs to this
instruction rather than the correct class. This can sometimes lead to
unncessary copies.
Summary:
- Remove the no longer used Darwin CalleeSavedRegs
- Combine the SVR464 callee saved regs and AIX64 since the two are (and should be) identical into PPC64
- Update tests for 64-bit CSR change
Reviewers: sfertile, ZarkoCA, cebowleratibm, jasonliu, #powerpc
Reviewed By: sfertile
Subscribers: wuzish, nemanjai, hiraditya, kbarton, shchenz, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D77235
MI peephole will remove unnecessary FRSP instructions. This patch
removes such unnecessary XSRSP.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D77208
Currently, DAG combiner uses (fmul (rsqrt x) x) to estimate square
root of x. However, this method would return NaN if x is +Inf, which
is incorrect.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D76853
Summary:
In https://bugs.llvm.org/show_bug.cgi?id=45297, it fails selecting
instructions for `PPCISD::ST_VSR_SCAL_INT`. The reason it generate the
`PPCISD::ST_VSR_SCAL_INT` with `-power8-vector` in IR is PPC's
combiner checks `hasP8Altivec` rather than `hasP8Vector`. This patch
should resolve PR45297.
Differential Revision: https://reviews.llvm.org/D76773
Summary:
When we encounter an XCOFF file, reflect that in the triple information.
In addition to knowing the object file format, we know that the
associated OS is AIX.
This means that we can expect that there is no output difference in the
processing of an XCOFF32 input file between cases where the triple is
left unspecified by the user and cases where the user specifies
`--triple powerpc-ibm-aix` explicitly.
Reviewers: jhenderson, sfertile, jasonliu, daltenty
Reviewed By: jasonliu
Subscribers: wuzish, nemanjai, hiraditya, MaskRay, rupprecht, steven.zhang, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D77025
This change implements constant folding to constrained versions of
intrinsics, implementing rounding: floor, ceil, trunc, round, rint and
nearbyint.
Differential Revision: https://reviews.llvm.org/D72930
Summary:
Implement several XCOFF hooks to get '-r' option working for llvm-objdump -r.
Reviewer: DiggerLin, hubert.reinterpretcast, jhenderson, MaskRay
Differential Revision: https://reviews.llvm.org/D75131
SUMMARY:
SUMMARY
for a source file "test.c"
void foo() {};
llc will generate assembly code as (assembly patch)
.globl foo
.globl .foo
.csect foo[DS]
foo:
.long .foo
.long TOC[TC0]
.long 0
and symbol table as (xcoff object file)
[4] m 0x00000004 .data 1 unamex foo
[5] a4 0x0000000c 0 0 SD DS 0 0
[6] m 0x00000004 .data 1 extern foo
[7] a4 0x00000004 0 0 LD DS 0 0
After first patch, the assembly will be as
.globl foo[DS] # -- Begin function foo
.globl .foo
.align 2
.csect foo[DS]
.long .foo
.long TOC[TC0]
.long 0
and symbol table will as
[6] m 0x00000004 .data 1 extern foo
[7] a4 0x00000004 0 0 DS DS 0 0
Change the code for the assembly path and xcoff objectfile patch for llc.
Reviewers: Jason Liu
Subscribers: wuzish, nemanjai, hiraditya
Differential Revision: https://reviews.llvm.org/D76162
Summary:
The linker is free to relax this (relocation R_PPC_GOT_TPREL16) against
R_PPC_TLS, if it sees fit (initial exec to local exec). If r0 is used,
this can generate execution-invalid code (converts to 'addi %rX, %r0,
FOO, which translates in PPC-lingo to li %rX, FOO). Forbid this
instead.
This fixes static binaries using locales on FreeBSD/powerpc
(tested on FreeBSD/powerpcspe).
Reviewed By: nemanjai
Differential Revision: https://reviews.llvm.org/D76662
```
// llvm-objdump -d output (before)
0: bl .-4
4: bl .+0
8: bl .+4
// llvm-objdump -d output (after) ; GNU objdump -d
0: bl 0xfffffffc / bl 0xfffffffffffffffc
4: bl 0x4
8: bl 0xc
```
Many Operand's are not annotated as OPERAND_PCREL.
They are not affected (e.g. `b .+67108860`). I plan to fix them in future patches.
