Commit Graph

164 Commits

Author SHA1 Message Date
Dan Gohman 05e8973559 Generalize createSCEV to be able to form SCEV expressions from
ConstantExprs.

llvm-svn: 52615
2008-06-22 19:56:46 +00:00
Dan Gohman be928e3b21 Move LSR's private isZero function to a public SCEV member
function, and make use of it in several places.

llvm-svn: 52463
2008-06-18 16:23:07 +00:00
Nick Lewycky ed169d531d Crash less. The i64 restriction in BinomialCoefficient caused some problems
with code that was expecting different bit widths for different values.

Make getTruncateOrZeroExtend a method on ScalarEvolution, and use it.

llvm-svn: 52248
2008-06-13 04:38:55 +00:00
Nick Lewycky 3195b393d6 Don't treat values as signed when looking at loop steppings in HowForToNonZero.
llvm-svn: 51560
2008-05-25 23:43:32 +00:00
Dan Gohman d78c400b5b Clean up the use of static and anonymous namespaces. This turned up
several things that were neither in an anonymous namespace nor static
but not intended to be global.

llvm-svn: 51017
2008-05-13 00:00:25 +00:00
Nick Lewycky f0bdd22ffd Fix typo and indentation.
llvm-svn: 50706
2008-05-06 04:03:18 +00:00
Dale Johannesen 6145727b43 (re)fix handling of UGT. Pointed out by Nick Lewycky.
llvm-svn: 49991
2008-04-20 16:58:57 +00:00
Chris Lattner 3b18762f40 Switch to using Simplified ConstantFP::get API.
llvm-svn: 49977
2008-04-20 00:41:09 +00:00
Dale Johannesen ce9dc86994 Fix a scalar evolution bug. Reversing everything
does not work because of 0; 2>0 but -2U is also >0.

llvm-svn: 49928
2008-04-18 21:38:31 +00:00
Dan Gohman 5e6ce7bb33 In the special case, call the comparison function instead of
manually performing the comparison. This allows the special
case to work correctly even in the case where someone is
experimenting with a different comparison function :-).

llvm-svn: 49670
2008-04-14 18:23:56 +00:00
Devang Patel 80e43fa744 Restore isCFGOnly property of various analysis passes.
llvm-svn: 48579
2008-03-20 02:25:21 +00:00
Devang Patel 718da668ab PassInfo keep tracks whether a pass is an analysis pass or not.
llvm-svn: 48554
2008-03-19 21:56:59 +00:00
Evan Cheng 01d6257e81 Temporarily reverting 46959.
llvm-svn: 47542
2008-02-25 03:57:32 +00:00
Nick Lewycky 5a3db1406a Simplify this code, no functionality change.
llvm-svn: 47434
2008-02-21 09:14:53 +00:00
Nick Lewycky 839adb877a GlobalValues are Constants, remove redundant code. Also fix typo in a comment.
llvm-svn: 47433
2008-02-21 08:34:02 +00:00
Anton Korobeynikov 579f07135a Unbreak build with gcc 4.3: provide missed includes and silence most annoying warnings.
llvm-svn: 47367
2008-02-20 11:08:44 +00:00
Nick Lewycky b0a2f9513f Use getConstant for ConstantInts.
llvm-svn: 47361
2008-02-20 06:58:55 +00:00
Nick Lewycky 1c44ebcf86 Add 'umax' similar to 'smax' SCEV. Closes PR2003.
Parse reversed smax and umax as smin and umin and express them with negative
or binary-not SCEVs (which are really just subtract under the hood).

Parse 'xor %x, -1' as (-1 - %x).

Remove dead code (ConstantInt::get always returns a ConstantInt).

Don't use getIntegerSCEV(-1, Ty). The first value is an int, then it gets
passed into a uint64_t. Instead, create the -1 directly from
ConstantInt::getAllOnesValue().

llvm-svn: 47360
2008-02-20 06:48:22 +00:00
Wojciech Matyjewicz 0e411f653c Fix typo. Thanks to Duncan for noticing.
llvm-svn: 47062
2008-02-13 12:21:32 +00:00
Wojciech Matyjewicz 35545fd84d Add comments as per review feedback.
llvm-svn: 47061
2008-02-13 11:51:34 +00:00
Wojciech Matyjewicz 1d2c27b23e Fix PR2002. Suppose n is the initial value for the induction
variable (with step 1) and m is its final value. Then, the correct trip 
count is SMAX(m,n)-n. Previously, we used SMAX(0,m-n), but m-n may 
overflow and can't in general be interpreted as signed.

