Commit Graph

22 Commits

Author SHA1 Message Date
Dan Gohman
9f23dee08c Start function numbering at 0.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101638 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-17 16:29:15 +00:00
Chris Lattner
736a6ea3a2 Change the scheduler from adding nodes in allnodes order
to adding them in a determinstic order (bottom up from 
the root) based on the structure of the graph itself.

This updates tests for some random changes, interesting
bits: CodeGen/Blackfin/promote-logic.ll no longer crashes.
I have no idea why, but that's good right?

CodeGen/X86/2009-07-16-LoadFoldingBug.ll also fails, but
now compiles to have one fewer constant pool entry, making
the expected load that was being folded disappear.  Since it
is an unreduced mass of gnast, I just removed it.

This fixes PR6370


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97023 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-24 06:11:37 +00:00
Evan Cheng
d40d03e1bd Teach dag combine to fold the following transformation more aggressively:
(OP (trunc x), (trunc y)) -> (trunc (OP x, y))

Unfortunately this simple change causes dag combine to infinite looping. The problem is the shrink demanded ops optimization tend to canonicalize expressions in the opposite manner. That is badness. This patch disable those optimizations in dag combine but instead it is done as a late pass in sdisel.

This also exposes some deficiencies in dag combine and x86 setcc / brcond lowering. Teach them to look pass ISD::TRUNCATE in various places.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92849 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-06 19:38:29 +00:00
Dan Gohman
aceba31b7a Delete useless trailing semicolons.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92740 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 17:55:26 +00:00
Jakob Stoklund Olesen
6ad8c84d70 Move Blackfin intrinsics into the Target/Blackfin directory.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84194 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-15 18:50:52 +00:00
Evan Cheng
0e6b590b91 Coalescer should not delete extract_subreg, insert_subreg, and subreg_to_reg of
physical registers. This is especially critical for the later two since they
start the live interval of a super-register. e.g.
%DO<def> = INSERT_SUBREG %D0<undef>, %S0<kill>, 1
If this instruction is eliminated, the register scavenger will not be happy as
D0 is not defined previously.
This fixes PR5055.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82968 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-28 05:28:43 +00:00
Dan Gohman
fce288fc91 Eliminate more uses of llvm-as and llvm-dis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81293 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-09 00:09:15 +00:00
Jakob Stoklund Olesen
7d927212de Add XFAIL testcase for setcc undef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79093 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-15 12:10:22 +00:00
Jakob Stoklund Olesen
ea60d3d9f2 Add XFAIL test case for a scavenger assert.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79092 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-15 12:09:56 +00:00
Jakob Stoklund Olesen
7a1e872564 Update LocalRewriter::DistanceMap when inserting stack loads.
In the included test case, a stack load was not included in DistanceMap. That
caused TransferDeadness to ignore the instruction, leading to a scavenger
assert.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79090 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-15 11:03:03 +00:00
Jakob Stoklund Olesen
8c54a62061 Rebuild RegScavenger::DistanceMap each time it is needed.
The register scavenger maintains a DistanceMap that maps MI pointers to their
distance from the top of the current MBB. The DistanceMap is built
incrementally in forward() and in bulk in findFirstUse(). It is used by
scavengeRegister() to determine which candidate register has the longest
unused interval.

Unfortunately the DistanceMap contents can become outdated. The first time
scavengeRegister() is called, the DistanceMap is filled to cover the MBB. If
then instructions are inserted in the MBB (as they always are following
scavengeRegister()), the recorded distances are too short. This causes bad
behaviour in the included test case where a register use /after/ the current
position is ignored because findFirstUse() thinks is is /before/ the current
position. A "using an undefined register" assertion follows promptly.

The fix is to build a fresh DistanceMap at the top of scavengeRegister(), and
discard it after use. This means that DistanceMap is no longer needed as a
RegScavenger member variable, and forward() doesn't need to update it.

The fix then discloses issue number two in the same test case: The candidate
search in scavengeRegister() finds a CSR that has been saved in the prologue,
but is currently unused. It would be both inefficient and wrong to spill such
a register in the emergency spill slot. In the present case, the emergency
slot restore is placed immediately before the normal epilogue restore, leading
to a "Redefining a live register" assertion.