Modified test/tools/llvm-objdump/ELF/PowerPC/branch-offset.s to test
address space wraparound for powerpc32 and powerpc64.
Reviewed By: sfertile, jhenderson
Differential Revision: https://reviews.llvm.org/D76591
We can legalize the operation MUL for v8i16 with instruction (vmladduhm A, B, 0)
if altivec enabled. Now, it is set as custom and expand it later, which is not
the right way. And then, we can add the pattern to match the mul + add with (vmladduhm A, B, C)
Reviewed By: Nemanjai
Differential Revision: https://reviews.llvm.org/D76751
An analysis of real world code turned up a number of patterns with BUILD_VECTOR
of nodes resulting from operations on extracted vector elements for which we
produce poor code. This addresses those cases. No attempt is made for
completeness as that would entail a large amount of work for something that
there is no evidence of in real code.
Differential revision: https://reviews.llvm.org/D72660
The e500 core has a silicon bug that triggers an illegal instruction
program trap on any sync other than msync. Other cores will typically
ignore illegal sync types, and the documentation even implies that the
'illegal' bits are ignored.
Address this hardware deficiency by only using msync, like the PPC440.
Differential Revision: https://reviews.llvm.org/D76614
For folding pattern `x-(fma y,z,u*v) -> (fma -y,z,(fma -u,v,x))`, if
`yz` is 1, `uv` is -1 and `x` is -0, sign of result would be changed.
Differential Revision: https://reviews.llvm.org/D76419
Adds/changes some types in the ByVal cc test so that they aren't all
structs of arrays of bytes, and adds testing for passing multiple
ByVal arguments.
The zero sized structs force creation of a stack object of size 1, align
8 in the locals area, but otherwise have no effect on the calling convention
code. i.e. They consume no registers or stack space in the paramater save area.
The 32-bit codegen has 8 bytes of padding to fit the new stack object so
stack size stays the same. 64-bit codegen has no padding in the stack
frames allocated so 8 bytes is added, and becuase of 16-byte aligned
stack, the stack size increases from 112 bytes to 128.
This is the first of a series of patches that adds caller support for
by-value arguments. This patch add support for arguments that are passed in a
single GPR.
There are 3 limitation cases:
-The by-value argument is larger than a single register.
-There are no remaining GPRs even though the by-value argument would
otherwise fit in a single GPR.
-The by-value argument requires alignment greater than register width.
Future patches will be required to add support for these cases as well
as for the callee handling (in LowerFormalArguments_AIX) that
corresponds to this work.
Differential Revision: https://reviews.llvm.org/D75863
If it is a*b-c*d, it could be also folded into fma(a, b, -c*d) or fma(-c, d, a*b).
This patch is trying to respect the uses of a*b and c*d to make the best choice.
Differential Revision: https://reviews.llvm.org/D75982
ISD::ROTL/ROTR rotation values are guaranteed to act as a modulo amount, so for power-of-2 bitwidths we only need the lowest bits.
Differential Revision: https://reviews.llvm.org/D76201
Summary:
This is a part of the series of efforts for correcting alignment of memory operations.
(Another related bugs: https://bugs.llvm.org/show_bug.cgi?id=44388 , https://bugs.llvm.org/show_bug.cgi?id=44543 )
This fixes https://bugs.llvm.org/show_bug.cgi?id=43880 by giving default alignment of loads to 1.
The test CodeGen/AArch64/bcmp-inline-small.ll should have been changed; it was introduced by https://reviews.llvm.org/D64805 . I talked with @evandro, and confirmed that the test is okay to be changed.
Other two tests from PowerPC needed changes as well, but fixes were straightforward.
Reviewers: courbet
Reviewed By: courbet
Subscribers: nlopes, gchatelet, wuzish, nemanjai, kristof.beyls, hiraditya, steven.zhang, danielkiss, llvm-commits, evandro
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D76113
Summary:
On 32-bit PPC target[AIX and BE], when we convert an `i64` to `f32`, a `setcc` operand expansion is needed. The expansion will set the result type of expanded `setcc` operation based on if the subtarget use CRBits or not. If the subtarget does use the CRBits, like AIX and BE, then it will set the result type to `i1`, leading to an inconsistency with original `setcc` result type[i32].
