Commit Graph

17 Commits

Author SHA1 Message Date
Kit Barton 7c80f98b69 [PPC] Remove Darwin support from POWER backend.
This patch issues an error message if Darwin ABI is attempted with the PPC
backend. It also cleans up existing test cases, either converting the test to
use an alternative triple or removing the test if the coverage is no longer
needed.

Updated Tests
-------------
The majority of test cases were updated to use a different triple that does not
include the Darwin ABI. Many tests were also updated to use FileCheck, in place
of grep.

Deleted Tests
-------------
llvm/test/tools/dsymutil/PowerPC/sibling.test was originally added to test
specific functionality of dsymutil using an object file created with an old
version of llvm-gcc for a Powerbook G4. After a discussion with @JDevlieghere he
suggested removing the test.

llvm/test/CodeGen/PowerPC/combine_loads_from_build_pair.ll was converted from a
PPC test to a SystemZ test, as the behavior is also reproducible there.

All other tests that were deleted were specific to the darwin/ppc ABI and no
longer necessary.

Phabricator Review: https://reviews.llvm.org/D50988

llvm-svn: 340795
2018-08-28 01:18:29 +00:00
Matthias Braun 7a482e2302 RegisterScavenging: Followup to r305625
This does some improvements/cleanup to the recently introduced
scavengeRegisterBackwards() functionality:

- Rewrite findSurvivorBackwards algorithm to use the existing
  LiveRegUnit::accumulateBackward() code. This also avoids the Available
  and Candidates bitset and just need 1 LiveRegUnit instance
  (= 1 bitset).
- Pick registers in allocation order instead of register number order.

llvm-svn: 305817
2017-06-20 18:43:14 +00:00
Ehsan Amiri a538b0f023 Adding -verify-machineinstrs option to PowerPC tests
Currently we have a number of tests that fail with -verify-machineinstrs.
To detect this cases earlier we add the option to the testcases with the
exception of tests that will currently fail with this option. PR 27456 keeps
track of this failures.

No code review, as discussed with Hal Finkel.

llvm-svn: 277624
2016-08-03 18:17:35 +00:00
Hal Finkel 7c5cb066d0 [PowerPC] Enable printing instructions using aliases
TableGen had been nicely generating code to print a number of instructions using
shorter aliases (and PowerPC has plenty of short mnemonics), but we were not
calling it. For some of the aliases we support in the parser, TableGen can't
infer the "inverse" alias relationship, so there is still more to do.

Thus, after some hours of updating test cases...

llvm-svn: 235616
2015-04-23 18:30:38 +00:00
Hal Finkel 7fe6a5390f PPC: Enable aggressive anti-dependency breaking
Aggressive anti-dependency breaking is enabled by default for all PPC cores.
This provides a general speedup on the P7 and other platforms (among other
factors, the instruction group formation for the non-embedded PPC cores is done
during post-RA scheduling). In order to do this safely, the incompatibility
between uses of the MFOCRF instruction and anti-dependency breaking are
resolved by marking MFOCRF with hasExtraSrcRegAllocReq. As noted in the removed
FIXME, the problem was that MFOCRF's output is sensitive to the identify of the
source register, and always paired with a shift to undo this effect. Because
anti-dependency breaking is unaware of this hidden dependency of the shift
amount on the source register of the MFOCRF instruction, changing that register
must be inhibited.

Two test cases were adjusted: The SjLj test was made more insensitive to
register choices and scheduling; the saveCR test disabled anti-dependency
breaking because part of what it is testing is proper register reuse.

llvm-svn: 190587
2013-09-12 05:24:49 +00:00
Hal Finkel 035b4825ce Cleanup PPC CR-spill kill flags and 32- vs. 64-bit instructions
There were a few places where kill flags were not being set correctly, and
where 32-bit instruction variants were being used with 64-bit registers. After
r178180, this code was being triggered causing llc to assert.

llvm-svn: 178220
2013-03-28 03:38:16 +00:00
Hal Finkel 0dfbb05aff Use multiple virtual registers in PPC CR spilling
Now that the register scavenger can support multiple spill slots, and PEI can
use virtual-register-based scavenging for multiple simultaneous registers, we
can use a virtual register for the transfer register in the CR spilling code.