Fix number two: When scavengerRegister() stumbles upon an unused register that
is overwritten later in the MBB, return that register early. It is important
to verify that the register is defined later in the MBB, otherwise it might be
an unspilled CSR.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78650 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-11 06:25:12 +00:00
Jakob Stoklund Olesen
46151de6a0 Add support for READCYCLECOUNTER in Blackfin back-end.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78506 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-08 21:42:22 +00:00
Jakob Stoklund Olesen
17421d81fd Don't build illegal ops in DAGCombiner::SimplifyBinOpWithSameOpcodeHands().
Blackfin supports and/or/xor on i32 but not on i16. Teach
DAGCombiner::SimplifyBinOpWithSameOpcodeHands to not produce illegal nodes
after legalize ops.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78497 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-08 20:42:17 +00:00
Evan Cheng
6ade93bbdc Turn some insert_subreg, extract_subreg, subreg_to_reg into implicit_defs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78151 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-05 03:53:14 +00:00
Jakob Stoklund Olesen
ded2e3b0d0 LowerSubregsInstructionPass::LowerExtract should not extend the live range of registers.
When LowerExtract eliminates an EXTRACT_SUBREG with a kill flag, it moves the
kill flag to the place where the sub-register is killed. This can accidentally
overlap with the use of a sibling sub-register, and we have trouble.

In the test case we have this code:

Live Ins: %R0 %R1 %R2
	%R2L<def> = EXTRACT_SUBREG %R2<kill>, 1
	%R2H<def> = LOAD16fi <fi#-1>, 0, Mem:LD(2,4) [FixedStack-1 + 0]
	%R1L<def> = EXTRACT_SUBREG %R1<kill>, 1
	%R0L<def> = EXTRACT_SUBREG %R0<kill>, 1
	%R0H<def> = ADD16 %R2H<kill>, %R2L<kill>, %AZ<imp-def>, %AN<imp-def>, %AC0<imp-def>, %V<imp-def>, %VS<imp-def>

subreg: CONVERTING: %R2L<def> = EXTRACT_SUBREG %R2<kill>, 1
subreg: eliminated!
subreg: killed here: %R0H<def> = ADD16 %R2H, %R2L, %R2<imp-use,kill>, %AZ<imp-def>, %AN<imp-def>, %AC0<imp-def>, %V<imp-def>, %VS<imp-def>

The kill flag on %R2 is moved to the last instruction, and the live range overlaps with the definition of %R2H:

*** Bad machine code: Redefining a live physical register ***
- function:    f
- basic block:  0x18358c0 (#0)
- instruction: %R2H<def> = LOAD16fi <fi#-1>, 0, Mem:LD(2,4) [FixedStack-1 + 0]
Register R2H was defined but already live.

The fix is to replace EXTRACT_SUBREG with IMPLICIT_DEF instead of eliminating
it completely:

subreg: CONVERTING: %R2L<def> = EXTRACT_SUBREG %R2<kill>, 1
subreg: replace by: %R2L<def> = IMPLICIT_DEF %R2<kill>

Note that these IMPLICIT_DEF instructions survive to the asm output. It is
necessary to fix the stack-color-with-reg test case because of that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78093 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-04 20:01:11 +00:00
Jakob Stoklund Olesen
1391cc19d0 Remove unneeded intrinsics from Blackfin backend.
__builtin_bfin_ones does the same as ctpop, so it can be implemented in the front-end.

__builtin_bfin_loadbytes loads from an unaligned pointer with the disalignexcpt instruction. It does the same as loading from a pointer with the low bits masked. It is better if the front-end creates a masked load. We can always instruction select the masked to disalignexcpt+load.

We keep csync/ssync/idle. These intrinsics represent instructions that need workarounds for some silicon revisions. We may even want to convert inline assembler to intrinsics to enable the workarounds.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77917 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-02 21:49:05 +00:00
Jakob Stoklund Olesen
b36eb9df20 Fix issue in regscavenger when scavenging a callee-saved register that has not been spilled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77912 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-02 20:29:41 +00:00
Jakob Stoklund Olesen
ece4818516 Never add a kill flag to a constrained physical register in a two-addr instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77906 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-02 19:13:03 +00:00
Jakob Stoklund Olesen
0e6a4efdd4 Scavenger asserts.
Allow imp-def and imp-use of anything in the scavenger asserts, just like the machine code verifier.
Allow redefinition of a sub-register of a live register.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77904 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-02 18:28:41 +00:00
Jakob Stoklund Olesen
6b30f5c867 Add some basic blackfin intrinsics.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77903 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-02 18:28:11 +00:00
Jakob Stoklund Olesen
63cc527fbc Inline assembly support for Blackfin.
We use the same constraints as GCC, including those that are slightly insane for inline assembler.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77899 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-02 17:39:17 +00:00
Jakob Stoklund Olesen
d950941e13 Analog Devices Blackfin back-end.
Generate code for the Blackfin family of DSPs from Analog Devices:

  http://www.analog.com/en/embedded-processing-dsp/blackfin/processors/index.html
  
We aim to be compatible with the exsisting GNU toolchain found at:

  http://blackfin.uclinux.org/gf/project/toolchain
  
The back-end is experimental.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77897 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-02 17:32:10 +00:00