Commit Graph

114 Commits

Author SHA1 Message Date
Eric Christopher
9f34dd305b Hopefully temporarily revert this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95154 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 23:01:31 +00:00
Eric Christopher
8334f068c4 Reformat my last patch slightly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95147 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 22:29:26 +00:00
Eric Christopher
a6a089cd24 Re-add strcmp and known size object size checking optimization.
Passed bootstrap and nightly test run here.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95145 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 22:10:43 +00:00
Chris Lattner
39ceb471b7 don't turn (A & (C0?-1:0)) | (B & ~(C0?-1:0)) -> C0 ? A : B
for vectors.  Codegen is generating awful code or segfaulting
in various cases (e.g. PR6204).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95058 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 02:43:51 +00:00
Dan Gohman
3b5487e627 LangRef.html says that inttoptr and ptrtoint always use zero-extension
when the cast is extending.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95046 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 01:44:02 +00:00
Chris Lattner
5f670d4131 cleanups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94995 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-01 19:54:45 +00:00
Chris Lattner
d569561835 fix rdar://7590304, a miscompilation of objc apps on arm. The caller
of objc message send was getting marked arm_apcscc, but the prototype
isn't.  This is fine at runtime because objcmsgsend is implemented in
assembly.  Only turn a mismatched caller and callee into 'unreachable'
if the callee is a definition.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94986 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-01 18:11:34 +00:00
Chris Lattner
830f3f205d fix rdar://7590304, an infinite loop in instcombine. In the invoke
case, instcombine can't zap the invoke for fear of changing the CFG.
However, we have to do something to prevent the next iteration of
instcombine from inserting another store -> undef before the invoke
thereby getting into infinite iteration between dead store elim and
store insertion.

Just zap the callee to null, which will prevent the next iteration
from doing anything.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94985 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-01 18:04:58 +00:00
Eli Friedman
be7cfa6033 Simplify/generalize the xor+add->sign-extend instcombine.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94943 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-31 04:29:12 +00:00
Eli Friedman
694488f477 Add a small transform: transform -(X<<Y) to (-X<<Y) when the shift has a single
use and X is free to negate.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94941 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-31 02:30:23 +00:00
Bob Wilson
49db68fba0 Check alignment of loads when deciding whether it is safe to execute them
unconditionally.  Besides checking the offset, also check that the underlying
object is aligned as much as the load itself.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94875 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-30 04:42:39 +00:00
Bob Wilson
6ecfccfd55 Use more specific types to avoid casts. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94863 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-30 00:41:10 +00:00
Bob Wilson
fb2ea6130d Preserve load alignment in instcombine transformations. I've been unable to
create a testcase where this matters.  The select+load transformation only
occurs when isSafeToLoadUnconditionally is true, and in those situations,
instcombine also changes the underlying objects to be aligned.  This seems
like a good idea regardless, and I've verified that it doesn't pessimize
the subsequent realignment.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94850 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 22:39:21 +00:00
Eric Christopher
36664bfc7a Revert my last couple of patches. They appear to have broken bison.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94841 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 21:16:24 +00:00
Bob Wilson
3eb4f7e2dd Improve isSafeToLoadUnconditionally to recognize that GEPs with constant
indices are safe if the result is known to be within the bounds of the
underlying object.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94829 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 19:19:08 +00:00
Duncan Sands
ac512171ff Having RHSKnownZero and RHSKnownOne be alternative names for KnownZero and KnownOne
(via APInt &RHSKnownZero = KnownZero, etc) seems dangerous and confusing to me: it
is easy not to notice this, and then wonder why KnownZero/RHSKnownZero changed
underneath you when you modified RHSKnownZero/KnownZero etc.  So get rid of this.
No intended functionality change (tested with "make check" + llvm-gcc bootstrap).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94802 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 06:18:46 +00:00
Eric Christopher
949124ce0f Add constant support to object size handling and remove default
lowering. We'll either figure it out, or not and be lowered by
SelectionDAGBuild.

