The sub-registers explicitly listed in SubRegs in the .td files form a
tree. In a complicated register bank, it is possible to have
sub-register relationships across sub-trees. For example, the ARM NEON
double vector Q0_Q1 is a tree:
Q0_Q1 = [Q0, Q1], Q0 = [D0, D1], Q1 = [D2, D3]
But we also define the DPair register D1_D2 = [D1, D2] which is fully
contained in Q0_Q1.
This patch teaches TableGen to find such sub-register relationships, and
assign sub-register indices to them. In the example, TableGen will
create a dsub_1_dsub_2 sub-register index, and add D1_D2 as a
sub-register of Q0_Q1.
This will eventually enable the coalescer to handle copies of skewed
sub-registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156587 91177308-0d34-0410-b5e6-96231b3b80d8
The .td files specify a tree of sub-registers. Store that tree as
ExplicitSubRegs lists in CodeGenRegister instead of extracting it from
the Record when needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156555 91177308-0d34-0410-b5e6-96231b3b80d8
This mapping is for internal use by TableGen. It will not be exposed in
the generated files.
Unfortunately, the mapping is not completely well-defined. The X86 xmm
registers appear with multiple sub-register indices in the ymm
registers. This is because of the odd idempotent sub_sd and sub_ss
sub-register indices. I hope to be able to eliminate them entirely, so
we can require the sub-registers to form a tree.
For now, just place the canonical sub_xmm index in the mapping, and
ignore the idempotents.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156519 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, if an instruction definition was missing the mnemonic,
the next line would just assert(). Issue a real diagnostic instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156263 91177308-0d34-0410-b5e6-96231b3b80d8
This is still a topological ordering such that every register class gets
a smaller enum value than its sub-classes.
Placing the smaller spill sizes first makes a difference for the
super-register class bit masks. When looking for a super-register class,
we usually want the smallest possible kind of super-register. That is
now available as the first bit set in the bit mask.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156222 91177308-0d34-0410-b5e6-96231b3b80d8
This manually enumerated list of super-register classes has been
superceeded by the automatically computed super-register class masks
available through SuperRegClassIterator.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156151 91177308-0d34-0410-b5e6-96231b3b80d8
This is a pointer into one of the tables used by
getMatchingSuperRegClass(). It makes it possible to use a shared
implementation of that function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156121 91177308-0d34-0410-b5e6-96231b3b80d8
The RC->getSubClassMask() pointer now points to a sequence of register
class bit masks. The first bit mask is the normal sub-class mask. The
following masks are super-reg class masks used by
getMatchingSuperRegClass().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156120 91177308-0d34-0410-b5e6-96231b3b80d8
Many register classes only have a few super-registers, so it is not
necessary to keep individual bit masks for all possible sub-register
indices.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156083 91177308-0d34-0410-b5e6-96231b3b80d8
Some targets have no sub-registers at all. Use the TargetRegisterInfo
versions of composeSubRegIndices(), getSubClassWithSubReg(), and
getMatchingSuperRegClass() for those targets.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156075 91177308-0d34-0410-b5e6-96231b3b80d8
When an instruction match is found, but the subtarget features it
requires are not available (missing floating point unit, or thumb vs arm
mode, for example), issue a diagnostic that identifies what the feature
mismatch is.
rdar://11257547
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155499 91177308-0d34-0410-b5e6-96231b3b80d8
Assembly matchers for instructions with a two-operand form. ARM is full
of these, for example:
add {Rd}, Rn, Rm // Rd is optional and is the same as Rn if omitted.
The property TwoOperandAliasConstraint on the instruction definition controls
when, and if, an alias will be formed. No explicit InstAlias definitions
are required.
rdar://11255754
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155172 91177308-0d34-0410-b5e6-96231b3b80d8
There's almost always a small number of instruction operands, so
use a SmallVector and save on heap allocations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155143 91177308-0d34-0410-b5e6-96231b3b80d8
Handle mixing allocatable and unallocatable register gracefully.
Simplify the pruning of register unit sets.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154474 91177308-0d34-0410-b5e6-96231b3b80d8
This is a new algorithm that finds sets of register units that can be
used to model registers pressure. This handles arbitrary, overlapping
register classes. Each register class is associated with a (small)
list of pressure sets. These are the dimensions of pressure affected
by the register class's liveness.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154374 91177308-0d34-0410-b5e6-96231b3b80d8
This is a new algorithm that associates registers with weighted
register units to accuretely model their effect on register
pressure. This handles registers with multiple overlapping
subregisters. It is possible, but almost inconceivable that the
algorithm fails to find an exact solution for a target description. If
an exact solution cannot be found, an inexact, but reasonable solution
will be chosen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154373 91177308-0d34-0410-b5e6-96231b3b80d8
This also avoids emitting the information twice, which led to code bloat. On i386-linux-Release+Asserts
with all targets built this change shaves a whopping 1.3 MB off clang. The number is probably exaggerated
by recent inliner changes but the methods were already enormous with the old inline cost computation.
The DWARF reg -> LLVM reg mapping doesn't seem to have holes in it, so it could be a simple lookup table.
