Represent the operand value as it will be encoded in the instruction. This
allows removing the specialized encoder and decoder methods entirely. Add
an assembler match class while we're at it to lay groundwork for parsing the
thumb shift instructions.
llvm-svn: 137879
Thumb one requires that many arithmetic instruction forms have an 'S'
suffix. For Thumb2, the whether the suffix is required or precluded depends
on whether the instruction is in an IT block. Use target parser predicates
to check for these sorts of context-sensitive constraints.
llvm-svn: 137746
Allow a target assembly parser to do context sensitive constraint checking
on a potential instruction match. This will be used, for example, to handle
Thumb2 IT block parsing.
llvm-svn: 137675
More parsing support for indexed loads. Fix pre-indexed with writeback
parsing for register offsets and handle basic post-indexed offsets.
llvm-svn: 136982
Memory operand parsing is a bit haphazzard at the moment, in no small part
due to the even more haphazzard representations of memory operands in the .td
files. Start cleaning that all up, at least a bit.
The addressing modes in the .td files will be being simplified to not be
so monolithic, especially with regards to immediate vs. register offsets
and post-indexed addressing. addrmode3 is on its way with this patch, for
example.
This patch is foundational to enable going back to smaller incremental patches
for the individual memory referencing instructions themselves. It does just
enough to get the basics in place and handle the "make check" regression tests
we already have.
Follow-up work will be fleshing out the details and adding more robust test
cases for the individual instructions, starting with ARM mode and moving from
there into Thumb and Thumb2.
llvm-svn: 136845
Fix the instruction encoding for operands. Refactor mode to use explicit
instruction definitions per FIXME to be more consistent with loads/stores.
Fix disassembler accordingly. Add tests.
llvm-svn: 136509
Fill in the missing fixed bits and the register operand bits of the instruction
encoding. Refactor the definition to make the mode explicit, which is
consistent with how loads and stores are normally represented and makes
parsing much easier. Add parsing aliases for pseudo-instruction variants.
Update the disassembler for the new representations. Add tests for parsing and
encoding.
llvm-svn: 136479
Add parsing support for BLX (immediate). Since the register operand version is
predicated and the label operand version is not, we have to use some special
handling to get the operand list right for matching.
llvm-svn: 136406
Add parsing support that handles converting the lsb+width source into the
odd way we represent the instruction (an inverted bitfield mask).
llvm-svn: 136399
This can happen in cases where TableGen generated asm matcher cannot check
whether a register operand is in the right register class. e.g. mem operands.
rdar://8204588
llvm-svn: 136292
Encode the width operand as it encodes in the instruction, which simplifies
the disassembler and the encoder, by using the imm1_32 operand def. Add a
diagnostic for the context-sensitive constraint that the width must be in
the range [1,32-lsb].
llvm-svn: 136264
Fix the Rn register encoding for both SSAT and USAT. Update the parsing of the
shift operand to correctly handle the allowed shift types and immediate ranges
and issue meaningful diagnostics when an illegal value or shift type is
specified. Add aliases to parse an ommitted shift operand (default value of
'lsl #0').
Add tests for diagnostics and proper encoding.
llvm-svn: 135990