Because the block-splitting code is multi-purpose, we have to meddle with the
branches when using it to fixup a conditional branch destination. We got the
code right, but forgot to update the CFG so the verifier complained when
expensive checks were on.
Probably harmless since constant-islands comes so late, but best to fix it
anyway.
llvm-svn: 318148
Get rid of the handwritten instruction selector code for handling
G_CONSTANT. This code wasn't checking all the preconditions correctly
anyway, so it's better to leave it to TableGen, which can handle at
least some cases correctly (e.g. MOVi, MOVi16, folding into binary
operations). Also add tests to cover those cases.
llvm-svn: 318146
When we emit a tail call for Armv8-M, but then discover that the caller needs to
save/restore `LR`, we convert the tail call to an ordinary one, since restoring
`LR` takes extra instructions, which may negate the benefits of the tail
call. If the callee, however, takes stack arguments, this conversion is
incorrect, since nothing has been done to pass the stack arguments.
Thus the patch reverts https://reviews.llvm.org/rL294000
Also, we improve the instruction sequence for popping `LR` in the case when we
couldn't immediately find a scratch low register, but we can use as a temporary
one of the callee-saved low registers and restore `LR` before popping other
callee-saves.
Differential Revision: https://reviews.llvm.org/D39599
llvm-svn: 318143
Summary:
This fixes PR35221.
Use pseudo-instructions to let MachineCSE hoist global address computation.
Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D39871
llvm-svn: 318081
When generating table jump code for switch statements, place the jump
table label as the first operand in the various addition instructions
in order to enable addressing mode selectors to better match index
computation and possibly fold them into the addressing mode of the
table entry load instruction.
Differential revision: https://reviews.llvm.org/D39752
llvm-svn: 318033
* The method getRegAllocationHints() is now of bool type instead of void. If
true is returned, regalloc (AllocationOrder) will *only* try to allocate the
hints, as opposed to merely trying them before non-hinted registers.
* TargetRegisterInfo::getRegAllocationHints() is implemented for SystemZ with
an increase in number of LOCRs.
In this case, it is desired to force the hints even though there is a slight
increase in spilling, because if a non-hinted register would be allocated,
the LOCRMux pseudo would have to be expanded with a jump sequence. The LOCR
(Load On Condition) SystemZ instruction must have both operands in either the
low or high part of the 64 bit register.
Reviewers: Quentin Colombet and Ulrich Weigand
https://reviews.llvm.org/D36795
llvm-svn: 317879
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.
llvm-svn: 317647
This changes the interface of how targets describe how to legalize, see
the below description.
1. Interface for targets to describe how to legalize.
In GlobalISel, the API in the LegalizerInfo class is the main interface
for targets to specify which types are legal for which operations, and
what to do to turn illegal type/operation combinations into legal ones.
For each operation the type sizes that can be legalized without having
to change the size of the type are specified with a call to setAction.
This isn't different to how GlobalISel worked before. For example, for a
target that supports 32 and 64 bit adds natively:
for (auto Ty : {s32, s64})
setAction({G_ADD, 0, s32}, Legal);
or for a target that needs a library call for a 32 bit division:
setAction({G_SDIV, s32}, Libcall);
The main conceptual change to the LegalizerInfo API, is in specifying
how to legalize the type sizes for which a change of size is needed. For
example, in the above example, how to specify how all types from i1 to
i8388607 (apart from s32 and s64 which are legal) need to be legalized
and expressed in terms of operations on the available legal sizes
(again, i32 and i64 in this case). Before, the implementation only
allowed specifying power-of-2-sized types (e.g. setAction({G_ADD, 0,
s128}, NarrowScalar). A worse limitation was that if you'd wanted to
specify how to legalize all the sized types as allowed by the LLVM-IR
LangRef, i1 to i8388607, you'd have to call setAction 8388607-3 times
and probably would need a lot of memory to store all of these
specifications.
Instead, the legalization actions that need to change the size of the
type are specified now using a "SizeChangeStrategy". For example:
setLegalizeScalarToDifferentSizeStrategy(
G_ADD, 0, widenToLargerAndNarrowToLargest);
This example indicates that for type sizes for which there is a larger
size that can be legalized towards, do it by Widening the size.
For example, G_ADD on s17 will be legalized by first doing WidenScalar
to make it s32, after which it's legal.