And the reason why it crashed underneath is because we don't set result type of setcc consistent in those two places.
This patch fixes this problem by setting original setcc opnode result type also with `getSetCCResultType` interface.
Reviewers: sfertile, cebowleratibm, hubert.reinterpretcast, Xiangling_L
Reviewed By: sfertile
Subscribers: wuzish, nemanjai, hiraditya, kbarton, jsji, shchenz, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D75702
This patch is intend to implement the missing P8 MacroFusion for LLVM
according to Power8 User's Manual Section 10.1.12 Instruction Fusion
Differential Revision: https://reviews.llvm.org/D70651
Handle LinkOnceODRLinkage;
Handle AppendingLinkage type for llvm.global_ctors/dtors static init global arrays;
Differential Revision: https://reviews.llvm.org/D75305
The new behavior matches GNU objdump. A pair of angle brackets makes tests slightly easier.
`.foo:` is not unique and thus cannot be used in a `CHECK-LABEL:` directive.
Without `-LABEL`, the CHECK line can match the `Disassembly of section`
line and causes the next `CHECK-NEXT:` to fail.
```
Disassembly of section .foo:
0000000000001634 .foo:
```
Bdragon: <> has metalinguistic connotation. it just "feels right"
Reviewed By: rupprecht
Differential Revision: https://reviews.llvm.org/D75713
This is a follow up to the previous patch: [AIX] Implement caller
arguments passed in stack memory.
This corrects a defect in AIX 64-bit where an i32 is written to the
stack with stw (4 bytes) rather than the expected std (8 bytes.) Integer
arguments pass on the stack as images of their register representation.
I also took the opportunity to tidy up some of the calling convention
AIX tests I added in my last commit. This patch adds the missed assembly
expected output for the stack arg int case, which would have caught this
problem.
Differential Revision: https://reviews.llvm.org/D75126
PowerPC hits an assertion due to somewhat the same reason as https://reviews.llvm.org/D70975.
Though there are already some hack, it still failed with some case, when the operand 0 is NOT
a const fp, it is another fma that with const fp. And that const fp is negated which result in multi-uses.
A better fix is to check the uses of the negated const fp. If there are already use of its negated
value, we will have benefit as no extra Node is added.
Differential revision: https://reviews.llvm.org/D75501
The expected output is erroneous and will be corrected alongside a fix
to ensure stack arguments are widened to register width before writing
to the parameter save area.
SUMMARY:
1.if there is a gap between the end virtual address of one section and the beginning virtual address of the next section, the XCOFFObjectWriter.cpp will hit a assert.
2.as discussed in the patch https://reviews.llvm.org/D66969,
since implemented the function description. We can output the raw object data for function.
we need to create a test for raw text section content and test section header for xcoff object file.
Reviewer: daltenty,hubert.reinterpretcast,jasonliu
Differential Revision: https://reviews.llvm.org/D71845
We can only report the knownbits for a SCALAR_TO_VECTOR node if we only demand the 0'th element - the upper elements are undefined and shouldn't be trusted.
This is causing a number of regressions that need addressing but we need to get the bugfix in first.
Summary:
We need to handle the MCSA_LGlobal case in emitSymbolAttribute for functions marked internal in the IR so that the
appropriate storage class is emitted on the function descriptor csect. As part of this we need to make sure that external
labels are not emitted into the symbol table, so we don't emit the descriptor label in the object writing path.
Reviewers: jasonliu, DiggerLin, hubert.reinterpretcast
Reviewed By: jasonliu
Subscribers: Xiangling_L, wuzish, nemanjai, hiraditya, jsji, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D74968
Allow all ExternalSymbolSDNode on AIX, and rely on the linker error to find
symbols which we don't have definitions from any library/compiler-rt.
Differential Revision: https://reviews.llvm.org/D75075
Summary:
The patch D62993 : `[PowerPC] Emit scalar min/max instructions with unsafe fp math`
has modified the functionality when `Subtarget.hasP9Vector() && (!HasNoInfs || !HasNoNaNs)`,
this modification is not expected.
Reviewed By: nemanjai
Differential Revision: https://reviews.llvm.org/D74701
Summary:
Function descriptor csect on AIX should be 4 byte align instead of 1 byte align.
