Commit Graph

827 Commits

Author SHA1 Message Date
Zhou Sheng 0900993ebc Make the "KnownZero ^ TypeMask" computation just once.
llvm-svn: 35276
2007-03-23 03:13:21 +00:00
Zhou Sheng 755f04b5d7 Simplify the code.
llvm-svn: 35275
2007-03-23 02:39:25 +00:00
Reid Spencer b722f2b110 For PR1205:
APInt support for logical operators in visitAnd, visitOr, and visitXor.

Patch by Zhou Sheng.

llvm-svn: 35273
2007-03-22 22:19:58 +00:00
Reid Spencer 4154e732e6 For PR1205:
* APIntify commonIntCastTransforms
* APIntify visitTrunc
* APIntify visitZExt

Patch by Zhou Sheng.

llvm-svn: 35271
2007-03-22 20:56:53 +00:00
Reid Spencer c3e3b8a32f For PR1205:
* Re-enable the APInt version of MaskedValueIsZero.
* APIntify the Comput{Un}SignedMinMaxValuesFromKnownBits functions
* APIntify visitICmpInst.

llvm-svn: 35270
2007-03-22 20:36:03 +00:00
Dan Gohman dcb291faa4 Change uses of Function::front to Function::getEntryBlock for readability.
llvm-svn: 35265
2007-03-22 16:38:57 +00:00
Reid Spencer f40711637f For PR1248:
* Fix some indentation and comments in InsertRangeTest
* Add an "IsSigned" parameter to AddWithOverflow and make it handle signed
  additions. Also, APIntify this function so it works with any bitwidth.
* For the icmp pred ([us]div %X, C1), C2 transforms, exit early if the
  div instruction's RHS is zero.
* Finally, for icmp pred (sdiv %X, C1), -C2, fix an off-by-one error. The
  HiBound needs to be incremented in order to get the range test correct.

llvm-svn: 35247
2007-03-21 23:19:50 +00:00
Zhou Sheng b3949340c8 Simplify isHighOnes().
llvm-svn: 35211
2007-03-20 12:49:06 +00:00
Reid Spencer 6682721316 Make isOneBitSet faster by using APInt::isPowerOf2. Thanks Chris.
llvm-svn: 35194
2007-03-20 00:16:52 +00:00
Reid Spencer cc031a43aa APIntify the isHighOnes utility function.
llvm-svn: 35190
2007-03-19 21:29:50 +00:00
Reid Spencer ef599b0786 Implement isMaxValueMinusOne in terms of APInt instead of uint64_t.
Patch by Sheng Zhou.

llvm-svn: 35188
2007-03-19 21:10:28 +00:00
Reid Spencer 3b93db72b4 Implement isMinValuePlusOne using facilities of APInt instead of uint64_t
Patch by Zhou Sheng.

llvm-svn: 35187
2007-03-19 21:08:07 +00:00
Reid Spencer 129a86792d Implement isOneBitSet in terms of APInt::countPopulation.
llvm-svn: 35186
2007-03-19 21:04:43 +00:00
Reid Spencer 450434ed65 1. Use APInt::getSignBit to reduce clutter (patch by Sheng Zhou)
2. Replace uses of the "isPositive" utility function with APInt::isPositive

llvm-svn: 35185
2007-03-19 20:58:18 +00:00
Reid Spencer 03c31d5bb0 Remove a redundant clause in an if statement.
Patch by Sheng Zhou.

llvm-svn: 35184
2007-03-19 20:47:50 +00:00
Chris Lattner 0741842b3b Implement InstCombine/and-xor-merge.ll:test[12].
Rearrange some code to simplify it now that shifts are binops

llvm-svn: 35145
2007-03-18 22:51:34 +00:00
Zhou Sheng d8c645b0ba ShiftAmt might equal to zero. Handle this situation.
llvm-svn: 35094
2007-03-14 09:07:33 +00:00
Zhou Sheng b912844554 Enable KnownZero/One.clear().
llvm-svn: 35093
2007-03-14 03:21:24 +00:00
Chris Lattner d1bce956b4 ifdef out some dead code.
Fix PR1244 and Transforms/InstCombine/2007-03-13-CompareMerge.ll

llvm-svn: 35082
2007-03-13 14:27:42 +00:00
Zhou Sheng ebe634e662 For expression like
"APInt::getAllOnesValue(ShiftAmt).zextOrCopy(BitWidth)",
to handle ShiftAmt == BitWidth situation, use zextOrCopy() instead of
zext().

llvm-svn: 35080
2007-03-13 06:40:59 +00:00
Zhou Sheng af4341d441 In APInt version ComputeMaskedBits():
1. Ensure VTy, KnownOne and KnownZero have same bitwidth.
  2. Make code more efficient.

llvm-svn: 35078
2007-03-13 02:23:10 +00:00
Reid Spencer 1791f23803 Add an APInt version of SimplifyDemandedBits.
Patch by Zhou Sheng.

llvm-svn: 35064
2007-03-12 17:25:59 +00:00
Reid Spencer d9281784be Add an APInt version of ShrinkDemandedConstant.
Patch by Zhou Sheng.