The "NarrowToLargest" indicates what to do if there is no larger size
that can be legalized towards. E.g. G_ADD on s92 will be legalized by
doing NarrowScalar to s64.
Another example, taken from the ARM backend is:
for (unsigned Op : {G_SDIV, G_UDIV}) {
setLegalizeScalarToDifferentSizeStrategy(Op, 0,
widenToLargerTypesUnsupportedOtherwise);
if (ST.hasDivideInARMMode())
setAction({Op, s32}, Legal);
else
setAction({Op, s32}, Libcall);
}
For this example, G_SDIV on s8, on a target without a divide
instruction, would be legalized by first doing action (WidenScalar,
s32), followed by (Libcall, s32).
The same principle is also followed for when the number of vector lanes
on vector data types need to be changed, e.g.:
setAction({G_ADD, LLT::vector(8, 8)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(16, 8)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(4, 16)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(8, 16)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(2, 32)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(4, 32)}, LegalizerInfo::Legal);
setLegalizeVectorElementToDifferentSizeStrategy(
G_ADD, 0, widenToLargerTypesUnsupportedOtherwise);
As currently implemented here, vector types are legalized by first
making the vector element size legal, followed by then making the number
of lanes legal. The strategy to follow in the first step is set by a
call to setLegalizeVectorElementToDifferentSizeStrategy, see example
above. The strategy followed in the second step
"moreToWiderTypesAndLessToWidest" (see code for its definition),
indicating that vectors are widened to more elements so they map to
natively supported vector widths, or when there isn't a legal wider
vector, split the vector to map it to the widest vector supported.
Therefore, for the above specification, some example legalizations are:
* getAction({G_ADD, LLT::vector(3, 3)})
returns {WidenScalar, LLT::vector(3, 8)}
* getAction({G_ADD, LLT::vector(3, 8)})
then returns {MoreElements, LLT::vector(8, 8)}
* getAction({G_ADD, LLT::vector(20, 8)})
returns {FewerElements, LLT::vector(16, 8)}
2. Key implementation aspects.
How to legalize a specific (operation, type index, size) tuple is
represented by mapping intervals of integers representing a range of
size types to an action to take, e.g.:
setScalarAction({G_ADD, LLT:scalar(1)},
{{1, WidenScalar}, // bit sizes [ 1, 31[
{32, Legal}, // bit sizes [32, 33[
{33, WidenScalar}, // bit sizes [33, 64[
{64, Legal}, // bit sizes [64, 65[
{65, NarrowScalar} // bit sizes [65, +inf[
});
Please note that most of the code to do the actual lowering of
non-power-of-2 sized types is currently missing, this is just trying to
make it possible for targets to specify what is legal, and how non-legal
types should be legalized. Probably quite a bit of further work is
needed in the actual legalizing and the other passes in GlobalISel to
support non-power-of-2 sized types.
I hope the documentation in LegalizerInfo.h and the examples provided in the
various {Target}LegalizerInfo.cpp and LegalizerInfoTest.cpp explains well
enough how this is meant to be used.
This drops the need for LLT::{half,double}...Size().
Differential Revision: https://reviews.llvm.org/D30529
llvm-svn: 317560
This header already includes a CodeGen header and is implemented in
lib/CodeGen, so move the header there to match.
This fixes a link error with modular codegeneration builds - where a
header and its implementation are circularly dependent and so need to be
in the same library, not split between two like this.
llvm-svn: 317379
We're currently bailing out for Thumb targets while lowering formal
parameters, but there used to be some other checks before it, which
could've caused some functions (e.g. those without formal parameters) to
sneak through unnoticed.
llvm-svn: 317312
The generic dag combiner will fold:
(shl (add x, c1), c2) -> (add (shl x, c2), c1 << c2)
(shl (or x, c1), c2) -> (or (shl x, c2), c1 << c2)
This can create constants which are too large to use as an immediate.
Many ALU operations are also able of performing the shl, so we can
unfold the transformation to prevent a mov imm instruction from being
generated.
Other patterns, such as b + ((a << 1) | 510), can also be simplified
in the same manner.
Differential Revision: https://reviews.llvm.org/D38084
llvm-svn: 317197
This is no-functional-change-intended.