Reviewer: daltenty
Differential Revision: https://reviews.llvm.org/D74974
Extends the existing support for spilling and restoring the condition
register to the linkage area for 32-bit targets, and enables for AIX.
Differential Revision: https://reviews.llvm.org/D74349
Summary:
When we have a long name for the undefined symbol, we would hit this assertion:
Assertion failed: I != StringIndexMap.end() && "String is not in table!"
This patch addresses that.
Reviewed by: DiggerLin, daltenty
Differential Revision: https://reviews.llvm.org/D74924
We have the InstAlias rules for 32-bit rotate but missing the 64-bit one.
Rotate left immediate rotlwi ra,rs,n rlwinm ra,rs,n,0,31
Rotate left rotlw ra,rs,rb rlwnm ra,rs,rb,0,31
Differential Revision: https://reviews.llvm.org/D72676
On Powerpc, set instruction count as lsr first priority of lsr by default.
Add an option ppc-lsr-no-insns-cost to return back to default lsr cost model.
Reviewed By: steven.zhang, jsji
Differential Revision: https://reviews.llvm.org/D72683
This reverts commit 80a34ae311 with fixes.
Previously, since bots turning on EXPENSIVE_CHECKS are essentially turning on
MachineVerifierPass by default on X86 and the fact that
inline-asm-avx-v-constraint-32bit.ll and inline-asm-avx512vl-v-constraint-32bit.ll
are not expected to generate functioning machine code, this would go
down to `report_fatal_error` in MachineVerifierPass. Here passing
`-verify-machineinstrs=0` to make the intent explicit.
This reverts commit 80a34ae311 with fixes.
On bots llvm-clang-x86_64-expensive-checks-ubuntu and
llvm-clang-x86_64-expensive-checks-debian only,
llc returns 0 for these two tests unexpectedly. I tweaked the RUN line a little
bit in the hope that LIT is the culprit since this change is not in the
codepath these tests are testing.
llvm\test\CodeGen\X86\inline-asm-avx-v-constraint-32bit.ll
llvm\test\CodeGen\X86\inline-asm-avx512vl-v-constraint-32bit.ll
Exploit native VSX rounding instruction, x(v|s)r(d|s)pic, which does
rounding using current rounding mode.
According to C standard library, rint may raise INEXACT exception while
nearbyint won't.
Reviewed By: lkail
Differential Revision: https://reviews.llvm.org/D72685
These tests fail when the default is switched to assume IEEE denormal
handling. I'm not sure if PPC really has a way to control the denormal
input handling.
An option is added for PowerPC to disable use of non-volatile CR
register fields and avoid CR spilling in the prologue.
Differential Revision: https://reviews.llvm.org/D69835
Added support for the intrinsic llvm.ppc.dcbfl and llvm.ppc.dcbflp.
These will be used for emitting cache control instructions dcbfl and dcbflp
which are actually mnemonics for using dcbf instruction with different
immediate arguments.
dcbfl ra, rb -> dcbf ra, rb, 1
dcbflp, ra, rb -> dcbf ra, rb, 3
Differential Revision: https://reviews.llvm.org/D68411
This reverts commit rGcd5b308b828e, rGcd5b308b828e, rG8cedf0e2994c.
There are issues to be investigated for polly bots and bots turning on
EXPENSIVE_CHECKS.
This patch:
- enable frame pointer for AIX;
- update some of red zone comments;
- add/update testcases;
Differential Revision: https://reviews.llvm.org/D72454
SUMMARY:
The patch is enable to support Mergeable2ByteCString and Mergeable4ByteCString
Reviewers: daltenty
Subscribers: wuzish, nemanjai, hiraditya
Differential Revision: https://reviews.llvm.org/D74164
On little endian targets prior to Power9, we spill vector registers using a
swapping store (i.e. stdxvd2x saves the vector with the two doublewords in
big endian order regardless of endianness). This is generally not a problem
since we restore them using the corresponding swapping load (lxvd2x). However
if the restore is done by the unwinder, the vector register contains data in
the incorrect order.
