Commit Graph

7 Commits

Author SHA1 Message Date
Puyan Lotfi 43e94b15ea Followup on Proposal to move MIR physical register namespace to '$' sigil.
Discussed here:

http://lists.llvm.org/pipermail/llvm-dev/2018-January/120320.html

In preparation for adding support for named vregs we are changing the sigil for
physical registers in MIR to '$' from '%'. This will prevent name clashes of
named physical register with named vregs.

llvm-svn: 323922
2018-01-31 22:04:26 +00:00
Justin Bogner 6c452834a1 MIR: Print the register class or bank in vreg defs
This updates the MIRPrinter to include the regclass when printing
virtual register defs, which is already valid syntax for the
parser. That is, given 64 bit %0 and %1 in a "gpr" regbank,

  %1(s64) = COPY %0(s64)

would now be written as

  %1:gpr(s64) = COPY %0(s64)

While this change alone introduces a bit of redundancy with the
registers block, it allows us to update the tests to be more concise
and understandable and brings us closer to being able to remove the
registers block completely.

Note: We generally only print the class in defs, but there is one
exception. If there are uses without any defs whatsoever, we'll print
the class on all uses. I'm not completely convinced this comes up in
meaningful machine IR, but for now the MIRParser and MachineVerifier
both accept that kind of stuff, so we don't want to have a situation
where we can print something we can't parse.

llvm-svn: 316479
2017-10-24 18:04:54 +00:00
Matthias Braun 8940114f61 MIParser/MIRPrinter: Compute block successors if not explicitely specified
- MIParser: If the successor list is not specified successors will be
  added based on basic block operands in the block and possible
  fallthrough.

- MIRPrinter: Adds a new `simplify-mir` option, with that option set:
  Skip printing of block successor lists in cases where the
  parser is guaranteed to reconstruct it. This means we still print the
  list if some successor cannot be determined (happens for example for
  jump tables), if the successor order changes or branch probabilities
  being unequal.

Differential Revision: https://reviews.llvm.org/D31262

llvm-svn: 302289
2017-05-05 21:09:30 +00:00
Matthias Braun f80403d8ee RegisterCoalescer: Fix joinReservedPhysReg()
joinReservedPhysReg() can only deal with a liverange in a single basic
block when copying from a vreg into a physreg.

See also rdar://30306405

Differential Revision: https://reviews.llvm.org/D29436

llvm-svn: 294268
2017-02-07 01:59:39 +00:00
Matthias Braun 58f99615d6 Use an actual valid register in test
llvm-svn: 292459
2017-01-19 01:04:08 +00:00
James Y Knight 99a2ce2af2 Check for register clobbers when merging a vreg live range with a
reserved physreg in RegisterCoalescer.

Previously, we only checked for clobbers when merging into a READ of
the physreg, but not when merging from a WRITE to the physreg.

Differential Revision: https://reviews.llvm.org/D28527

llvm-svn: 291942
2017-01-13 19:08:36 +00:00
Matthias Braun 709a4cc238 RegisterCoalscer: Only coalesce complete reserved registers.
The coalescer eliminates copies from reserved registers of the form:
   %vregX = COPY %rY
in the case where %rY is a reserved register. However this turns out to
be invalid if only some of the subregisters are reserved (see also
https://reviews.llvm.org/D26648).

Differential Revision: https://reviews.llvm.org/D26687

llvm-svn: 288428
2016-12-01 22:39:51 +00:00