Commit Graph

3 Commits

Author SHA1 Message Date
Francis Visoiu Mistrih c71cced0aa [CodeGen] Always use `printReg` to print registers in both MIR and debug
output

As part of the unification of the debug format and the MIR format,
always use `printReg` to print all kinds of registers.

Updated the tests using '_' instead of '%noreg' until we decide which
one we want to be the default one.

Differential Revision: https://reviews.llvm.org/D40421

llvm-svn: 319445
2017-11-30 16:12:24 +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
Sjoerd Meijer 2db2a947f6 [Thumb] Add support for tMUL in the compare instruction peephole optimizer.
We also want to optimise tests like this: return a*b == 0.  The MULS
instruction is flag setting, so we don't need the CMP instruction but can
instead branch on the result of the MULS. The generated instructions sequence
for this example was: MULS, MOVS, MOVS, CMP. The MOVS instruction load the
boolean values resulting from the select instruction, but these MOVS
instructions are flag setting and were thus preventing this optimisation. Now
we first reorder and move the MULS to before the CMP and generate sequence
MOVS, MOVS, MULS, CMP so that the optimisation could trigger. Reordering of the
MULS and MOVS is safe to do because the subsequent MOVS instructions just set
the CPSR register and don't use it, i.e. the CPSR is dead.

Differential Revision: https://reviews.llvm.org/D27990

llvm-svn: 292608
2017-01-20 13:10:12 +00:00