llvm-svn: 35063
2007-03-12 17:15:10 +00:00
Zhou Sheng be171ee5cd Avoid to assert on "(KnownZero & KnownOne) == 0".
llvm-svn: 35062
2007-03-12 16:54:56 +00:00
Zhou Sheng b3e00c4656 In function ComputeMaskedBits():
1. Replace getSignedMinValue() with getSignBit() for better code readability.
  2. Replace APIntOps::shl() with operator<<= for convenience.
  3. Make APInt construction more effective.

llvm-svn: 35060
2007-03-12 05:44:52 +00:00
Zhou Sheng d1eb3d593e Fix a bug in function ComputeMaskedBits().
llvm-svn: 35027
2007-03-08 15:15:18 +00:00
Zhou Sheng 387d7b1a35 Fix a bug in APIntified ComputeMaskedBits().
llvm-svn: 35022
2007-03-08 05:42:00 +00:00
Reid Spencer bb5741fb02 For PR1205:
Provide an APIntified version of MaskedValueIsZero. This will (temporarily)
cause a "defined but not used" message from the compiler. It will be used
in the next patch in this series.

Patch by Sheng Zhou.

llvm-svn: 35019
2007-03-08 01:52:58 +00:00
Reid Spencer aa69640b10 For PR1205:
Add a new ComputeMaskedBits function that is APIntified. We'll slowly
convert things over to use this version. When its all done, we'll remove
the existing version.

llvm-svn: 35018
2007-03-08 01:46:38 +00:00
Reid Spencer 3939b1a274 Remove an unnecessary if statement and adjust indentation.
llvm-svn: 34939
2007-03-05 23:36:13 +00:00
Chris Lattner fe53cf2459 fix a subtle bug that caused an MSVC warning. Thanks to Jeffc for pointing this out.
llvm-svn: 34920
2007-03-05 00:11:19 +00:00
Chris Lattner 5fdded1d2f Add some simplifications for demanded bits, this allows instcombine to turn:
define i64 @test(i64 %A, i32 %B) {
        %tmp12 = zext i32 %B to i64             ; <i64> [#uses=1]
        %tmp3 = shl i64 %tmp12, 32              ; <i64> [#uses=1]
        %tmp5 = add i64 %tmp3, %A               ; <i64> [#uses=1]
        %tmp6 = and i64 %tmp5, 123              ; <i64> [#uses=1]
        ret i64 %tmp6
}

into:

define i64 @test(i64 %A, i32 %B) {
        %tmp6 = and i64 %A, 123         ; <i64> [#uses=1]
        ret i64 %tmp6
}

This implements Transforms/InstCombine/add2.ll:test1

llvm-svn: 34919
2007-03-05 00:02:29 +00:00
Jeff Cohen b622c11f77 Unbreak VC++ build.
llvm-svn: 34917
2007-03-05 00:00:42 +00:00
Chris Lattner ab2f913b68 simplify some code
llvm-svn: 34914
2007-03-04 23:16:36 +00:00
Chris Lattner 8258b44b22 Speed up -instcombine by 20% by avoiding a particularly expensive passmgr call.
llvm-svn: 34902
2007-03-04 04:27:24 +00:00
Chris Lattner da1d04a057 my recent change caused a failure in a bswap testcase, because it changed
the order that instcombine processed instructions in the testcase.  The end
result is that instcombine finished with:

define i16 @test1(i16 %a) {
        %tmp = zext i16 %a to i32               ; <i32> [#uses=2]
        %tmp21 = lshr i32 %tmp, 8               ; <i32> [#uses=1]
        %tmp5 = shl i32 %tmp, 8         ; <i32> [#uses=1]
        %tmp.upgrd.32 = or i32 %tmp21, %tmp5            ; <i32> [#uses=1]
        %tmp.upgrd.3 = trunc i32 %tmp.upgrd.32 to i16           ; <i16> [#uses=1]
        ret i16 %tmp.upgrd.3
}

which can't get matched as a bswap.

This patch makes instcombine more sophisticated about removing truncating
casts, allowing it to turn this into:

define i16 @test2(i16 %a) {
        %tmp211 = lshr i16 %a, 8
        %tmp52 = shl i16 %a, 8
        %tmp.upgrd.323 = or i16 %tmp211, %tmp52
        ret i16 %tmp.upgrd.323
}

which then matches as bswap.  This fixes bswap.ll and implements
InstCombine/cast2.ll:test[12].  This also implements cast elimination of
add/sub.

llvm-svn: 34870
2007-03-03 05:27:34 +00:00
Chris Lattner 960a543037 add a top-level iteration loop to instcombine. This means that it will never
finish without combining something it is capable of.

llvm-svn: 34865
2007-03-03 02:04:50 +00:00
Chris Lattner b15e2b182f Fix a significant algorithm problem with the instcombine worklist. removing
a value from the worklist required scanning the entire worklist to remove all
entries.  We now use a combination map+vector to prevent duplicates from
happening and prevent the scan.  This speeds up instcombine on a large file
from the llvm-gcc bootstrap from 189.7s to 4.84s in a debug build and from
5.04s to 1.37s in a release build.