This patch fixes that by using Altivec loads/stores for vector saves and
restores in PEI (which keep the order correct) under those specific conditions:
- EH aware function
- Subtarget requires swaps for VSX memops (Little Endian prior to Power9)
Differential revision: https://reviews.llvm.org/D73692
hasReservedSpillSlot returns a dummy frame index of '0' on PPC64 for the
non-volatile condition registers, which leads to the CalleSavedInfo
either referencing an unrelated stack object, or an invalid object if
there are no stack objects. The latter case causes the mir-printer to
crash due to assertions that checks if the frame index referenced by a
CalleeSavedInfo is valid.
To fix the problem create an immutable FixedStack object at the correct offset
in the linkage area of the previous stack frame (ie SP + positive offset).
Differential Revision: https://reviews.llvm.org/D73709
Printing floating point number in decimal is inconvenient for humans.
Verbose asm output will print out floating point values in comments, it
helps.
But in lots of cases, users still need additional work to covert the
decimal back to hex or binary to check the bit patterns,
especially when there are small precision difference.
Hexadecimal form is one of the supported form in LLVM IR, and easier for
debugging.
This patch try to print all FP constant in hex form instead.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D73566
This patch implements the caller side of placing function call arguments
in stack memory. This removes the current limitation where LLVM on AIX
will report fatal error when arguments can't be contained in registers.
There is a particular oddity that a float argument that passes in a
register and also in stack memory requires that the caller initialize
both. From what AIX "ABI" documentation I have it's not clear that this
needs to be done, however, it is necessary for compatibility with the
AIX XL compiler so I think it's best to implement it the same way.
Note a later patch will follow to address the callee side.
Differential Revision: https://reviews.llvm.org/D73209
This reverts commit ed29dbaafa.
I'm backing out D68945, which as the discussion for D73526 shows, doesn't
seem to handle the -O0 path through the codegen backend correctly. I'll
reland the patch when a fix is worked out, apologies for all the churn.
The two parent commits are part of this revert too.
Conflicts:
llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
llvm/test/DebugInfo/X86/dbg-addr-dse.ll
SelectionDAGBuilder conflict is due to a nearby change in e39e2b4a79
that's technically unrelated. dbg-addr-dse.ll conflicted because
41206b61e3 (legitimately) changes the order of two lines.
There are further modifications to dbg-value-func-arg.ll: it landed after
the patch being reverted, and I've converted indirection to be represented
by the isIndirect field rather than DW_OP_deref.
Summary:
The AIX assembler .space directive can't take a second non-zero argument to fill
with. But LLVM emitFill currently assumes it can. We add a flag to the AsmInfo
to check if non-zero fill is supported, and if we can't zerofill non-zero values
we just splat the .byte directives.
Reviewers: stevewan, sfertile, DiggerLin, jasonliu, Xiangling_L
Reviewed By: jasonliu
Subscribers: Xiangling_L, wuzish, nemanjai, hiraditya, kbarton, jsji, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73554
The code paths in the absence of TargetMachine, TargetLowering or
TargetRegisterInfo are poorly tested. As rL285987 said, requiring
TargetPassConfig allows us to delete many (untested) checks littered
everywhere.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D73754
Summary:
This patch intends to support three most common relocation type
on AIX: R_POS, R_TOC, R_RBR.
These three relocation type will be needed for object file generation
on AIX for small code model.
We will have follow up patches to bring relocation support for
large code model on AIX.
Reviewers: hubert.reinterpretcast, daltenty, DiggerLin
Differential Revision: https://reviews.llvm.org/D72027
By adding the prefixed instructions the branch distances are no longer
computed correctly. Since prefixed instructions cannot cross a 64 byte
boundary we have to assume that a prefixed instruction may have a nop
prepended to it. This patch tries to take that nop into consideration
when computing the size of basic blocks.
Differential Revision: https://reviews.llvm.org/D72572
Add the prefixed instructions pld and pstd to future CPU. These are load and
store instructions that require new operand types that are 34 bits. This patch
adds the two instructions as well as the operand types required.
Note that this patch also makes a minor change to tablegen to account for the
fact that some instructions are going to require shifts greater than 31 bits
for the new 34 bit instructions.
Differential Revision: https://reviews.llvm.org/D72574
Future CPU will include support for prefixed instructions.
These prefixed instructions are formed by a 4 byte prefix
immediately followed by a 4 byte instruction effectively
making an 8 byte instruction. The new instruction paddi
is a prefixed form of addi.
This patch adds paddi and all of the support required
for that instruction. The majority of the patch deals with
supporting the new prefixed instructions. The addition of
paddi is mainly to allow for testing.
