Commit Graph

7412 Commits

Author SHA1 Message Date
def548f9a0 BuildLibCalls: Nuke EmitMemCpy, EmitMemMove and EmitMemSet. They are dead and superseded by IRBuilder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122576 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-27 00:25:32 +00:00
a1bf4ca773 SimplifyLibCalls: Use IRBuilder to simplify code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122575 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-27 00:16:46 +00:00
9f39188def have loop-idiom nuke instructions that feed stores that get removed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122574 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-27 00:03:23 +00:00
a92ff91a96 implement enough of the memset inference algorithm to recognize and insert
memsets.  This is still missing one important validity check, but this is enough
to compile stuff like this:

void test0(std::vector<char> &X) {
  for (std::vector<char>::iterator I = X.begin(), E = X.end(); I != E; ++I)
    *I = 0;
}

void test1(std::vector<int> &X) {
  for (long i = 0, e = X.size(); i != e; ++i)
    X[i] = 0x01010101;
}

With:
 $ clang t.cpp -S -o - -O2 -emit-llvm | opt -loop-idiom | opt -O3 | llc 

to:

__Z5test0RSt6vectorIcSaIcEE:            ## @_Z5test0RSt6vectorIcSaIcEE
## BB#0:                                ## %entry
	subq	$8, %rsp
	movq	(%rdi), %rax
	movq	8(%rdi), %rsi
	cmpq	%rsi, %rax
	je	LBB0_2
## BB#1:                                ## %bb.nph
	subq	%rax, %rsi
	movq	%rax, %rdi
	callq	___bzero
LBB0_2:                                 ## %for.end
	addq	$8, %rsp
	ret
...
__Z5test1RSt6vectorIiSaIiEE:            ## @_Z5test1RSt6vectorIiSaIiEE
## BB#0:                                ## %entry
	subq	$8, %rsp
	movq	(%rdi), %rax
	movq	8(%rdi), %rdx
	subq	%rax, %rdx
	cmpq	$4, %rdx
	jb	LBB1_2
## BB#1:                                ## %for.body.preheader
	andq	$-4, %rdx
	movl	$1, %esi
	movq	%rax, %rdi
	callq	_memset
LBB1_2:                                 ## %for.end
	addq	$8, %rsp
	ret



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122573 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-26 23:42:51 +00:00
61db1f56d0 start using irbuilder to make mem intrinsics in a few passes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122572 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-26 22:57:41 +00:00
22920b5986 sketch more of this out.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122567 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-26 20:45:45 +00:00
bb89710ddd move isBytewiseValue out to ValueTracking.h/cpp
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122565 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-26 20:15:01 +00:00
e6bb649ec6 actually add the file...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122563 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-26 19:39:38 +00:00
b0db161f5b Start of a pass for recognizing memset and memcpy idioms.
No functionality yet.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122562 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-26 19:32:44 +00:00
3fed0d917d Simplify code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122561 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-26 15:23:45 +00:00
ae47be1ea0 don't lose TD info
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122556 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-25 20:52:04 +00:00
7569d79de1 switch the inliner alignment enforcement stuff to use the
getOrEnforceKnownAlignment function, which simplifies the code
and makes it stronger.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122555 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-25 20:42:38 +00:00
687140c818 Move getOrEnforceKnownAlignment out of instcombine into Transforms/Utils.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122554 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-25 20:37:57 +00:00
49c7e3e290 Fix a thinko pointed out by Frits van Bommel: looking through global variables in isBytewiseValue is not safe.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122550 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-24 22:23:59 +00:00
a112087e42 MemCpyOpt: Turn memcpys from a constant into a memset if possible.
This allows us to compile "int cst[] = {-1, -1, -1};" into
  movl  $-1, 16(%rsp)
  movq  $-1, 8(%rsp)
instead of
  movl  _cst+8(%rip), %eax
  movl  %eax, 16(%rsp)
  movq  _cst(%rip), %rax
  movq  %rax, 8(%rsp)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122548 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-24 21:17:12 +00:00
ec3953ff95 When determining if we can fold (x >> C1) << C2, the bits that we need to verify are zero
are not the low bits of x, but the bits that WILL be the low bits after the operation completes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122529 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-23 23:56:24 +00:00
d5f8684b16 It is possible for SimplifyCFG to cause PHI nodes to become redundant too late in the optimization
pipeline to be caught by instcombine, and it's not feasible to catch them in SimplifyCFG because the
use-lists are in an inconsistent state at the point where it could know that it need to simplify them.
Instead, have CodeGenPrepare look for trivially redundant PHIs as part of its general cleanup effort.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122516 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-23 20:57:35 +00:00
e90a6333c3 Preserve the address space when generating bitcasts for MemTransferInst in ConvertToScalarInfo
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122462 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-23 01:41:32 +00:00
8e68c38735 Change all self assignments X=X to (void)X, so that we can turn on a
new gcc warning that complains on self-assignments and
self-initializations.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122458 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-23 00:58:24 +00:00
4ac19470dc InstCombine: creating selects from -1 and 0 is fine, they combine into a sext from i1.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122453 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-22 23:12:15 +00:00
37bf92b523 Add a generic expansion transform: A op (B op' C) -> (A op B) op' (A op C)
if both A op B and A op C simplify.  This fires fairly often but doesn't
make that much difference.  On gcc-as-one-file it removes two "and"s and
turns one branch into a select.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122399 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-22 13:36:08 +00:00
a3c44a5280 Add some statistics, good for understanding how much more powerful
instcombine is compared to instsimplify.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122397 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-22 09:40:51 +00:00
f056838956 Give GVN back the ability to perform simple conditional propagation on conditional branch values.
I still think that LVI should be handling this, but that capability is some ways off in the future,
and this matters for some significant benchmarks.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122378 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 23:54:34 +00:00
491e0307a8 Remove dead code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122371 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 22:31:24 +00:00
aad94aa437 GVN's Expression is not POD-like (it contains a SmallVector). Simplify code while at it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122362 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 21:30:19 +00:00
1cd0f4637b Visit instructions deterministically. Use a FIFO so as to approximately
visit instructions before their uses, since InstructionSimplify does a
better job in that case.  All this prompted by Frits van Bommel.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122343 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 17:08:55 +00:00
e95cc25a22 If an instruction simplifies, try again to simplify any uses of it. This is
not very important since the pass is only used for testing, but it does make
it more realistic.  Suggested by Frits van Bommel.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122336 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 16:12:03 +00:00
82fdab3358 Pull a few more simplifications out of instcombine (there are still
plenty left though!), in particular for multiplication.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122330 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 14:00:22 +00:00
69fdf876e1 Oops, forgot to add the pass itself!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122265 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-20 21:07:42 +00:00
43ff68ded0 Add a new convenience pass for testing InstructionSimplify. Previously
it could only be tested indirectly, via instcombine, gvn or some other
pass that makes use of InstructionSimplify, which means that testcases
had to be carefully contrived to dance around any other transformations
that that pass did.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122264 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-20 20:54:37 +00:00
b0de244f23 Add a check missing from my last commit and avoid a potential overflow situation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122258 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-20 20:00:31 +00:00
4dc1ac0947 Reduce indentation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122249 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-20 16:21:59 +00:00
5337f20c15 Teach InstCombine to merge (icmp ult (X + CA), C1) | (icmp eq X, C2) into (icmp ult (X + CA), C1 + 1) if C2 + CA == C1.
InstCombine creates these so now we compile x == 23 || x == 24 || x == 25 to
  %x.off = add i32 %x, -23
  %1 = icmp ult i32 %x.off, 3
instead of
  %x.off = add i32 %x, -23
  %1 = icmp ult i32 %x.off, 2
  %cmp3 = icmp eq i32 %x, 25
  %ret2 = or i1 %1, %cmp3