llvm-svn: 34848
2007-03-02 21:28:56 +00:00
Chris Lattner 51f5457ad4 minor cleanup
llvm-svn: 34846
2007-03-02 19:59:19 +00:00
Reid Spencer 24f1a0e78f The 64-bit constructor for ConstantInt changes from int64_t to uint64_t.
This caused a warning for construction with -1. Avoid the warning by using
-1ULL instead.

llvm-svn: 34796
2007-03-01 19:33:52 +00:00
Chris Lattner c4d8e7e614 Fix InstCombine/2007-02-23-PhiFoldInfLoop.ll and PR1217
llvm-svn: 34546
2007-02-24 01:03:45 +00:00
Chris Lattner 99c6cf60f1 convert more vectors to smallvectors, 2.8% speedup
llvm-svn: 34333
2007-02-15 22:52:10 +00:00
Chris Lattner af6094fe3f change some vectors to smallvectors. This speeds up instcombine on 447.dealII
by 5%.

llvm-svn: 34332
2007-02-15 22:48:32 +00:00
Chris Lattner 7907e5fe07 switch an std::set to a SmallPtr set, this speeds up instcombine by 9.5%
on 447.dealII

llvm-svn: 34323
2007-02-15 19:41:52 +00:00
Reid Spencer d84d35ba70 For PR1195:
Rename PackedType -> VectorType, ConstantPacked -> ConstantVector, and
PackedTyID -> VectorTyID. No functional changes.

llvm-svn: 34293
2007-02-15 02:26:10 +00:00
Chris Lattner 945e437c65 Generalize TargetData strings, to support more interesting forms of data.
Patch by Scott Michel.

llvm-svn: 34266
2007-02-14 05:52:17 +00:00
Chris Lattner a06a8fd2d7 Eliminate use of ctors that take vectors.
llvm-svn: 34219
2007-02-13 02:10:56 +00:00
Chris Lattner a731513406 stop using methods that take vectors.
llvm-svn: 34205
2007-02-12 22:56:41 +00:00
Chris Lattner 6e0123b17f Simplify code by using value::takename
llvm-svn: 34176
2007-02-11 01:23:03 +00:00
Chris Lattner 83ac5ae9f3 Fix miscompilations of consumer-typeset, telecomm-gsm, and 176.gcc.
llvm-svn: 33902
2007-02-05 05:57:49 +00:00
Chris Lattner 0a28e90f2c fix a miscompilation of 176.gcc
llvm-svn: 33900
2007-02-05 04:09:35 +00:00
Chris Lattner 3e009e8b8f rewrite shift/shift folding, now that types are not signed.
llvm-svn: 33892
2007-02-05 00:57:54 +00:00
Reid Spencer 3f4e6e84dc For PR1163:
Make the Module's dependent library use a std::vector instead of SetVector
adjust #includes in .cpp files because SetVector.h is no longer included.

llvm-svn: 33855
2007-02-04 00:40:42 +00:00
Chris Lattner 6c344e56b1 remove some dead code
llvm-svn: 33845
2007-02-03 23:28:07 +00:00
Reid Spencer 2f34b98cbf Remove dead code and fix indentation per Chris' review comments.
llvm-svn: 33785
2007-02-02 14:41:37 +00:00
Reid Spencer 0d5f9237b6 Use short form of binary operator create functions.
llvm-svn: 33783
2007-02-02 14:08:20 +00:00
Chris Lattner d5fea61d98 bugfix for reid's shift patch.
llvm-svn: 33779
2007-02-02 05:29:55 +00:00
Reid Spencer 2341c22ec7 Changes to support making the shift instructions be true BinaryOperators.
This feature is needed in order to support shifts of more than 255 bits
on large integer types.  This changes the syntax for llvm assembly to
make shl, ashr and lshr instructions look like a binary operator:
   shl i32 %X, 1
instead of
   shl i32 %X, i8 1
Additionally, this should help a few passes perform additional optimizations.

llvm-svn: 33776
2007-02-02 02:16:23 +00:00
Chris Lattner c904205d28 Fix Transforms/InstCombine/2007-02-01-LoadSinkAlloca.ll, a serious code
pessimization where instcombine can sink a load (good for code size) that
prevents an alloca from being promoted by mem2reg (bad for everything).

llvm-svn: 33771
2007-02-01 22:30:07 +00:00
Chris Lattner 416a8939c3 remove temporary vectors.
llvm-svn: 33715
2007-01-31 20:08:52 +00:00
Chris Lattner 4fc18a4cb8 Revert another incorrectly applied chunk, which fixes InstCombine/vec_insert_to_shuffle.ll
llvm-svn: 33705
2007-01-31 18:09:17 +00:00
Chris Lattner f96f4a874c eliminate temporary vectors
llvm-svn: 33693
2007-01-31 04:40:53 +00:00
Chris Lattner aa17576933 Move symbolic constant folding code to libanalysis.
llvm-svn: 33688
2007-01-31 00:53:10 +00:00
Chris Lattner 024f4ab383 Adjust #includes to match movement of constant folding code from transformutils to libanalysis.
llvm-svn: 33680
2007-01-30 23:46:24 +00:00
Chris Lattner e3eda25641 pass TD to constant folding apis
llvm-svn: 33674
2007-01-30 23:16:15 +00:00
Chris Lattner 2b15f2ba9d remove some bits that are not yet meant to land.
llvm-svn: 33666
2007-01-30 22:50:32 +00:00
Chris Lattner 4284f6463a Symbolically evaluate constant expressions like &A[123] - &A[4].f.
This occurs in C++ code like:

#include <iostream>
#include <iterator>
int a[] = { 1, 2, 3, 4, 5 };
int main() {
  using namespace std;
  copy(a, a + sizeof(a)/sizeof(a[0]), ostream_iterator<int>(cout, "\n"));
  return 0;
}

Before we would decide the loop trip count is:
sdiv (i32 sub (i32 ptrtoint (i32* getelementptr ([5 x i32]* @a, i32 0, i32 5) to i32), i32 ptrtoint ([5 x i32]* @a to i32)), i32 4)

Now we decide it is "5".  Amazing.

This code will need to be refactored, but I'm doing that as a separate
commit.

llvm-svn: 33665
2007-01-30 22:32:46 +00:00
Reid Spencer 5301e7c605 For PR1136: Rename GlobalVariable::isExternal as isDeclaration to avoid
confusion with external linkage types.

llvm-svn: 33663
2007-01-30 20:08:39 +00:00
Chris Lattner c8fb6de78c Fix test/Transforms/InstCombine/2007-01-27-AndICmp.ll, a miscompilation of
Mozilla that Anton tracked down.

llvm-svn: 33591
2007-01-27 23:08:34 +00:00
Reid Spencer 31a4ef4dc1 Cleanup checks in the load and store of casted pointer transforms. Two
changes: (1) don't special case for i1 any more, (2) use the new
TargetData::getTypeSizeInBits method to ensure source and dest are the
same bit width.

llvm-svn: 33427
2007-01-22 05:51:25 +00:00
Reid Spencer 9a4bed06dd Revise the store V, (cast P) -> store (cast V) -> P transform.
We only want to do this if the src and destination types have the same
bit width. This patch uses TargetData::getTypeSizeInBits() instead of
making a special case for integer types and avoiding the transform if
they don't match.

llvm-svn: 33414
2007-01-20 23:35:48 +00:00
Chris Lattner 50ee0e40e5 Teach TargetData to handle 'preferred' alignment for each target, and use
these alignment amounts to align scalars when we can.  Patch by Scott Michel!

llvm-svn: 33409
2007-01-20 22:35:55 +00:00
Reid Spencer e928a15c9e For this transform: store V, (cast P) -> store (cast V), P
don't allow the transform if V and the pointer's element type are different
width integer types.

llvm-svn: 33371
2007-01-19 21:20:31 +00:00
Reid Spencer a94d394ad2 For PR1043:
This is the final patch for this PR. It implements some minor cleanup
in the use of IntegerType, to wit:
1. Type::getIntegerTypeMask -> IntegerType::getBitMask
2. Type::Int*Ty changed to IntegerType* from Type*
3. ConstantInt::getType() returns IntegerType* now, not Type*

This also fixes PR1120.

Patch by Sheng Zhou.

llvm-svn: 33370
2007-01-19 21:13:56 +00:00
Chris Lattner 120ab038eb Fix InstCombine/2007-01-18-VectorInfLoop.ll, a case where instcombine
infinitely loops.

llvm-svn: 33343
2007-01-18 22:16:33 +00:00
Reid Spencer c050af9126 Clean up some code around the store V, (cast P) -> store (cast V), P
transform. Change some variable names so it is clear what is source and
what is dest of the cast. Also, add an assert to ensure that the integer
to integer case is asserting if the bitwidths are different. This prevents
illegal casts from being formed and catches bitwidth bugs sooner.

llvm-svn: 33337
2007-01-18 18:54:33 +00:00
Chris Lattner 479a9fc492 Fix a regression in my isIntegral patch that broke 471.omnetpp. This is
because TargetData::getTypeSize() returns the same for i1 and i8.  This fix
is not right for the full generality of bitwise types, but it fixes the
regression.

llvm-svn: 33237
2007-01-15 17:55:20 +00:00
Chris Lattner c8dcede292 Implement InstCombine/phi.ll:test7, deletion of trivial value loops for
induction variables.

llvm-svn: 33234
2007-01-15 07:30:06 +00:00
Chris Lattner 27df1db485 simplify some code now that types are signless
llvm-svn: 33232
2007-01-15 07:02:54 +00:00
Chris Lattner a4beeef76c delete stores to allocas with one use. This is a trivial form of DSE which
often kicks in for ?: expressions.

llvm-svn: 33231
2007-01-15 06:51:56 +00:00
Chris Lattner 03c4953cdd rename Type::isIntegral to Type::isInteger, eliminating the old Type::isInteger.
rename Type::getIntegralTypeMask to Type::getIntegerTypeMask.

