Commit Graph

87 Commits

Author SHA1 Message Date
Andrew Trick ff7e4b11b1 Disabled subregister copy coalescing during MachineCSE.
This effectively backs out r197465 but leaves some of the general
fixes in place. Not all targets are ready to handle this feature. To
enable it, some infrastructure work is needed to better handle
register class constraints.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197514 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-17 19:29:36 +00:00
Andrew Trick c4c5a1d526 Allow MachineCSE to coalesce trivial subregister copies the same way that it coalesces normal copies.
Without this, MachineCSE is powerless to handle redundant operations with truncated source operands.

This required fixing the 2-addr pass to handle tied subregisters. It isn't clear what combinations of subregisters can legally be tied, but the simple case of truncated source operands is now safely handled:

     %vreg11<def> = COPY %vreg1:sub_32bit; GR32:%vreg11 GR64:%vreg1
     %vreg12<def> = COPY %vreg2:sub_32bit; GR32:%vreg12 GR64:%vreg2
     %vreg13<def,tied1> = ADD32rr %vreg11<tied0>, %vreg12<kill>, %EFLAGS<imp-def>

Test case: cse-add-with-overflow.ll.

This exposed an existing bug in
PPCInstrInfo::commuteInstruction. Thanks to Rafael for the test case:
PowerPC/crash.ll.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197465 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-17 04:50:45 +00:00
Rafael Espindola 2eead9941a Revert "Allow MachineCSE to coalesce trivial subregister copies the same way that it coalesces normal copies."
This reverts commit r197414.

It broke the ppc64 bootstrap. I will post a testcase in a sec.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197424 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-16 20:57:09 +00:00
Andrew Trick b961a26cec Allow MachineCSE to coalesce trivial subregister copies the same way
that it coalesces normal copies.

Without this, MachineCSE is powerless to handle redundant operations
with truncated source operands.

This required fixing the 2-addr pass to handle tied subregisters. It
isn't clear what combinations of subregisters can legally be tied, but
the simple case of truncated source operands is now safely handled:

     %vreg11<def> = COPY %vreg1:sub_32bit; GR32:%vreg11 GR64:%vreg1
     %vreg12<def> = COPY %vreg2:sub_32bit; GR32:%vreg12 GR64:%vreg2
     %vreg13<def,tied1> = ADD32rr %vreg11<tied0>, %vreg12<kill>, %EFLAGS<imp-def>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197414 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-16 19:36:21 +00:00
Andrew Trick 86d28968fd whitespace
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197413 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-16 19:36:18 +00:00
Craig Topper a0ec3f9b7b Use SmallVectorImpl& instead of SmallVector to avoid repeating small vector size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186274 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-14 04:42:23 +00:00
Chandler Carruth d04a8d4b33 Use the new script to sort the includes of every file under lib.
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169131 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-03 16:50:05 +00:00
Manman Ren 39834da697 CSE: allow PerformTrivialCoalescing to check copies across basic block
boundaries.

Given the following case:
BB0
  %vreg1<def> = SUBrr %vreg0, %vreg7
  %vreg2<def> = COPY %vreg7
BB1
  %vreg10<def> = SUBrr %vreg0, %vreg2
We should be able to CSE between SUBrr in BB0 and SUBrr in BB1.

rdar://12462006


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168717 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-27 18:58:41 +00:00
Jakub Staszak bb8ddc7e4f Don't use iterator after being erased.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168622 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-26 22:14:19 +00:00
Ulrich Weigand b64e2115de Do not consider a machine instruction that uses and defines the same
physical register as candidate for common subexpression elimination
in MachineCSE.

This fixes a bug on PowerPC in MultiSource/Applications/oggenc/oggenc
caused by MachineCSE invalidly merging two separate DYNALLOC insns.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167855 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-13 18:40:58 +00:00
Jakob Stoklund Olesen feab72c20a Remove unused BitVectors from getAllocatableSet().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165999 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-16 00:05:06 +00:00
Jakob Stoklund Olesen fb9ebbf236 Switch most getReservedRegs() clients to the MRI equivalent.
Using the cached bit vector in MRI avoids comstantly allocating and
recomputing the reserved register bit vector.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165983 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-15 21:57:41 +00:00
Benjamin Kramer 5fa2d458af MachineCSE: Hoist isConstantPhysReg out of the loop, it checks for overlaps already.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161729 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-11 20:42:59 +00:00
Benjamin Kramer cfc0ad6e48 PR13578: Teach MachineCSE that instructions that use a constant register can be CSE'd safely.
This is common e.g. when doing rip-relative addressing on x86_64.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161728 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-11 19:05:13 +00:00
Manman Ren 39ad568c62 X86: enable CSE between CMP and SUB
We perform the following:
1> Use SUB instead of CMP for i8,i16,i32 and i64 in ISel lowering.
2> Modify MachineCSE to correctly handle implicit defs.
3> Convert SUB back to CMP if possible at peephole.

Removed pattern matching of (a>b) ? (a-b):0 and like, since they are handled
by peephole now.

rdar://11873276


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161462 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-08 00:51:41 +00:00
Manman Ren ba86b13ad9 MachineCSE: Update the heuristics for isProfitableToCSE.
If the result of a common subexpression is used at all uses of the candidate
expression, CSE should not increase the live range of the common subexpression.

rdar://11393714 and rdar://11819721


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161396 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-07 06:16:46 +00:00
Bill Wendling 96cb112852 Remove tabs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160475 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-19 00:04:14 +00:00
Nick Lewycky 7a7a6db6d7 Remove ParentMap. You can just ask the domnode for its parent. No functionality
change.

Move the "Not profitable, avoid CSE!" debug message next to where we fail the
check for profitability and use a different message for avoiding CSE due to
being in different register classes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159729 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-05 06:19:21 +00:00
Jakob Stoklund Olesen f152fe8d48 Switch some getAliasSet clients to MCRegAliasIterator.
MCRegAliasIterator can optionally visit the register itself, allowing
for simpler code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157837 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-01 20:36:54 +00:00
Craig Topper e4fd907e72 Use uint16_t to store register overlaps to reduce static data.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152001 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-04 10:43:23 +00:00
Jakob Stoklund Olesen 2129a0f677 Handle regmasks in MachineCSE.
Don't attempt to extend physreg live ranges across calls.

<rdar://problem/10942095>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151610 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-28 02:08:50 +00:00
Lang Hames c2e08db4e5 Re-enable 150652 and 150654 - Make FPSCR non-reserved, and make MachineCSE bail on reserved registers. This *should* be safe as of r150786.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150769 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-17 00:27:16 +00:00
Lang Hames 1834df8384 Oop - r150653 + r150654 broke one of my test cases. Backing out for now...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150655 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-16 02:32:10 +00:00
Lang Hames f7e31b9e81 MachineCSE shouldn't extend the live ranges of reserved or allocatable registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150653 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-16 02:19:35 +00:00
Andrew Trick 1dd8c8560d Codegen pass definition cleanup. No functionality.
Moving toward a uniform style of pass definition to allow easier target configuration.
Globally declare Pass ID.
Globally declare pass initializer.
Use INITIALIZE_PASS consistently.
Add a call to the initializer from CodeGen.cpp.
Remove redundant "createPass" functions and "getPassName" methods.

While cleaning up declarations, cleaned up comments (sorry for large diff).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150100 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-08 21:23:13 +00:00