Commit Graph

69288 Commits

Author SHA1 Message Date
Chris Lattner
7975e3ebba rearrange some code, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123136 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 22:39:48 +00:00
Chandler Carruth
fb00e2715b Add a note about the inability to model FP -> int conversions which
perform rounding other than truncation in the IR. Common C code for this
turns into really an LLVM intrinsic call that blocks a lot of further
optimizations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123135 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 22:36:18 +00:00
Chris Lattner
ad19c8c63c Step #3 to improving trip count analysis: If we fold
a + {b,+,stride} into {a+b,+,stride}  (because a is LIV),
then the resultant AddRec is NUW/NSW if the client says it
is.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123133 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 22:31:26 +00:00
Chris Lattner
992efb0378 Step #2 to improve trip count analysis for loops like this:
void f(int* begin, int* end) { std::fill(begin, end, 0); }

which turns into a != exit expression where one pointer is
strided and (thanks to step #1) known to not overflow, and 
the other is loop invariant.

The observation here is that, though the IV is strided by
4 in this case, that the IV *has* to become equal to the
end value.  It cannot "miss" the end value by stepping over
it, because if it did, the strided IV expression would
eventually wrap around.

Handle this by turning A != B into "A-B != 0" where the A-B
part is known to be NUW.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123131 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 22:26:35 +00:00
Jakob Stoklund Olesen
42e9c96392 Remove MachineRegisterInfo::getLastVirtReg(), it was giving wrong results
when no virtual registers have been allocated.

It was only used to resize IndexedMaps, so provide an IndexedMap::resize()
method such that

 Map.grow(MRI.getLastVirtReg());

can be replaced with the simpler

 Map.resize(MRI.getNumVirtRegs());

This works correctly when no virtuals are allocated, and it bypasses the to/from
index conversions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123130 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 21:58:20 +00:00
Chris Lattner
9dddf08eb8 sort this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123129 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 21:31:39 +00:00
Jakob Stoklund Olesen
be97e906e0 Teach TargetRegisterInfo how to cram stack slot indexes in with the virtual and
physical register numbers.

This makes the hack used in LiveInterval official, and lets LiveInterval be
oblivious of stack slots.

The isPhysicalRegister() and isVirtualRegister() predicates don't know about
this, so when a variable may contain a stack slot, isStackSlot() should always
be tested first.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123128 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 21:17:37 +00:00
Chandler Carruth
96b1b6c135 Add a note about a missed FP optimization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123126 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 21:00:19 +00:00
Jakob Stoklund Olesen
43a566519b Fix comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123125 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 19:45:45 +00:00
Chris Lattner
f42685004c fix a few old bugs (found by inspection) where we would zap instructions
without informing memdep.  This could cause nondeterminstic weirdness 
based on where instructions happen to get allocated, and will hopefully
breath some life into some broken testers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123124 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 19:26:10 +00:00
Jakob Stoklund Olesen
2cfa5b4934 Add a forgotten VireReg2IndexFunctor.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123123 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 18:58:33 +00:00
Oscar Fuentes
6abea2b0a4 Apply -fPIC to C sources too.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123122 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 17:38:31 +00:00
Tobias Grosser
aa2be84356 Instcombine: Fix pattern where the sext did not dominate the icmp using it
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123121 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 16:00:11 +00:00
Tobias Grosser
3a723ab344 DominatorTree->print() now prints the status of the DFSNumbers correctly
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123120 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 16:00:09 +00:00
Oscar Fuentes
2c5e0b8b98 Rewrite handling of LLVM_ENABLE_PIC. It was being processed after
config.h was generated, so it had no effect on it.

Thanks to arrowdodger for pointing out this and a tentative patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123119 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 14:34:39 +00:00
Cameron Zwarich
e7d7865bfd LoopInstSimplify preserves LoopSimplify.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123117 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 12:35:16 +00:00
Chandler Carruth
694d753b09 Another missed memset in std::vector initialization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123116 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 11:29:57 +00:00
Cameron Zwarich
f78df5ebb8 Eliminate some extra hash table lookups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123115 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 10:54:21 +00:00
Cameron Zwarich
e272deed7b Add an informative comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123114 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 10:32:30 +00:00
Chandler Carruth
27a2a13b62 Fix a cut-paste-o so that the sample code is correct for my last note.
Also, switch to a more clear 'sink' function with its declaration to
avoid any confusion about 'g'. Thanks for the suggestion Frits.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123113 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 10:10:59 +00:00
Chandler Carruth
e5ca494ae6 Another missed optimization of trivial vector code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123112 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 09:58:36 +00:00
Chandler Carruth
d8723a9b55 Add a note about vector's size-constructor producing dead stores.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123111 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 09:58:33 +00:00
Jakob Stoklund Olesen
0804ead404 Simplify LiveDebugVariables by storing MachineOperand copies locations instead
of using a Location class with the same information.