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122248 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-20 16:18:51 +00:00
2b9375e44b fix PR8807 by making transformConstExprCastCall aware of byval arguments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122238 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-20 08:36:38 +00:00
ab215bc371 various cleanups for transformConstExprCastCall
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122237 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-20 08:25:06 +00:00
0b66f63a26 when eliding a byval copy due to inlining a readonly function, we have
to make sure that the reused alloca has sufficient alignment.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122236 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-20 08:10:40 +00:00
e7ae705c32 pull byval processing out to its own helper function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122235 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-20 07:57:41 +00:00
018fb767b9 fix PR8769, a miscompilation by inliner when inlining a function with a byval
argument.  The generated alloca has to have at least the alignment of the
byval, if not, the client may be making assumptions that the new alloca won't
satisfy.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122234 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-20 07:45:28 +00:00
55fb9b0fcf Avoid dropping the address space when InstCombine optimizes memset
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122215 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-20 01:05:30 +00:00
f2a97ed13d fix an oversight caught by Frits!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122204 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-19 23:24:04 +00:00
459f4f8c25 tidy up
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122190 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-19 20:24:28 +00:00
74b64611c4 move a transformation to a more logical place, simplifying it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122183 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-19 19:43:52 +00:00
e5cbdca3bd recognize an unsigned add with overflow idiom into uadd.
This resolves a README entry and technically resolves PR4916,
but we still get poor code for the testcase in that PR because
GVN isn't CSE'ing uadd with add, filed as PR8817.

Previously we got:

_test7:                                 ## @test7
	addq	%rsi, %rdi
	cmpq	%rdi, %rsi
	movl	$42, %eax
	cmovaq	%rsi, %rax
	ret

Now we get:

_test7:                                 ## @test7
	addq	%rsi, %rdi
	movl	$42, %eax
	cmovbq	%rsi, %rax
	ret



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122182 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-19 19:37:52 +00:00
26b482d7a7 optimize uadd(x, cst) into a comparison when the normal
result is dead.  This is required for my next patch to not
regress the testsuite.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122181 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-19 19:35:32 +00:00
0fe80bbbb6 use IC.ReplaceInstUsesWith instead of a raw RAUW so that uses of
the old thing end up on the instcombine worklist.  Not doing this
can cause an extra top-level iteration of instcombine, burning
compile time.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122179 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-19 18:38:44 +00:00
0a62474830 generalize the sadd creation code to not require that the
sadd formed is half the size of the original type. We can
now compile this into a sadd.i8:

unsigned char X(char a, char b) {
  int res = a+b;
  if ((unsigned )(res+128) > 255U)
    abort();
  return res;
}




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122178 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-19 18:35:09 +00:00
dd7e837374 fix another miscompile in the llvm.sadd formation logic: it wasn't
checking to see if the high bits of the original add result were dead.
Inserting a smaller add and zexting back to that size is not good enough.

This is likely to be the fix for 8816.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122177 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-19 18:22:06 +00:00
368397bb7d fix a bug (possibly 8816) in the sadd forming xform: it isn't
profitable (or safe) to promote code when the add-with-constant
has other uses.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122175 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-19 17:59:02 +00:00
f0f568b49e rework the code added in r122072 to pull it out to its own
helper function, clean up comments, and reduce indentation.
No functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122174 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-19 17:52:50 +00:00
1dec0d2704 Enhance LICM to promote alias sets whose pointers themselves are stored,
which doesn't affect the memory address being promoted.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122172 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-19 05:57:25 +00:00