Differential Revision: https://reviews.llvm.org/D72569
StackColoring::remapInstructions() remaps MachineOperand frame index (e.g. %stack.1 -> %stack.0)
but does not remap FixedStackPseudoSourceValue frame index (e.g. store 4 into %stack.1.ap2.i.i)
referenced by MachineMemoryOperand.
This can cause an assertion failure when LiveDebugValues references a dead stack object.
It is difficult to craft a test case. -g, va_copy and stack-coloring are required.
I can only reproduce it on ppc32.
Summary:
This patch could be treated as a rebase of D33960. It also fixes PR35547.
A fix for `llvm/test/Other/close-stderr.ll` is proposed in D68164. Seems
the consensus is that the test is passing by chance and I'm not
sure how important it is for us. So it is removed like in D33960 for now.
The rest of the test fixes are just adding `--crash` flag to `not` tool.
** The reason it fixes PR35547 is
`exit` does cleanup including calling class destructor whereas `abort`
does not do any cleanup. In multithreading environment such as ThinLTO or JIT,
threads may share states which mostly are ManagedStatic<>. If faulting thread
tearing down a class when another thread is using it, there are chances of
memory corruption. This is bad 1. It will stop error reporting like pretty
stack printer; 2. The memory corruption is distracting and nondeterministic in
terms of error message, and corruption type (depending one the timing, it
could be double free, heap free after use, etc.).
Reviewers: rnk, chandlerc, zturner, sepavloff, MaskRay, espindola
Reviewed By: rnk, MaskRay
Subscribers: wuzish, jholewinski, qcolombet, dschuff, jyknight, emaste, sdardis, nemanjai, jvesely, nhaehnle, sbc100, arichardson, jgravelle-google, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, lenary, s.egerton, pzheng, cfe-commits, MaskRay, filcab, davide, MatzeB, mehdi_amini, hiraditya, steven_wu, dexonsmith, rupprecht, seiya, llvm-commits
Tags: #llvm, #clang
Differential Revision: https://reviews.llvm.org/D67847
These intrinsics and the corresponding ISD nodes were recently added. PPC has
instructions that do this for vectors. Legalize them and add patterns to emit
the satuarting instructions.
Differential revision: https://reviews.llvm.org/D71940
SUMMARY:
In this patch we put the global variable in a Csect which's SectionKind is "ReadOnlyWithRel" into Data Section.
Reviewers: hubert.reinterpretcast,jasonliu,Xiangling_L
Subscribers: wuzish, nemanjai, hiraditya
Differential Revision: https://reviews.llvm.org/D72461
For memcpy/memset/memmove etc., replace ExternalSymbolSDNode with a
MCSymbolSDNode, which have a prefix dot before function name as entry
point symbol.
Differential Revision: https://reviews.llvm.org/D70718
We need to ensure that fpexcept.strict nodes are not optimized away even if
the result is unused. To do that, we need to chain them into the block's
terminator nodes, like already done for PendingExcepts.
This patch adds two new lists of pending chains, PendingConstrainedFP and
PendingConstrainedFPStrict to hold constrained FP intrinsic nodes without
and with fpexcept.strict markers. This allows not only to solve the above
problem, but also to relax chains a bit further by no longer flushing all
FP nodes before a store or other memory access. (They are still flushed
before nodes with other side effects.)
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D72341
Summary:
This patch pushes the AIX vararg unimplemented error diagnostic later
and allows vararg calls so long as all the arguments can be passed in register.
This patch extends the AIX calling convention implementation to initialize
GPR(s) for vararg float arguments. On AIX, both GPR(s) and FPR are allocated
for floating point arguments. The GPR(s) are only initialized for vararg calls,
otherwise the callee is expected to retrieve the float argument in the FPR.
f64 in AIX PPC32 requires special handling in order to allocated and
initialize 2 GPRs. This is performed with bitcast, SRL, truncation to
initialize one GPR for the MSW and bitcast, truncations to initialize
the other GPR for the LSW.
A future patch will follow to add support for arguments passed on the stack.
Patch provided by: cebowleratibm
Reviewers: sfertile, ZarkoCA, hubert.reinterpretcast
Differential Revision: https://reviews.llvm.org/D71013