This makes naming much more consistent.  For example, there are now no longer any
instances of IntegerType that are not considered isInteger! :)

llvm-svn: 33225
2007-01-15 02:27:26 +00:00
Chris Lattner 1942249c5b Eliminate calls to isInteger, generalizing code and tightening checks as needed.
llvm-svn: 33218
2007-01-15 01:55:30 +00:00
Chris Lattner 6ee923f3bb instcombine has always been miscompiling fcmp x, x, disregarding possible
NANs.  This fixes PR1111 and Transforms/InstCombine/2007-01-14-FcmpSelf.ll

llvm-svn: 33208
2007-01-14 19:42:17 +00:00
Chris Lattner 387bf3f700 Fix Transforms/InstCombine/2007-01-13-ExtCompareMiscompile.ll, which is part
of PR1107

llvm-svn: 33185
2007-01-13 23:11:38 +00:00
Reid Spencer 7a9c62baa6 For PR1064:
Implement the arbitrary bit-width integer feature. The feature allows
integers of any bitwidth (up to 64) to be defined instead of just 1, 8,
16, 32, and 64 bit integers.

This change does several things:
1. Introduces a new Derived Type, IntegerType, to represent the number of
   bits in an integer. The Type classes SubclassData field is used to
   store the number of bits. This allows 2^23 bits in an integer type.
2. Removes the five integer Type::TypeID values for the 1, 8, 16, 32 and
   64-bit integers. These are replaced with just IntegerType which is not
   a primitive any more.
3. Adjust the rest of LLVM to account for this change.

Note that while this incremental change lays the foundation for arbitrary
bit-width integers, LLVM has not yet been converted to actually deal with
them in any significant way. Most optimization passes, for example, will
still only deal with the byte-width integer types.  Future increments
will rectify this situation.

llvm-svn: 33113
2007-01-12 07:05:14 +00:00
Reid Spencer cddc9dfe97 Implement review feedback for the ConstantBool->ConstantInt merge. Chris
recommended that getBoolValue be replaced with getZExtValue and that
get(bool) be replaced by get(const Type*, uint64_t). This implements
those changes.

llvm-svn: 33110
2007-01-12 04:24:46 +00:00
Reid Spencer 542964f55b Rename BoolTy as Int1Ty. Patch by Sheng Zhou.
llvm-svn: 33076
2007-01-11 18:21:29 +00:00
Zhou Sheng bd23db9968 Remove unnecessary boolean type check.
llvm-svn: 33075
2007-01-11 14:38:17 +00:00
Zhou Sheng 75b871fb1e For PR1043:
Merge ConstantIntegral and ConstantBool into ConstantInt.
Remove ConstantIntegral and ConstantBool from LLVM.

llvm-svn: 33073
2007-01-11 12:24:14 +00:00
Jeff Cohen 223004cd12 Unbreak VC++ build.
llvm-svn: 33021
2007-01-08 20:17:17 +00:00
Reid Spencer 8f166b0ef3 Comparison of primitive type sizes should now be done in bits, not bytes.
This patch converts getPrimitiveSize to getPrimitiveSizeInBits where it is
appropriate to do so (comparison of integer primitive types).

llvm-svn: 33012
2007-01-08 16:32:00 +00:00
Chris Lattner fbc524fe87 relax some types
llvm-svn: 32980
2007-01-07 06:58:05 +00:00
Chris Lattner 7051d758de Fix regressions in InstCombine/call-cast-target.ll and InstCombine/2003-11-13-ConstExprCastCall.ll
llvm-svn: 32959
2007-01-06 19:53:32 +00:00
Chris Lattner c343a99786 this final call to canLosslesslyBitCastTo is dead, because ValueRequiresCast
is only called on integers.

llvm-svn: 32949
2007-01-06 02:11:56 +00:00
Chris Lattner 400f959a0c simplify some more code now that there are not multiple different integer
types of the same size

llvm-svn: 32948
2007-01-06 02:09:32 +00:00
Chris Lattner 64d87b0215 eliminate some uses of canLosslesslyBitCastTo, this actually makes the code stronger, by nuking
relational pointer comparisons with casts.

llvm-svn: 32947
2007-01-06 01:45:59 +00:00
Chris Lattner d7b6ea166d Implement InstCombine/vec_shuffle.ll:%test7, simplifying shuffles with
undef operands.

llvm-svn: 32899
2007-01-05 07:36:08 +00:00
Chris Lattner 17c7c030c2 fold things like a^b != c^a -> b != c. This implements InstCombine/xor.ll:test27
llvm-svn: 32893
2007-01-05 03:04:57 +00:00
Chris Lattner 23eb8ec78b Compile X + ~X to -1. This implements Instcombine/add.ll:test34
llvm-svn: 32890
2007-01-05 02:17:46 +00:00
Reid Spencer 6ff3e73db6 Death to useless bitcast instructions!
llvm-svn: 32866
2007-01-04 05:23:51 +00:00
Reid Spencer c635f47d9a For PR950:
This patch replaces signed integer types with signless ones:
1. [US]Byte -> Int8
2. [U]Short -> Int16
3. [U]Int   -> Int32
4. [U]Long  -> Int64.
5. Removal of isSigned, isUnsigned, getSignedVersion, getUnsignedVersion
   and other methods related to signedness. In a few places this warranted
   identifying the signedness information from other sources.

llvm-svn: 32785
2006-12-31 05:48:39 +00:00
Reid Spencer 193df25eb9 For PR1066:
Fix this by ensuring that a bitcast is inserted to do sign switching. This
is only temporarily needed as the merging of signed and unsigned is next
on the SignlessTypes plate.