When making a copy of a MachineOperand that was already stored in a
MachineInstr, it is necessary to clear the parent pointer on the copy. Otherwise
the register use-def lists become inconsistent.

Add MachineOperand::clearParent() to do that. An alternative would be a custom
MachineOperand copy constructor that cleared ParentMI. I didn't want to do that
because of the performance impact.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123109 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 05:33:21 +00:00
Jakob Stoklund Olesen
00f93fc046 Shrink a BitVector that didn't mean to store bits for all physical registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123108 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 03:45:44 +00:00
Jakob Stoklund Olesen
4314268128 Replace TargetRegisterInfo::printReg with a PrintReg class that also works without a TRI instance.
Print virtual registers numbered from 0 instead of the arbitrary
FirstVirtualRegister. The first virtual register is printed as %vreg0.
TRI::NoRegister is printed as %noreg.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123107 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 03:05:53 +00:00
Jakob Stoklund Olesen
994c727b57 Use IndexedMap for MachineRegisterInfo as well. No functional change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123106 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 03:05:46 +00:00
Chris Lattner
6d5a2411aa teach SCEV analysis of PHI nodes that PHI recurences formed
with GEP instructions are always NUW, because PHIs cannot wrap
the end of the address space.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123105 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 02:28:48 +00:00
Chris Lattner
f1859891b7 reduce indentation. Print <nuw> and <nsw> when dumping SCEV AddRec's
that have the bit set.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123104 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 02:16:18 +00:00
Chandler Carruth
75fbd3793f Add a note about a missed memset optimization from std::fill.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123103 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 01:32:55 +00:00
Jakob Stoklund Olesen
b258135301 Fix the last virtual register enumerations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123102 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 23:11:11 +00:00
Jakob Stoklund Olesen
c7d67f90d3 Fix VirtRegMap to use TRI::index2VirtReg and TRI::virtReg2Index instead of
depending on TRI::FirstVirtualRegister.

Also use TRI::printReg instead of printing virtual registers directly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123101 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 23:11:07 +00:00
Jakob Stoklund Olesen
98c5476070 Fix a MachineVerifier loop that probably didn't mean to skip the last two
virtual registers.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123100 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 23:11:02 +00:00
Jakob Stoklund Olesen
3ca2102c72 Don't document exactly how virtual registers are represented as integers. Code
shouldn't depend directly on that.

Give an example of how to iterate over all virtual registers in a function
without depending on the representation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123099 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 23:10:59 +00:00
Jakob Stoklund Olesen
b421c566f5 Use an IndexedMap for LiveVariables::VirtRegInfo.
Provide MRI::getNumVirtRegs() and TRI::index2VirtReg() functions to allow
iteration over virtual registers without depending on the representation of
virtual register numbers.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123098 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 23:10:57 +00:00
Jakob Stoklund Olesen
56e4d89642 Do not talk about TargetRegisterInfo::FirstVirtualRegister.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123097 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 23:10:53 +00:00
Jakob Stoklund Olesen
358de24dc1 Use an IndexedMap for LiveOutRegInfo to hide its dependence on TargetRegisterInfo::FirstVirtualRegister.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123096 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 23:10:50 +00:00
Cameron Zwarich
7c88186309 Fix coding style.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123093 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 22:36:53 +00:00
Chris Lattner
8a629577f8 fix a latent bug in memcpyoptimizer that my recent patches exposed: it wasn't
updating memdep when fusing stores together.  This fixes the crash optimizing
the bullet benchmark.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123091 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 22:19:21 +00:00
Chris Lattner
0468e3e265 tryMergingIntoMemset can only handle constant length memsets.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123090 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 22:11:56 +00:00
Chris Lattner
d90a192279 Merge memsets followed by neighboring memsets and other stores into
larger memsets.  Among other things, this fixes rdar://8760394 and
allows us to handle "Example 2" from http://blog.regehr.org/archives/320,
compiling it into a single 4096-byte memset:

_mad_synth_mute:                        ## @mad_synth_mute
## BB#0:                                ## %entry
	pushq	%rax
	movl	$4096, %esi             ## imm = 0x1000
	callq	___bzero
	popq	%rax
	ret



