Commit Graph

7 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 537d039104 RegScavenging: Add scavengeRegisterBackwards()
Re-apply r276044/r279124/r305516. Fixed a problem where we would refuse
to place spills as the very first instruciton of a basic block and thus
artifically increase pressure (test in
test/CodeGen/PowerPC/scavenging.mir:spill_at_begin)

This is a variant of scavengeRegister() that works for
enterBasicBlockEnd()/backward(). The benefit of the backward mode is
that it is not affected by incomplete kill flags.

This patch also changes
PrologEpilogInserter::doScavengeFrameVirtualRegs() to use the register
scavenger in backwards mode.

Differential Revision: http://reviews.llvm.org/D21885

llvm-svn: 305625
2017-06-17 02:08:18 +00:00
Matthias Braun 35530d7129 Revert "RegScavenging: Add scavengeRegisterBackwards()"
Revert because of reports of some PPC input starting to spill when it
was predicted that it wouldn't and no spillslot was reserved.

This reverts commit r305516.

llvm-svn: 305566
2017-06-16 17:48:08 +00:00
Matthias Braun a42c537912 RegScavenging: Add scavengeRegisterBackwards()
Re-apply r276044/r279124. Trying to reproduce or disprove the ppc64
problems reported in the stage2 build last time, which I cannot
reproduce right now.

This is a variant of scavengeRegister() that works for
enterBasicBlockEnd()/backward(). The benefit of the backward mode is
that it is not affected by incomplete kill flags.

This patch also changes
PrologEpilogInserter::doScavengeFrameVirtualRegs() to use the register
scavenger in backwards mode.

Differential Revision: http://reviews.llvm.org/D21885

llvm-svn: 305516
2017-06-15 22:14:55 +00:00
Matthias Braun 8aaa368d00 ARMFrameLowering: Reserve emergency spill slot for large arguments
Re-commit after revert in r300668. Changed getMaxFPOffset() to a
more conservative heuristic instead of trying to be clever and missing
for some exotic calling conventions.

We need to reserve an emergency spill slot in cases with large argument
types that could overflow immediate offsets for FP relative address
calculations.

rdar://31317893

Differential Revision: https://reviews.llvm.org/D31643

llvm-svn: 300761
2017-04-19 21:11:44 +00:00
Renato Golin 742aed8683 Revert "ARMFrameLowering: Reserve emergency spill slot for large arguments"
This reverts commit r300639, as it broke self-hosting on ARM. PR32709.

llvm-svn: 300668
2017-04-19 09:02:52 +00:00
Matthias Braun 661d3d4b00 ARMFrameLowering: Reserve emergency spill slot for large arguments
We need to reserve an emergency spill slot in cases with large argument
types that could overflow immediate offsets for FP relative address
calculations.

rdar://31317893

Differential Revision: https://reviews.llvm.org/D31643

llvm-svn: 300639
2017-04-19 01:16:07 +00:00