This is the first use of D(L,B) addressing, which required a fair bit
of surgery. For that reason, the patch just adds the instruction
definition and the associated assembler and disassembler support.
A later patch will actually make use of it for codegen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185433 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, an invalid instruction like:
foo %r1, %r0
would generate the rather odd error message:
....: error: unknown token in expression
foo %r1, %r0
^
We now get the more informative:
....: error: invalid instruction
foo %r1, %r0
^
The same would happen if an address were used where a register was expected.
We now get "invalid operand for instruction" instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182644 91177308-0d34-0410-b5e6-96231b3b80d8
The idea is to make sure that:
(1) "register expected" is restricted to cases where ParseRegister()
is called and the token obviously isn't a register.
(2) "invalid register" is restricted to cases where a register-like "%..."
sequence is found, but the "..." makes no sense.
(3) the generic "invalid operand for instruction" is used in cases where
the wrong register type is used (GPR instead of FPR, etc.).
(4) the new "invalid register pair" is used if the register has the right type,
but is not a valid register pair.
Testing of (1)-(3) is now restricted to regs-bad.s. It uses a representative
instruction for each register class to make sure that only registers from
that class are accepted.
(4) is tested by both regs-bad.s (which checks all invalid register pairs)
and insn-bad.s (which tests one invalid pair for each instruction that
requires a pair).
While there, I changed "Number" to "Num" for consistency with the
operand class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182643 91177308-0d34-0410-b5e6-96231b3b80d8
The GNU assembler treats things like:
brasl %r14, 100
in the same way as:
brasl %r14, .+100
rather than as a branch to absolute address 100. We implemented this in
LLVM by creating an immediate operand rather than the usual expr operand,
and by handling immediate operands specially in the code emitter.
This was undesirable for (at least) three reasons:
- the specialness of immediate operands was exposed to the backend MC code,
rather than being limited to the assembler parser.
- in disassembly, an immediate operand really is an absolute address.
(Note that this means reassembling printed disassembly can't recreate
the original code.)
- it would interfere with any assembly manipulation that we might
try in future. E.g. operations like branch shortening can change
the relative position of instructions, but any code that updates
sym+offset addresses wouldn't update an immediate "100" operand
in the same way as an explicit ".+100" operand.
This patch changes the implementation so that the assembler creates
a "." label for immediate PC-relative operands, so that the operand
to the MCInst is always the absolute address. The patch also adds
some error checking of the offset.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181773 91177308-0d34-0410-b5e6-96231b3b80d8
The SystemZ port currently relies on the order of the instruction operands
matching the order of the instruction field lists. This isn't desirable
for disassembly, where the two are matched only by name. E.g. the R1 and R2
fields of an RR instruction should have corresponding R1 and R2 operands.
The main complication is that addresses are compound operands,
and as far as I know there is no mechanism to allow individual
suboperands to be selected by name in "let Inst{...} = ..." assignments.
Luckily it doesn't really matter though. The SystemZ instruction
encoding groups all address fields together in a predictable order,
so it's just as valid to see the entire compound address operand as
a single field. That's the approach taken in this patch.
Matching by name in turn means that the operands to COPY SIGN and
CONVERT TO FIXED instructions can be given in natural order.
(It was easier to do this at the same time as the rename,
since otherwise the intermediate step was too confusing.)
No functional change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181771 91177308-0d34-0410-b5e6-96231b3b80d8
This adds the actual lib/Target/SystemZ target files necessary to
implement the SystemZ target. Note that at this point, the target
cannot yet be built since the configure bits are missing. Those
will be provided shortly by a follow-on patch.
This version of the patch incorporates feedback from reviews by
Chris Lattner and Anton Korobeynikov. Thanks to all reviewers!
Patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181203 91177308-0d34-0410-b5e6-96231b3b80d8