llvm-svn: 32757
2006-12-24 00:40:59 +00:00
Reid Spencer 910f23f7d7 Shut up some compilers that can't accurately analyze variable usage
correctly and emit "may be used uninitialized" warnings.

llvm-svn: 32756
2006-12-23 19:17:57 +00:00
Reid Spencer 43c77d53ff For PR1065:
Don't allow CmpInst instances to be processed in FoldSelectOpOp because
you can't easily swap their operands.

llvm-svn: 32753
2006-12-23 18:58:04 +00:00
Reid Spencer 266e42b312 For PR950:
This patch removes the SetCC instructions and replaces them with the ICmp
and FCmp instructions. The SetCondInst instruction has been removed and
been replaced with ICmpInst and FCmpInst.

llvm-svn: 32751
2006-12-23 06:05:41 +00:00
Chris Lattner 79a42ac941 Switch over Transforms/Scalar to use the STATISTIC macro. For each statistic
converted, we lose a static initializer.  This also allows GCC to emit warnings
about unused statistics.

llvm-svn: 32690
2006-12-19 21:40:18 +00:00
Reid Spencer 668d90f289 Convert the last uses of CastInst::createInferredCast to a normal cast
creation. These changes are still temporary but at least this pushes
knowledge of signedness out closer to where it can be determined properly
and allows signedness to be removed from VMCore.

llvm-svn: 32654
2006-12-18 08:47:13 +00:00
Reid Spencer 74a528b427 Fix a bug in EvaluateInDifferentType. The type of operand should not be
used to determine whether a ZExt or SExt cast is performed. Instead, pass
an "isSigned" bool to the function and determine its value from the opcode
of the cast involved.
Also, clean up some cruft from previous patches.

llvm-svn: 32548
2006-12-13 18:21:21 +00:00
Reid Spencer 2a499b0b6c Implement review feedback. Most of this has to do with removing unnecessary
cast instructions. A few are bug fixes.

llvm-svn: 32544
2006-12-13 17:19:09 +00:00
Reid Spencer 612683b0d7 For mul transforms, when checking for a cast from bool as either operand,
make sure to also check that it is a zext from bool, not any other cast
operation type.

llvm-svn: 32539
2006-12-13 08:33:33 +00:00
Reid Spencer 799b5bfc71 Fix and/or/xor (cast A), (cast B) --> cast (and/or/xor A, B)
The cast patch introduced the possibility that the wrong cast opcode
could be used and that this transform could trigger on different kinds
of cast operations. This patch rectifies that.

llvm-svn: 32538
2006-12-13 08:27:15 +00:00
Reid Spencer bb65ebf9a1 Replace inferred getCast(V,Ty) calls with more strict variants.
Rename getZeroExtend and getSignExtend to getZExt and getSExt to match
the the casting mnemonics in the rest of LLVM.

llvm-svn: 32514
2006-12-12 23:36:14 +00:00
Chris Lattner 2dc148e89d this can be trunc or bitcast, per line 3092.
llvm-svn: 32487
2006-12-12 19:11:20 +00:00
Chris Lattner ade1f6894d Fix regression on 400.perlbench last night.
llvm-svn: 32486
2006-12-12 18:41:03 +00:00
Reid Spencer 13bc5d7b57 Fix numerous inferred casts.
llvm-svn: 32479
2006-12-12 09:18:51 +00:00
Bill Wendling f3baad3ee1 Changed llvm_ostream et all to OStream. llvm_cerr, llvm_cout, llvm_null, are
now cerr, cout, and NullStream resp.

llvm-svn: 32298
2006-12-07 01:30:32 +00:00
Reid Spencer 4ae56f3086 Update ConstantIntegral Max/Min tests for new interface.
llvm-svn: 32288
2006-12-06 20:39:57 +00:00
Chris Lattner 700b873130 Detemplatize the Statistic class. The only type it is instantiated with
is 'unsigned'.

llvm-svn: 32279
2006-12-06 17:46:33 +00:00
Chris Lattner c209b584eb add an instcombine xform. This speeds up 462.libquantum from 9.78s to
7.48s.  This regression is due to unforseen consequences of the cast patch.

llvm-svn: 32209
2006-12-05 01:26:29 +00:00
Reid Spencer 14fbdd5523 Update call to CastInst::getCastOpcode for its new signature.
llvm-svn: 32166
2006-12-04 02:48:01 +00:00
Chris Lattner 7a002fec1f disable transformations that are invalid for fp vectors. This fixes
Transforms/InstCombine/2006-12-01-BadFPVectorXform.ll

llvm-svn: 32112
2006-12-02 00:13:08 +00:00
Reid Spencer ad05ee9f39 Remove 4 FIXMEs to hack around cast-to-bool problems which no longer exist.
llvm-svn: 32051
2006-11-30 23:13:36 +00:00
Chris Lattner 960acb008b implement cast.ll:test35. With this, we recognize:
unsigned short swp(unsigned short a) {
       return ((a & 0xff00) >> 8 | (a & 0x00ff) << 8);
}

as an idiom for bswap.