Patch by Nick Lewycky.

llvm-svn: 47007
2008-02-12 15:09:36 +00:00
Wojciech Matyjewicz adae053b53 If the LHS of the comparison is a loop-invariant we also want to move it
to the RHS. This simple change allows to compute loop iteration count 
for loops with condition similar to the one in the testcase (which seems 
to be quite common).

llvm-svn: 46959
2008-02-11 18:37:34 +00:00
Wojciech Matyjewicz d2d9764cc8 Fix PR1798 - an error in the evaluation of SCEVAddRecExpr at an
arbitrary iteration.

The patch:
1) changes SCEVSDivExpr into SCEVUDivExpr,
2) replaces PartialFact() function with BinomialCoefficient(); the 
computations (essentially, the division) in BinomialCoefficient() are 
performed with the apprioprate bitwidth necessary to avoid overflow; 
unsigned division is used instead of the signed one.

Computations in BinomialCoefficient() require support from the code 
generator for APInts. Currently, we use a hack rounding up the 
neccessary bitwidth to the nearest power of 2. The hack is easy to turn 
off in future.

One remaining issue: we assume the divisor of the binomial coefficient 
formula can be computed accurately using 16 bits. It means we can handle 
AddRecs of length up to 9. In future, we should use APInts to evaluate 
the divisor.

Thanks to Nicholas for cooperation!

llvm-svn: 46955
2008-02-11 11:03:14 +00:00
Dan Gohman a65951fef0 Avoid unnecessarily casting away const, fixing a FIXME.
llvm-svn: 46591
2008-01-31 01:05:10 +00:00
Nick Lewycky d1200b00dc Don't be rude, emit debugging info where asked to.
llvm-svn: 45485
2008-01-02 02:49:20 +00:00
Chris Lattner f3ebc3f3d2 Remove attribution from file headers, per discussion on llvmdev.
llvm-svn: 45418
2007-12-29 20:36:04 +00:00
Chris Lattner d2265b45ae Fix PR1850 by removing an unsafe transformation from VMCore/ConstantFold.cpp.
Reimplement the xform in Analysis/ConstantFolding.cpp where we can use
targetdata to validate that it is safe.  While I'm in there, fix some const
correctness issues and generalize the interface to the "operand folder".

llvm-svn: 44817
2007-12-10 22:53:04 +00:00
Nick Lewycky cdb7e54ca7 Add new SCEV, SCEVSMax. This allows LLVM to analyze do-while loops.
llvm-svn: 44319
2007-11-25 22:41:31 +00:00
Chris Lattner 69ec1ec86a simplify some code.
llvm-svn: 44295
2007-11-23 22:36:49 +00:00
Chris Lattner a8fbde3f78 Fix a bug where we'd try to find a scev value for a bitcast operand,
even though the bitcast operand did not have integer type.  This fixes
PR1814.

llvm-svn: 44286
2007-11-23 08:46:22 +00:00
Nick Lewycky 3783b46f9e Instead of calculating constant factors, calculate the number of trailing
bits. Patch from Wojciech Matyjewicz.

llvm-svn: 44268
2007-11-22 07:59:40 +00:00
Nick Lewycky 74a26e3750 Small cleanup. Use APInt::getHighBitsSet method instead of shift left.
"setcc" -> "icmp op" in comments. No functionality change.

llvm-svn: 44249
2007-11-20 08:44:50 +00:00
Nick Lewycky 5b18bd3368 Be more careful when transforming | to +. Patch from Wojciech Matyjewicz.
llvm-svn: 44248
2007-11-20 08:24:44 +00:00
Anton Korobeynikov 6a7ddfdb8f Reverted r44163 per request
llvm-svn: 44177
2007-11-15 18:33:16 +00:00
Nick Lewycky fbb24817cc Fix handling of overflow in loop calculation by adding new UDiv SCEV. This SCEV
is disabled in the sense that it will refuse to create one from a UDiv
instruction, until the code is better tested.

