Commit Graph

12 Commits

Author SHA1 Message Date
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 fdc4c6b426 Revert "RegScavenging: Add scavengeRegisterBackwards()"
The ppc64 multistage bot fails on this.

This reverts commit r279124.

Also Revert "CodeGen: Add/Factor out LiveRegUnits class; NFCI" because it depends on the previous change
This reverts commit r279171.

llvm-svn: 279199
2016-08-19 03:03:24 +00:00
Matthias Braun 075d0c23d5 RegScavenging: Add scavengeRegisterBackwards()
Re-apply r276044 with off-by-1 instruction fix for the reload placement.

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: 279124
2016-08-18 19:47:59 +00:00
Matthias Braun 5b9722d6c7 Revert "RegScavenging: Add scavengeRegisterBackwards()"
Reverting this commit for now as it seems to be causing failures on
test-suite tests on the clang-ppc64le-linux-lnt bot.

This reverts commit r276044.

llvm-svn: 276068
2016-07-20 00:21:32 +00:00
Matthias Braun 84fd4bee6c RegScavenging: Add scavengeRegisterBackwards()
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: 276044
2016-07-19 22:37:09 +00:00
Petar Jovanovic e578e970cb [mips] Make Static a default relocation model for MIPS codegen
This change follows up defaults for GCC and Clang, so LLVM does not differ
from them. While number of the test files are touched with this change, they
all keep the old (expected) behaviour with the explicit option:
"-relocation-model=pic"
The tests that have not been touched are insensitive to relocation model.

Differential Revision: http://reviews.llvm.org/D17995

llvm-svn: 265949
2016-04-11 15:24:23 +00:00
Paul Robinson a2550a6da3 Have 'optnone' respect the -fast-isel=false option.
This is primarily useful for debugging optnone v. ISel issues.

Differential Revision: http://reviews.llvm.org/D14792

llvm-svn: 254335
2015-11-30 21:56:16 +00:00
Vasileios Kalintiris 2041b1dd0b [mips][FastISel] Remove hidden mips-fast-isel option.
Summary:
This hidden option would disable code generation through FastISel by
default. It was removed from the available options and from the
Fast-ISel tests that required it in order to run the tests.

Reviewers: dsanders

Subscribers: qcolombet, llvm-commits

Differential Revision: http://reviews.llvm.org/D11610

llvm-svn: 243638
2015-07-30 12:39:33 +00:00
Vasileios Kalintiris bb698c7d5f [mips] Add support for dynamic stack realignment.
Summary:
With this change we are able to realign the stack dynamically, whenever it
contains objects with alignment requirements that are larger than the
alignment specified from the given ABI.

We have to use the $fp register as the frame pointer when we perform
dynamic stack realignment. In complex stack frames, with variably-sized
objects, we reserve additionally the callee-saved register $s7 as the
base pointer in order to reference locals.

Reviewers: dsanders

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D8633

llvm-svn: 238829
2015-06-02 13:14:46 +00:00
Petar Jovanovic e0de8f4efb [Mips] Return false for isFPCloseToIncomingSP()
On Mips, frame pointer points to the same side of the frame as the stack
pointer. This function is used to decide where to put register scavenging
spill slot. So far, it was put on the wrong side of the frame, and thus it
was too far away from $fp when frame was larger than 2^15 bytes.

Patch by Vladimir Radosavljevic.

http://reviews.llvm.org/D8895

llvm-svn: 237153
2015-05-12 17:14:05 +00:00