Add test.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94775 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 01:09:57 +00:00
Duncan Sands
2c47368a7d Fix PR6165. The bug was that LHSKnownZero was being and'd with DemandedMask
when it should have been and'd with LowBits.  Fix that and while there beef
up the logic in the case of a negative LHS.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94745 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-28 17:22:42 +00:00
Chris Lattner
43b5f9312d make -fno-rtti the default unless a directory builds with REQUIRES_RTTI.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94378 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-24 20:43:08 +00:00
Chris Lattner
abb992d6a3 change the canonical form of "cond ? -1 : 0" to be
"sext cond" instead of a select.  This simplifies some instcombine
code, matches the policy for zext (cond ? 1 : 0 -> zext), and allows
us to generate better code for a testcase on ppc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94339 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-24 00:09:49 +00:00
Chris Lattner
f7d0d163c5 fix a potential overflow issue Eli pointed out.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94336 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 23:31:46 +00:00
Chris Lattner
818ff34bc0 implement a simple instcombine xform that has been in the
readme forever.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94318 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 18:49:30 +00:00
Victor Hernandez
29fa5e9886 Keep ignoring pointer-to-pointer bitcasts
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94194 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-22 19:05:05 +00:00
Chris Lattner
e73a31f667 Stop building RTTI information for *most* llvm libraries. Notable
missing ones are libsupport, libsystem and libvmcore.  libvmcore is
currently blocked on bugpoint, which uses EH.  Once it stops using
EH, we can switch it off.

This #if 0's out 3 unit tests, because gtest requires RTTI information.
Suggestions welcome on how to fix this.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94164 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-22 06:49:46 +00:00
Victor Hernandez
a4c77622f7 No need to look through bitcasts for DbgInfoIntrinsic
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94112 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 23:07:15 +00:00
Chris Lattner
c0404b3715 optimize ~(~X >>s Y) --> (X >>s Y), patch by Edmund Grimley
Evans!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93884 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-19 18:16:19 +00:00
Eric Christopher
d3dc3cc98f Fix comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93831 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-19 01:20:15 +00:00
Chris Lattner
cd5adbbc0c my instcombine transformations to make extension elimination more
aggressive changed the canonical form from sext(trunc(x)) to ashr(lshr(x)),
make sure to transform a couple more things into that canonical form,
and catch a case where we missed turning zext/shl/ashr into a single sext.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93787 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-18 22:19:16 +00:00
Owen Anderson
5b39620e2d Fix comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93679 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-17 06:49:03 +00:00
Bill Wendling
22f3b9faac When the visitSub method was split into visitSub and visitFSub, this xform was
added to the FSub version. However, the original version of this xform guarded
against doing this for floating point (!Op0->getType()->isFPOrFPVector()).

This is causing LLVM to perform incorrect xforms for code like:

void func(double *rhi, double *rlo, double xh, double xl, double yh, double yl){
  double mh, ml;
  double c = 134217729.0;
  double up, u1, u2, vp, v1, v2;
        
  up = xh*c;
  u1 = (xh - up) + up;
  u2 = xh - u1;
        
  vp = yh*c;
  v1 = (yh - vp) + vp;
  v2 = yh - v1;
        
  mh = xh*yh;
  ml = (((u1*v1 - mh) + (u1*v2)) + (u2*v1)) + (u2*v2);
  ml += xh*yl + xl*yh;
        
  *rhi = mh + ml;
  *rlo = (mh - (*rhi)) + ml;
}

The last line was optimized away, but rl is intended to be the difference
between the infinitely precise result of mh + ml and after it has been rounded
to double precision.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93369 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-13 23:23:17 +00:00
Chris Lattner
53af2d13e7 reenable the piece that turns trunc(zext(x)) -> x even if zext has multiple uses,
codegen has no apparent problem with the trunc version of this, because it turns
into a simple subreg idiom


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93202 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11 22:49:40 +00:00
Chris Lattner
a958cbfe36 Disable folding sext(trunc(x)) -> x (and other similar cast/cast cases) when the
trunc has multiple uses.  Codegen is not able to coalesce the subreg case 
correctly and so this leads to higher register pressure and spilling (see PR5997).

This speeds up 256.bzip2 from 8.60 -> 8.04s on my machine, ~7%.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93200 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11 22:45:25 +00:00
Chris Lattner
8e76764de8 add one more bitfield optimization, allowing clang to generate
good code on PR4216:

_test_bitfield:                                             ## @test_bitfield
	orl	$32962, %edi
	movl	$4294941946, %eax
	andq	%rdi, %rax
	ret

instead of:

_test_bitfield:
        movl    $4294941696, %ecx
        movl    %edi, %eax
        orl     $194, %edi
        orl     $32768, %eax
        andq    $250, %rdi
        andq    %rax, %rcx
        movq    %rdi, %rax
        orq     %rcx, %rax
        ret

Evan is looking into the remaining andq+imm -> andl optimization.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93147 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11 06:55:24 +00:00
Chris Lattner
7acc4b1281 Extend CanEvaluateZExtd to handle and/or/xor more aggressively in the
BitsToClear case.  This allows it to promote expressions which have an
and/or/xor after the lshr, promoting cases like test2 (from PR4216) 
and test3 (random extample extracted from a spec benchmark).