This is repackaging the functionality of D30333 (defer switch-to-lookup-tables) and
D35411 (defer folding unconditional branches) with pass parameters rather than a named
"latesimplifycfg" pass. Now that we have individual options to control the functionality,
we could decouple when these fire (but that's an independent patch if desired).
The next planned step would be to add another option bit to disable the sinking transform
mentioned in D38566. This should also make it clear that the new pass manager needs to
be updated to limit simplifycfg in the same way as the old pass manager.
Differential Revision: https://reviews.llvm.org/D38631
llvm-svn: 316835
As far as I can tell, this matches gcc: -mfloat-abi determines the
calling convention for all functions except those explicitly defined as
soft-float in the ARM RTABI.
This change only affects cases where the user specifies -mfloat-abi to
override the default calling convention derived from the target triple.
Fixes https://bugs.llvm.org//show_bug.cgi?id=34530.
Differential Revision: https://reviews.llvm.org/D38299
llvm-svn: 316708
Summary:
This causes a segfault on ARM when (I think) the pass manager is used multiple times.
Reset set the (last) current section to NULL without saving the corresponding LastEMSInfo back into the map. The next use of the streamer then save the LastEMSInfo for the NULL section leaving the LastEMSInfo mapping for the last current section (the one that was there before the reset) NULL which cause the LastEMSInfo to be set to NULL when the section is being used again.
The reuse of the section (pointer) might mean that the map was holding dangling pointers previously which is why I went for clearing the map and resetting the info, making it as similar to the state right after the constructor run as possible. The AArch64 one doesn't have segfault (since LastEMS isn't a pointer) but it seems to have the same issue.
The segfault is likely caused by https://reviews.llvm.org/D30724 which turns LastEMSInfo into a pointer. As mentioned above, it seems that the actual issue was older though.
No test is included since the test is believed to be too complicated for such an obvious fix and not worth doing.
Reviewers: llvm-commits, shankare, t.p.northover, peter.smith, rengolin
Reviewed By: rengolin
Subscribers: mgorny, aemerson, rengolin, javed.absar, kristof.beyls
Differential Revision: https://reviews.llvm.org/D38588
llvm-svn: 316679
We were generating BLX for all the calls, which was incorrect in most
cases. Update ARMCallLowering to generate BL for direct calls, and BLX,
BX_CALL or BMOVPCRX_CALL for indirect calls.
llvm-svn: 316570
Swap the compare operands if the lhs is a shift and the rhs isn't,
as in arm and T2 the shift can be performed by the compare for its
second operand.
Differential Revision: https://reviews.llvm.org/D39004
llvm-svn: 316562
Report a diagnostic when we fail to parse a shift in a memory operand because
the shift type is not an identifier. Without this, we were silently ignoring
the whole instruction.
Differential revision: https://reviews.llvm.org/D39237
llvm-svn: 316441
* Remove the -arm-asm-parser-dev-diags option.
* Use normal DEBUG(dbgs()) printing for the extra development information about
missing diagnostics.
Differential Revision: https://reviews.llvm.org/D39194
llvm-svn: 316423
This is the Thumb encoding, so the Requires list must include IsThumb.
No test because we happen to select the ARM one first, but that's just luck.
Differential Revision: https://reviews.llvm.org/D39190
llvm-svn: 316421
This alias caused a crash when trying to print the "cps #0" instruction in a
diagnostic for thumbv6 (which doesn't have that instruction).
The comment was incorrect, this instruction is UNPREDICTABLE if no flag bits
are set, so I don't think it's worth keeping.
Differential Revision: https://reviews.llvm.org/D39191
llvm-svn: 316420
Before, loop unrolling was only enabled for loops with a single
block. This restriction has been removed and replaced by:
- allow a maximum of two exiting blocks,
- a four basic block limit for cores with a branch predictor.
Differential Revision: https://reviews.llvm.org/D38952
llvm-svn: 316313
This patch implements dynamic stack (re-)alignment for 16-bit Thumb. When
targeting processors, which support only the 16-bit Thumb instruction set
the compiler ignores the alignment attributes of automatic variables and may
silently generate incorrect code.
Differential revision: https://reviews.llvm.org/D38143
llvm-svn: 316289
Reverting to investigate layering effects of MCJIT not linking
libCodeGen but using TargetMachine::getNameWithPrefix() breaking the
lldb bots.
