Certain ARM instructions accept 32-bit immediate operands encoded as a 8-bit
integer value (0-255) and a 4-bit rotation (0-30, even). Current ARM assembly
syntax support in LLVM allows the decoded (32-bit) immediate to be specified
as a single immediate operand for such instructions:
mov r0, #4278190080
The ARMARM defines an extended assembly syntax allowing the encoding to be made
more explicit, as in:
mov r0, #255, #8 ; (same 32-bit value as above)
The behaviour of the two instructions can be different w.r.t flags, which is
documented under "Modified immediate constants" in ARMARM. This patch enables
support for this extended syntax at the MC layer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223113 91177308-0d34-0410-b5e6-96231b3b80d8
This instruction form is handled by different AsmOperands now, so the code is
completely dead (and wrong anyway).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219127 91177308-0d34-0410-b5e6-96231b3b80d8
These are system-only instructions for CPUs with virtualization
extensions, allowing a hypervisor easy access to all of the various
different AArch32 registers.
rdar://problem/17861345
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215700 91177308-0d34-0410-b5e6-96231b3b80d8
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)
Changes made by clang-tidy with minor tweaks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215558 91177308-0d34-0410-b5e6-96231b3b80d8
1. it should accept only 4-byte aligned addresses
2. the maximum offset should be 1020
3. it should be encoded with the offset scaled by two bits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185528 91177308-0d34-0410-b5e6-96231b3b80d8
According to the ARM reference manual, constant offsets are mandatory for pre-indexed addressing modes.
The MC disassembler was not obeying this when the offset is 0.
It was producing instructions like: str r0, [r1]!.
Correct syntax is: str r0, [r1, #0]!.
This change modifies the dumping of operands so that the offset is always printed, regardless of its value, when pre-indexed addressing mode is used.
Patch by Mihail Popa <Mihail.Popa@arm.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179398 91177308-0d34-0410-b5e6-96231b3b80d8
This patch replaces the hard coded GPR pair [R0, R1] of
Intrinsic:arm_ldrexd and [R2, R3] of Intrinsic:arm_strexd with
even/odd GPRPair reg class.
Similar to the lowering of atomic_64 operation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168207 91177308-0d34-0410-b5e6-96231b3b80d8
When the operand is a plain immediate rather than a label, print it
as [pc, #imm] like we do for the Thumb2 wide encoding variant.
rdar://12154503
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166991 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
Work in progress. Parsing for non-writeback, single spaced register lists
works now. The rest have the representations better factored, but still
need more to be able to parse properly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146579 91177308-0d34-0410-b5e6-96231b3b80d8
Next step in the ongoing saga of NEON load/store assmebly parsing. Handle
VLD1 instructions that take a two-register register list.
Adjust the instruction definitions to only have the single encoded register
as an operand. The super-register from the pseudo is kept as an implicit def,
so passes which come after pseudo-expansion still know that the instruction
defines the other subregs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142670 91177308-0d34-0410-b5e6-96231b3b80d8
Encode the immediate into its 8-bit form as part of isel rather than later,
which simplifies things for mapping the encoding bits, allows the removal
of the custom disassembler decoding hook, makes the operand printer trivial,
and prepares things more cleanly for handling these in the asm parser.
rdar://10211428
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140834 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137879 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136845 91177308-0d34-0410-b5e6-96231b3b80d8
Start of cleaning this up a bit. First step is to remove the encoder hook by
storing the operand as the bits it'll actually encode to so it can just be
directly used. Map it to the assembly source values 8/16/24 when we print it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136152 91177308-0d34-0410-b5e6-96231b3b80d8
The immediate is in the range 1-32, but is encoded as 0-31 in a 5-bit bitfield.
Update the representation such that we store the operand as 0-31, allowing us
to remove the encoder method and the special case handling in the disassembler.
Update the assembly parser and the instruction printer accordingly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135823 91177308-0d34-0410-b5e6-96231b3b80d8