clang now compiles the code in PR4216 into:

_test_bitfield:                                             ## @test_bitfield
	movl	%edi, %eax
	orl	$194, %eax
	movl	$4294902010, %ecx
	andq	%rax, %rcx
	orl	$32768, %edi
	andq	$39936, %rdi
	movq	%rdi, %rax
	orq	%rcx, %rax
	ret

instead of:

_test_bitfield:                                             ## @test_bitfield
	movl	%edi, %eax
	orl	$194, %eax
	movl	$4294902010, %ecx
	andq	%rax, %rcx
	shrl	$8, %edi
	orl	$128, %edi
	shlq	$8, %rdi
	andq	$39936, %rdi
	movq	%rdi, %rax
	orq	%rcx, %rax
	ret

which is still not great, but is progress.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93145 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11 04:05:13 +00:00
Chris Lattner
789162a309 Remove the dead TD argument to CanEvaluateZExtd, and add a
new BitsToClear result which allows us to start promoting
expressions that end with a lshr-by-constant.  This is
conservatively correct and better than what we had before
(see testcases) but still needs to be extended further.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93144 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11 03:32:00 +00:00
Chris Lattner
8cf4f6f3dd improve comments, remove dead TD argument to CanEvaluateSExtd.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93143 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11 02:43:35 +00:00
Chris Lattner
11ea812424 teach sext optimization to handle truncs from types that are not
the dest of the sext.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93128 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 20:30:41 +00:00
Chris Lattner
9ee947c224 teach zext optimization how to deal with truncs that don't come from
the zext dest type.  This allows us to handle test52/53 in cast.ll,
and allows llvm-gcc to generate much better code for PR4216 in -m64
mode:

_test_bitfield:                                             ## @test_bitfield
	orl	$32962, %edi
	movl	%edi, %eax
	andl	$-25350, %eax
	ret

This also fixes a bug handling vector extends, ensuring that the
mask produced is a vector constant, not an integer constant.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93127 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 20:25:54 +00:00
Chris Lattner
aa9c894523 simplify CanEvaluateSExtd to return a bool now that we have a
simpler profitability predicate.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93111 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 07:57:20 +00:00
Chris Lattner
6954ceec1a the NumCastsRemoved argument to CanEvaluateSExtd is dead, remove it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93110 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 07:42:21 +00:00
Chris Lattner
dde5ee5d37 now that the cost model has changed, we can always consider
elimination of a sign extend to be a win, which simplifies 
the client of CanEvaluateSExtd, and allows us to eliminate
more casts (examples taken from real code).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93109 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 07:40:50 +00:00
Chris Lattner
f4fb91181c change the preferred canonical form for a sign extension to be
lshr+ashr instead of trunc+sext.  We want to avoid type 
conversions whenever possible, it is easier to codegen expressions
without truncates and extensions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93107 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 07:08:30 +00:00
Chris Lattner
abff82d99e fix indentation of switch statements, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93106 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 06:59:55 +00:00
Chris Lattner
6091e0289b fix pasto that broke bootstrap.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93105 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 06:50:04 +00:00
Chris Lattner
9e390ddf91 simplify CanEvaluateZExtd now that we don't care about the number of
bits known clear in the result and don't care about the # casts 
eliminated.  TD is also dead but keeping it for now.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93098 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 02:50:04 +00:00
Chris Lattner
5324d80283 two changes:
1) don't try to optimize a sext or zext that is only used by a trunc, let
   the trunc get optimized first.  This avoids some pointless effort in
   some common cases since instcombine scans down a block in the first pass.
2) Change the cost model for zext elimination to consider an 'and' cheaper
   than a zext.  This allows us to do it more aggressively, and for the next
   patch to simplify the code quite a bit.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93097 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 02:39:31 +00:00
Chris Lattner
d26c9e183e enhance CanEvaluateZExtd to handle shift left and sext, allowing
more expressions to be promoted and casts eliminated.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93096 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 02:22:12 +00:00
Chris Lattner
3f7dc880c4 remove an xform subsumed by EvaluateInDifferentType.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93095 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 01:35:55 +00:00
Chris Lattner
4f37978b90 clean up this xform by using m_Trunc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93092 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 01:04:31 +00:00
Chris Lattner
d84dfa43f2 inline and remove the rest of commonIntCastTransforms.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93091 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-10 01:00:46 +00:00