Commit Graph

13 Commits

Author SHA1 Message Date
Jakob Stoklund Olesen
8a3eab9b20 Remove the local register allocator.
Please use the fast allocator instead.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106051 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-15 21:58:33 +00:00
Jakob Stoklund Olesen
0c9e4f5f3f Only use clairvoyance when defining a register, and then only if it has one use.
This makes allocation independent on the ordering of use-def chains.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103935 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-17 04:50:57 +00:00
Jakob Stoklund Olesen
4bf4bafcce Take allocation hints from copy instructions to/from physregs.
This causes way more identity copies to be generated, ripe for coalescing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103686 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-13 00:19:43 +00:00
Jakob Stoklund Olesen
85f4fdaed4 Enable a bunch more -regalloc=fast tests
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103531 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-12 00:11:24 +00:00
Dale Johannesen
55f9adf543 Adjust register numbers in tests to compensate for the
new lack of R2.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96407 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-16 22:31:31 +00:00
Dale Johannesen
9a6636b2cd Reapply 95050 with a tweak to check the register class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95183 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-03 01:40:33 +00:00
Dale Johannesen
62a04136d5 Test revert 95050; there's a good chance it's causing
buildbot failure.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95103 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 18:52:56 +00:00
Dale Johannesen
5ce0ee9c09 Make local RA smarter about reusing input register of a copy
as output.  Needed for (functional) correctness in inline asm,
and should be generally beneficial.  7361612.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95050 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 02:08:02 +00:00
Dale Johannesen
fc49bd2447 Do better with physical reg operands (typically, from inline asm)
in local register allocator.  If a reg-reg copy has a phys reg
input and a virt reg output, and this is the last use of the phys
reg, assign the phys reg to the virt reg.  If a reg-reg copy has
a phys reg output and we need to reload its spilled input, reload
it directly into the phys reg than passing it through another reg.

Following 76208, there is sometimes no dependency between the def of
a phys reg and its use; this creates a window where that phys reg
can be used for spilling (this is true in linear scan also).  This
is bad and needs to be fixed a better way, although 76208 works too
well in practice to be reverted.  However, there should normally be
no spilling within inline asm blocks.  The patch here goes a long way
towards making this actually be true.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91485 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-16 00:29:41 +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
Evan Cheng
5379f412bc Fix PR3149. If an early clobber def is a physical register and it is tied to an input operand, it effectively extends the live range of the physical register. Currently we do not have a good way to represent this.
172     %ECX<def> = MOV32rr %reg1039<kill>
180     INLINEASM <es:subl $5,$1
        sbbl $3,$0>, 10, %EAX<def>, 14, %ECX<earlyclobber,def>, 9, %EAX<kill>,
36, <fi#0>, 1, %reg0, 0, 9, %ECX<kill>, 36, <fi#1>, 1, %reg0, 0
188     %EAX<def> = MOV32rr %EAX<kill>
196     %ECX<def> = MOV32rr %ECX<kill>
204     %ECX<def> = MOV32rr %ECX<kill>
212     %EAX<def> = MOV32rr %EAX<kill>
220     %EAX<def> = MOV32rr %EAX
228     %reg1039<def> = MOV32rr %ECX<kill>

The early clobber operand ties ECX input to the ECX def.

The live interval of ECX is represented as this:
%reg20,inf = [46,47:1)[174,230:0)  0@174-(230) 1@46-(47)

The right way to represent this is something like
%reg20,inf = [46,47:2)[174,182:1)[181:230:0)  0@174-(182) 1@181-230 @2@46-(47)

Of course that won't work since that means overlapping live ranges defined by two val#.

The workaround for now is to add a bit to val# which says the val# is redefined by a early clobber def somewhere. This prevents the move at 228 from being optimized away by SimpleRegisterCoalescing::AdjustCopiesBackFrom.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61259 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-19 20:58:01 +00:00
Dale Johannesen
8e3455ba17 Remove SelectionDag early allocation of registers
for earlyclobbers.  Teach Local RA about earlyclobber,
and add some tests for it.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56592 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-24 23:13:09 +00:00
Chris Lattner
27679be2c0 testcase for PR1357
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36598 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-30 21:10:13 +00:00