I didn't implement that optimization yet to avoid potentially changing functionality.
There is still some duplication both in tablegen and the generated code that should be cleaned up eventually.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153837 91177308-0d34-0410-b5e6-96231b3b80d8
First small step toward modeling multi-register multi-pressure. In the
future, register units can also be used to model liveness and
aliasing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153794 91177308-0d34-0410-b5e6-96231b3b80d8
Use an explicit comparator instead of the default.
The sets are sorted, but not using the default comparator. Hopefully,
this will unbreak the Linux builders.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153772 91177308-0d34-0410-b5e6-96231b3b80d8
TableGen emits lists of sub-registers, super-registers, and overlaps. Put
them all in a single table and use a SequenceToOffsetTable to share
suffixes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153761 91177308-0d34-0410-b5e6-96231b3b80d8
This is similar to the StringToOffsetTable we use to produce string
tables, but it can be used for other sequences than strings, and it
eliminates entries for suffixes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153760 91177308-0d34-0410-b5e6-96231b3b80d8
The arm_neon intrinsics can create virtual registers from the DPair
register class which allows both even-odd and odd-even D-register pairs.
This fixes PR12389.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153603 91177308-0d34-0410-b5e6-96231b3b80d8
We cannot limit the concatenated instruction names to 64K. ARM is
already at 32K, and it is easy to imagine a target with more
instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152817 91177308-0d34-0410-b5e6-96231b3b80d8
This patch limited the concatenated register names to 64K which meant
that the total number of registers was many times less than 64K.
If any compilers actually enforce the 64K limit on string literals, and
it turns out to be a problem, we should fix that problem by not using
long string literals.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152816 91177308-0d34-0410-b5e6-96231b3b80d8
~0U might be i32 on 32-bit hosts, then (uint64_t)~0U might not be expected as (i64)0xFFFFFFFF_FFFFFFFF, but as (i64)0x00000000_FFFFFFFF.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152407 91177308-0d34-0410-b5e6-96231b3b80d8
Original commit message:
Use uint16_t to store InstrNameIndices in MCInstrInfo. Add asserts to protect all 16-bit string table offsets. Also make sure the string to offset table string is not larger than 65536 characters since larger string literals aren't portable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152296 91177308-0d34-0410-b5e6-96231b3b80d8
Original commit message:
Use uint16_t to store InstrNameIndices in MCInstrInfo. Add asserts to protect
all 16-bit string table offsets. Also make sure the string to offset table
string is not larger than 65536 characters since larger string literals aren't
portable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152233 91177308-0d34-0410-b5e6-96231b3b80d8
With the new composite physical registers to represent arbitrary pairs
of DPR registers, we don't need the pseudo-registers anymore. Get rid of
a bunch of them that use DPR register pairs and just use the real
instructions directly instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152045 91177308-0d34-0410-b5e6-96231b3b80d8
- Shrink the opcode field to 16 bits.
- Shrink the AsmVariantID field to 8 bits.
- Store the mnemonic string in a string table, store a 16 bit index.
- Store a pascal-style length byte in the string instead of a null terminator,
so we can avoid calling strlen on every entry we visit during mnemonic search.
Shrinks X86AsmParser.o from 434k to 201k on x86_64 and eliminates relocs from the table.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151984 91177308-0d34-0410-b5e6-96231b3b80d8
Allows us to de-virtualize the function and provides access to it in
the instruction printer, which is useful for handling composite
physical registers (e.g., ARM register lists).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151815 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit 151760.
We want to move getSubReg() from TargetRegisterInfo into MCRegisterInfo,
but to do that, the type of the lookup table needs to be the same for
all targets.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151814 91177308-0d34-0410-b5e6-96231b3b80d8
This allows us to make TRC non-polymorphic and value-initializable, eliminating a huge static
initializer and a ton of cruft from the generated code.
Shrinks ARMBaseRegisterInfo.o by ~100k.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151806 91177308-0d34-0410-b5e6-96231b3b80d8
- The search bounds are constant, in the worst case (ARM target) it will scan over 30 uint16_ts.
- This method isn't very hot, I had problems finding a testcase where it's called more than a dozen of times (no perf impact).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151773 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of nested switch statements, use a lookup table. On ARM, this replaces
a 23k (x86_64 release build) function with a 16k table. Its not unlikely to
be faster, as well.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151751 91177308-0d34-0410-b5e6-96231b3b80d8
This requires some gymnastics to make it available for C code. Remove the names
from the disassembler tables, making them relocation free.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150303 91177308-0d34-0410-b5e6-96231b3b80d8
Make them accessible through MCInstrInfo. They are only used for debugging purposes so this doesn't
have an impact on performance. X86MCTargetDesc.o goes from 630K to 461K on x86_64.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150245 91177308-0d34-0410-b5e6-96231b3b80d8
When adding the {-1, -1} entry to the DFAStateInputTable, we
need to increment the index used to populate the DFAStateEntryTable.
Otherwise, the entry table will be off by one for each transition
after the {-1, -1} entry. PR11908.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149713 91177308-0d34-0410-b5e6-96231b3b80d8