This reverts commit r315633.
llvm-svn: 315637
Merge LLVMTargetMachine into TargetMachine.
- There is no in-tree target anymore that just implements TargetMachine
but not LLVMTargetMachine.
- It should still be possible to stub out all the various functions in
case a target does not want to use lib/CodeGen
- This simplifies the code and avoids methods ending up in the wrong
interface.
Differential Revision: https://reviews.llvm.org/D38489
llvm-svn: 315633
Summary:
Add LLVM_FORCE_ENABLE_DUMP cmake option, and use it along with
LLVM_ENABLE_ASSERTIONS to set LLVM_ENABLE_DUMP.
Remove NDEBUG and only use LLVM_ENABLE_DUMP to enable dump methods.
Move definition of LLVM_ENABLE_DUMP from config.h to llvm-config.h so
it'll be picked up by public headers.
Differential Revision: https://reviews.llvm.org/D38406
llvm-svn: 315590
MCObjectStreamer owns its MCCodeEmitter -- this fixes the types to reflect that,
and allows us to remove the last instance of MCObjectStreamer's weird "holding
ownership via someone else's reference" trick.
llvm-svn: 315531
This adds debug tracing to the table-generated assembly instruction matcher,
enabled by the -debug-only=asm-matcher option.
The changes in the target AsmParsers are to add an MCInstrInfo reference under
a consistent name, so that we can use it from table-generated code. This was
already being used this way for targets that use deprecation warnings, but 5
targets did not have it, and Hexagon had it under a different name to the other
backends.
llvm-svn: 315445
MCObjectStreamer owns its MCAsmBackend -- this fixes the types to reflect that,
and allows us to remove another instance of MCObjectStreamer's weird "holding
ownership via someone else's reference" trick.
llvm-svn: 315410
functions.
This makes the ownership of the resulting MCObjectWriter clear, and allows us
to remove one instance of MCObjectStreamer's bizarre "holding ownership via
someone else's reference" trick.
llvm-svn: 315327
Previously, the code that implemented the GNU assembler aliases for the
LDRD and STRD instructions (where the second register is omitted)
assumed that the input was a valid instruction. This caused assertion
failures for every example in ldrd-strd-gnu-bad-inst.s.
This improves this code so that it bails out if the instruction is not
in the expected format, the check bails out, and the asm parser is run
on the unmodified instruction.
It also relaxes the alias on thumb targets, so that unaligned pairs of
registers can be used. The restriction that Rt must be even-numbered
only applies to the ARM versions of these instructions.
Differential revision: https://reviews.llvm.org/D36732
llvm-svn: 315305
This adds diagnostic strings for the ARM floating-point register
classes, which will be used when these classes are expected by the
assembler, but the provided operand is not valid.
One of these, DPR, requires C++ code to select the correct error
message, as that class contains different registers depending on the
FPU. The rest can all have their diagnostic strings stored in the
tablegen decription of them.
Differential revision: https://reviews.llvm.org/D36693
llvm-svn: 315304
This adds diagnostic strings for the ARM general-purpose register
classes, which will be used when these classes are expected by the
assembler, but the provided operand is not valid.
One of these, rGPR, requires C++ code to select the correct error
message, as that class contains different registers in pre-v8 and v8
targets. The rest can all have their diagnostic strings stored in the
tablegen description of them.
Differential revision: https://reviews.llvm.org/D36692
llvm-svn: 315303
createWinCOFFObjectWriter to WinCOFFObjectWriter's constructor.
Fixes the same ownership issue for COFF that r315245 did for MachO:
WinCOFFObjectWriter takes ownership of its MCWinCOFFObjectTargetWriter, so we
want to pass this through to the constructor via a unique_ptr, rather than a
raw ptr.
llvm-svn: 315257
ELFObjectWriter's constructor.
Fixes the same ownership issue for ELF that r315245 did for MachO:
ELFObjectWriter takes ownership of its MCELFObjectTargetWriter, so we want to
pass this through to the constructor via a unique_ptr, rather than a raw ptr.
llvm-svn: 315254
to MCObjectWriter's constructor.
MCObjectWriter takes ownership of its MCMachObjectTargetWriter argument -- this
patch plumbs that ownership relationship through the constructor (which
previously took raw MCMachObjectTargetWriter*) and the createMachObjectWriter
function.
llvm-svn: 315245
Martin Storsjo