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123089 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 21:19:19 +00:00
Chris Lattner
9fa11e94b5 fix an issue in IsPointerOffset that prevented us from recognizing that
P and P+1 are relative to the same base pointer.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123087 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 21:07:56 +00:00
Chris Lattner
06511264f8 enhance memcpyopt to merge a store and a subsequent
memset into a single larger memset.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123086 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 20:54:51 +00:00
Chris Lattner
2feee6454d fit in 80 cols
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123085 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 20:53:41 +00:00
Chris Lattner
355f5778aa merge two tests and filecheckify
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123082 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 20:27:22 +00:00
Chris Lattner
67a716ab81 constify TargetData references.
Split memset formation logic out into its own
"tryMergingIntoMemset" helper function.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123081 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 20:24:01 +00:00
Chris Lattner
5d37370a6f When loop rotation happens, it is *very* common for the duplicated condbr
to be foldable into an uncond branch.  When this happens, we can make a
much simpler CFG for the loop, which is important for nested loop cases
where we want the outer loop to be aggressively optimized.

Handle this case more aggressively.  For example, previously on
phi-duplicate.ll we would get this:


define void @test(i32 %N, double* %G) nounwind ssp {
entry:
  %cmp1 = icmp slt i64 1, 1000
  br i1 %cmp1, label %bb.nph, label %for.end

bb.nph:                                           ; preds = %entry
  br label %for.body

for.body:                                         ; preds = %bb.nph, %for.cond
  %j.02 = phi i64 [ 1, %bb.nph ], [ %inc, %for.cond ]
  %arrayidx = getelementptr inbounds double* %G, i64 %j.02
  %tmp3 = load double* %arrayidx
  %sub = sub i64 %j.02, 1
  %arrayidx6 = getelementptr inbounds double* %G, i64 %sub
  %tmp7 = load double* %arrayidx6
  %add = fadd double %tmp3, %tmp7
  %arrayidx10 = getelementptr inbounds double* %G, i64 %j.02
  store double %add, double* %arrayidx10
  %inc = add nsw i64 %j.02, 1
  br label %for.cond

for.cond:                                         ; preds = %for.body
  %cmp = icmp slt i64 %inc, 1000
  br i1 %cmp, label %for.body, label %for.cond.for.end_crit_edge

for.cond.for.end_crit_edge:                       ; preds = %for.cond
  br label %for.end

for.end:                                          ; preds = %for.cond.for.end_crit_edge, %entry
  ret void
}

Now we get the much nicer:

define void @test(i32 %N, double* %G) nounwind ssp {
entry:
  br label %for.body

for.body:                                         ; preds = %entry, %for.body
  %j.01 = phi i64 [ 1, %entry ], [ %inc, %for.body ]
  %arrayidx = getelementptr inbounds double* %G, i64 %j.01
  %tmp3 = load double* %arrayidx
  %sub = sub i64 %j.01, 1
  %arrayidx6 = getelementptr inbounds double* %G, i64 %sub
  %tmp7 = load double* %arrayidx6
  %add = fadd double %tmp3, %tmp7
  %arrayidx10 = getelementptr inbounds double* %G, i64 %j.01
  store double %add, double* %arrayidx10
  %inc = add nsw i64 %j.01, 1
  %cmp = icmp slt i64 %inc, 1000
  br i1 %cmp, label %for.body, label %for.end

for.end:                                          ; preds = %for.body
  ret void
}

With all of these recent changes, we are now able to compile:

void foo(char *X) {
 for (int i = 0; i != 100; ++i) 
   for (int j = 0; j != 100; ++j)
     X[j+i*100] = 0;
}

into a single memset of 10000 bytes.  This series of changes
should also be helpful for other nested loop scenarios as well.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123079 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 19:59:06 +00:00
Chris Lattner
57863b8ee0 make domtree verification print something useful on failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123078 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 19:55:55 +00:00
Chris Lattner
64c24db959 split ssa updating code out to its own helper function. Don't bother
moving the OrigHeader block anymore: we just merge it away anyway so
its code layout doesn't matter.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123077 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 19:26:33 +00:00
Chris Lattner
883401a72f Implement a TODO: Enhance loopinfo to merge away the unconditional branch
that it was leaving in loops after rotation (between the original latch
block and the original header.

With this change, it is possible for rotated loops to have just a single
basic block, which is useful.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123075 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 19:10:28 +00:00
Chris Lattner
dc85f8ab80 various code cleanups, enhance MergeBlockIntoPredecessor to preserve
loop info.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123074 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 19:08:40 +00:00