llvm-svn: 44163
2007-11-15 06:30:50 +00:00
Dan Gohman a37eaf2bf9 Move the SCEV object factors from being static members of the individual
SCEV subclasses to being non-static member functions of the ScalarEvolution
class.

llvm-svn: 43224
2007-10-22 18:31:58 +00:00
Nick Lewycky 3934961878 Build the correct range for loops with unusual bounds. Fix from Jay Foad.
llvm-svn: 42394
2007-09-27 14:12:54 +00:00
Dale Johannesen bed9dc423c Next round of APFloat changes.
Use APFloat in UpgradeParser and AsmParser.
Change all references to ConstantFP to use the
APFloat interface rather than double.  Remove
the ConstantFP double interfaces.
Use APFloat functions for constant folding arithmetic
and comparisons.
(There are still way too many places APFloat is
just a wrapper around host float/double, but we're
getting there.)

llvm-svn: 41747
2007-09-06 18:13:44 +00:00
Devang Patel b5933bbbd5 Use SmallVector instead of std::vector.
llvm-svn: 41207
2007-08-21 00:31:24 +00:00
Nick Lewycky 96606cec20 Let scalar-evolution analyze loops with an unsigned comparison for the exit
condition. Fixes 1597.

llvm-svn: 40867
2007-08-06 19:21:00 +00:00
Nick Lewycky b9819f3a8b Don't assume it's safe to transform a loop just because it's dominated by any
comparison. Fixes bug 1598.

llvm-svn: 40866
2007-08-06 18:33:46 +00:00
Nick Lewycky 5246026c8c Handle decrementing loops properly. Fixes PR1533.
Always pass the constant as the second parameter to HowManyLessThans.

Remove obsolete "isSigned" parameter.

llvm-svn: 39893
2007-07-16 02:08:00 +00:00
Dan Gohman 0a76e7f678 Move the APInt form of SCEVUnknown::getIntegerSCEV to SCEVConstant::get, and
use SCEVConstant::get instead of SCEVUnknown::get when constructing a SCEV
for a ConstantInt.

llvm-svn: 38457
2007-07-09 15:25:17 +00:00
Dan Gohman 32f53bbd85 Rename ScalarEvolution::deleteInstructionFromRecords to
deleteValueFromRecords and loosen the types to all it to accept
Value* instead of just Instruction*, since this is what
ScalarEvolution uses internally anyway. This allows more flexibility
for future uses.

llvm-svn: 37657
2007-06-19 14:28:31 +00:00
Dan Gohman eed125f315 In SCEVAddExpr::get, skip over any cast operands before looking for nested
add operands after constant operands. The recent change to recognize
sign-extend expressions caused this to be exposed more often.

llvm-svn: 37628
2007-06-18 19:30:09 +00:00
Dan Gohman cb9e09ad57 Add a SCEV class and supporting code for sign-extend expressions.
This created an ambiguity for expandInTy to decide when to use
sign-extension or zero-extension, but it turns out that most of its callers
don't actually need a type conversion, now that LLVM types don't have
explicit signedness. Drop expandInTy in favor of plain expand, and change
the few places that actually need a type conversion to do it themselves.

llvm-svn: 37591
2007-06-15 14:38:12 +00:00
Nick Lewycky df543f4b84 Optimize this test. Firstly, only Instructions may use other Instructions.
Secondly, checking whether removal succeeded tells you whether it was in
the map to begin with.

llvm-svn: 37469
2007-06-06 11:26:20 +00:00
Nick Lewycky 3e84212897 Fix PR1487 and Transforms/IndVar/2007-06-06-DeleteDanglesPtr.ll
llvm-svn: 37459
2007-06-06 04:12:20 +00:00
Devang Patel 8c78a0bff0 Drop 'const'
llvm-svn: 36662
2007-05-03 01:11:54 +00:00
Devang Patel e95c6ad802 Use 'static const char' instead of 'static const int'.
Due to darwin gcc bug, one version of darwin linker coalesces
static const int, which defauts PassID based pass identification.

llvm-svn: 36652
2007-05-02 21:39:20 +00:00