This should eliminate the last place (outside of the prologue/epilogue) where
we depend on the unconditional availability of the r0 register. We will soon be
able to allocate it (in a somewhat restricted sense) as a GPR.

llvm-svn: 178060
2013-03-26 18:57:22 +00:00
Hal Finkel bb420f10e9 Allocate the RS spill slot for any PPC function with spills and a large stack frame
For spills into a large stack frame, the FI-elimination code uses the register
scavenger to obtain a free GPR for use with an r+r-addressed load or store.
When there are no available GPRs, the scavenger gets one by using its spill
slot. Previously, we were not always allocating that spill slot and the RS
would assert when the spill slot was needed.

I don't currently have a small test that triggered the assert, but I've
created a small regression test that verifies that the spill slot is now
added when the stack frame is sufficiently large.

llvm-svn: 177140
2013-03-15 05:06:04 +00:00
Hal Finkel 01271c6022 Don't reserve R2 on Darwin/PPC
Now that only the register-scavenger version of the CR spilling code remains,
we no longer need the Darwin R2 hack. Darwin can use R0 as a spare register in
any case where the System V ABI uses it (R0 is special architecturally, and so
is reserved under all common ABIs).

A few test cases needed to be updated to reflect the register-allocation changes.

llvm-svn: 176868
2013-03-12 15:18:14 +00:00
Hal Finkel 692d1fb355 Cleanup stack/frame register define/kill states. This fixes two bugs:
1. The ST*UX instructions that store and update the stack pointer did not set define/kill on R1. This became a problem when I activated post-RA scheduling (and had incorrectly adjusted the Frames-large test).

2. eliminateFrameIndex did not kill its scavenged temporary register, and this could cause the scavenger to exhaust all available registers (and its emergency spill slot) when there were a lot of CR values to spill. The 2010-02-12-saveCR test has been adjusted to check for this.

llvm-svn: 147359
2011-12-30 00:34:00 +00:00
Hal Finkel 67a7f18faf Make CR spill and restore use a reserved register. These operations cannot use the register scavenger because the scavenger can only scavenge one register and frame-index elimination may have already grabbed it.
llvm-svn: 146318
2011-12-10 04:50:53 +00:00
Hal Finkel 0fc34bc2d3 delaying restore-cr changed assigned registers in some tests
llvm-svn: 145963
2011-12-06 20:55:46 +00:00
Hal Finkel 8f6834dfa5 enable PPC register scavenging by default (update tests and remove some FIXMEs)
llvm-svn: 145819
2011-12-05 17:55:17 +00:00
Hal Finkel e18c72689c remove wasted space for extra bit copies of CR2 subregs
llvm-svn: 145817
2011-12-05 17:55:06 +00:00
Hal Finkel d87f7af1f3 specify cpu for test to fix failure on some darwin systems with a g4+ cpu
llvm-svn: 145699
2011-12-02 19:38:17 +00:00
Hal Finkel 9286705955 adjust the instruction ordering in some PPC tests: changes due to postRA haz. rec.
llvm-svn: 145678
2011-12-02 04:58:12 +00:00
Dale Johannesen 26062150fa When save/restoring CR at prolog/epilog, in a large
stack frame, the prolog/epilog code was using the same
register for the copy of CR and the address of the save slot.  Oops.
This is fixed here for Darwin, sort of, by reserving R2 for this case.
A better way would be to do the store before the decrement of SP,
which is safe on Darwin due to the red zone.

SVR4 probably has the same problem, but I don't know how to fix it;
there is no red zone and R2 is already used for something else.
I'm going to leave it to someone interested in that target.

Better still would be to rewrite the CR-saving code completely;
spilling each CR subregister individually is horrible code.

llvm-svn: 96015
2010-02-12 21:35:34 +00:00