llvm-svn: 32011
2006-11-29 07:18:39 +00:00
Chris Lattner d747f015ff Teach instcombine to turn trunc(srl x, c) -> srl (trunc(x), c) when safe.
This implements InstCombine/cast.ll:test34.  It fires hundreds of times on
176.gcc.

llvm-svn: 32009
2006-11-29 07:04:07 +00:00
Chris Lattner a7942b7bbd Implement Regression/Transforms/InstCombine/bswap-fold.ll,
folding   seteq (bswap(x)), c -> seteq(x,bswap(c))

llvm-svn: 32006
2006-11-29 05:02:16 +00:00
Reid Spencer a736fdf216 Join a split line.
llvm-svn: 31996
2006-11-29 01:11:01 +00:00
Reid Spencer 116ad83aa0 Undo the last patch until 253.perlbmk passes with these changes.
llvm-svn: 31977
2006-11-28 20:23:51 +00:00
Reid Spencer 59fe2d89ae Remove 4 FIXME's from the CAST patch now that the back end is correctly
producing code for "trunc to bool". This passes all tests on Linux.

llvm-svn: 31963
2006-11-28 07:23:01 +00:00
Chris Lattner 8e9a7b73d9 Fix PR1014 and InstCombine/2006-11-27-XorBug.ll.
llvm-svn: 31941
2006-11-27 19:55:07 +00:00
Reid Spencer 6c38f0bb07 For PR950:
The long awaited CAST patch. This introduces 12 new instructions into LLVM
to replace the cast instruction. Corresponding changes throughout LLVM are
provided. This passes llvm-test, llvm/test, and SPEC CPUINT2000 with the
exception of 175.vpr which fails only on a slight floating point output
difference.

llvm-svn: 31931
2006-11-27 01:05:10 +00:00
Bill Wendling 5dbf43c983 Removed #include <iostream> and replaced with llvm_* streams.
llvm-svn: 31923
2006-11-26 09:46:52 +00:00
Chris Lattner ec45a4c88c This xform is handled by FoldOpIntoPhi in visitCastInst in a more elegant way.
llvm-svn: 31889
2006-11-21 17:05:13 +00:00
Chris Lattner e3a63d136d Fix a gcc 4.2 warning.
llvm-svn: 31751
2006-11-15 04:53:24 +00:00
Chris Lattner f05d69ae72 implement InstCombine/shift-simplify.ll by transforming:
(X >> Z) op (Y >> Z)  -> (X op Y) >> Z

for all shifts and all ops={and/or/xor}.

llvm-svn: 31729
2006-11-14 07:46:50 +00:00
Chris Lattner d12a4bf799 implement InstCombine/and-compare.ll:test1. This compiles:
typedef struct { unsigned prefix : 4; unsigned code : 4; unsigned unsigned_p : 4; } tree_common;
int foo(tree_common *a, tree_common *b) { return a->code == b->code; }

into:

_foo:
        movl 4(%esp), %eax
        movl 8(%esp), %ecx
        movl (%eax), %eax
        xorl (%ecx), %eax
        # TRUNCATE movb %al, %al
        shrb $4, %al
        testb %al, %al
        sete %al
        movzbl %al, %eax
        ret

instead of:

_foo:
        movl 8(%esp), %eax
        movb (%eax), %al
        shrb $4, %al
        movl 4(%esp), %ecx
        movb (%ecx), %cl
        shrb $4, %cl
        cmpb %al, %cl
        sete %al
        movzbl %al, %eax
        ret

saving one cycle by eliminating a shift.

llvm-svn: 31727
2006-11-14 06:06:06 +00:00
Chris Lattner d4dee405cb Fix InstCombine/2006-11-10-ashr-miscompile.ll a miscompilation introduced
by the shr -> [al]shr patch.  This was reduced from 176.gcc.

llvm-svn: 31653
2006-11-10 23:38:52 +00:00
Chris Lattner 6e2c15c158 Teach ShrinkDemandedConstant how to handle X+C. This implements:
add.ll:test33, add.ll:test34, shift-sra.ll:test2

llvm-svn: 31586
2006-11-09 05:12:27 +00:00
Chris Lattner 4f218d56f5 reenable factoring of GEP expressions, being more precise about the
case that it bad to do.

llvm-svn: 31563
2006-11-08 19:42:28 +00:00
Chris Lattner cd62f11227 make this code more efficient by not creating a phi node we are just going to
delete in the first place.  This also makes it simpler.

llvm-svn: 31562
2006-11-08 19:29:23 +00:00
Chris Lattner a3acfca920 disable this factoring optzn for GEPs for now, this severely pessimizes some
loops.

llvm-svn: 31560
2006-11-08 18:49:31 +00:00
Reid Spencer fdff938a7e For PR950:
This patch converts the old SHR instruction into two instructions,
AShr (Arithmetic) and LShr (Logical). The Shr instructions now are not
dependent on the sign of their operands.

llvm-svn: 31542
2006-11-08 06:47:33 +00:00
Andrew Lenharth 0ebb0b03e6 The wrong parameter was being tested to deturmine i32 vs i64
llvm-svn: 31431
2006-11-03 22:45:50 +00:00
Reid Spencer de46e48420 For PR786:
Turn on -Wunused and -Wno-unused-parameter. Clean up most of the resulting
fall out by removing unused variables. Remaining warnings have to do with
unused functions (I didn't want to delete code without review) and unused
variables in generated code. Maintainers should clean up the remaining
issues when they see them. All changes pass DejaGnu tests and Olden.

llvm-svn: 31380
2006-11-02 20:25:50 +00:00
Reid Spencer 7eb55b395f For PR950:
Replace the REM instruction with UREM, SREM and FREM.

llvm-svn: 31369
2006-11-02 01:53:59 +00:00
Chris Lattner eebea43b48 Factor gep instructions through phi nodes.
llvm-svn: 31346
2006-11-01 07:43:41 +00:00
Chris Lattner 14f82c7dcd Turn a phi of many loads into a phi of the address and a single load of the
result.  This can significantly shrink code and exposes identities more
aggressively.

llvm-svn: 31344
2006-11-01 07:13:54 +00:00
Chris Lattner dc826fc068 Fix a bug in the previous patch
llvm-svn: 31342
2006-11-01 04:55:47 +00:00
Chris Lattner cadac0c5c3 Fold things like "phi [add (a,b), add(c,d)]" into two phi's and one add.
This triggers thousands of times on multisource.

llvm-svn: 31341
2006-11-01 04:51:18 +00:00
Reid Spencer 00c482b7a2 Simplify code a bit by changing instances of:
InsertNewInstBefore(new CastInst(Val, ValTy, Val->GetName()), I)
into:
   InsertCastBefore(Val, ValTy, I)

llvm-svn: 31204
2006-10-26 19:19:06 +00:00
Reid Spencer 7e80b0b31e For PR950:
Make necessary changes to support DIV -> [SUF]Div. This changes llvm to
have three division instructions: signed, unsigned, floating point. The
bytecode and assembler are bacwards compatible, however.

llvm-svn: 31195
2006-10-26 06:15:43 +00:00
Chris Lattner 5dee3b2526 Fix miscompilation of MallocBench/espresso which code review pointed out
but apparently didn't make it into the final patch.

llvm-svn: 31070
2006-10-20 18:20:21 +00:00
Reid Spencer e0fc4dfc22 For PR950:
This patch implements the first increment for the Signless Types feature.
All changes pertain to removing the ConstantSInt and ConstantUInt classes
in favor of just using ConstantInt.

llvm-svn: 31063
2006-10-20 07:07:24 +00:00
Devang Patel 5d417e35bc While creating mask, use 1ULL instead of 1.
llvm-svn: 31062
2006-10-20 01:16:56 +00:00
Devang Patel 5d6df959e3 It is OK to remove extra cast if operation is EQ/NE even though source
and destination sign may not match but other conditions are met.

llvm-svn: 31056
2006-10-19 20:59:13 +00:00
Devang Patel 88afd00d1d Typo Typo.
llvm-svn: 31055
2006-10-19 19:21:36 +00:00
Devang Patel 472530d9fc Typo.
llvm-svn: 31054
2006-10-19 19:05:38 +00:00
Devang Patel b42aef4925 Fix bug in PR454 resolution. Added new test case.
This fixes llvmAsmParser.cpp miscompile by llvm on PowerPC Darwin.

llvm-svn: 31053
2006-10-19 18:54:08 +00:00
Reid Spencer 3c514959dd Undo Chris' last patch, it caused a regression.
llvm-svn: 30991
2006-10-16 23:08:08 +00:00
Chris Lattner 9a1c7dd27a fix a buggy check that accidentally disabled this xform
llvm-svn: 30967
2006-10-15 22:42:15 +00:00
Chris Lattner 2deeaeaca7 add a new SimplifyDemandedVectorElts method, which works similarly to
SimplifyDemandedBits.  The idea is that some operations can be simplified if
not all of the computed elements are needed.  Some targets (like x86) have a
large number of intrinsics that operate on a single element, but pass other
elts through unmodified.  If those other elements are not needed, the
intrinsics can be simplified to scalar operations, and insertelement ops can
be removed.

This turns (f.e.):

ushort %Convert_sse(float %f) {
        %tmp = insertelement <4 x float> undef, float %f, uint 0                ; <<4 x float>> [#uses=1]
        %tmp10 = insertelement <4 x float> %tmp, float 0.000000e+00, uint 1             ; <<4 x float>> [#uses=1]
        %tmp11 = insertelement <4 x float> %tmp10, float 0.000000e+00, uint 2           ; <<4 x float>> [#uses=1]
        %tmp12 = insertelement <4 x float> %tmp11, float 0.000000e+00, uint 3           ; <<4 x float>> [#uses=1]
        %tmp28 = tail call <4 x float> %llvm.x86.sse.sub.ss( <4 x float> %tmp12, <4 x float> < float 1.000000e+00, float 0.000000e+00, float 0.000000e+00, float 0.000000e+00 > )               ; <<4 x float>> [#uses=1]
        %tmp37 = tail call <4 x float> %llvm.x86.sse.mul.ss( <4 x float> %tmp28, <4 x float> < float 5.000000e-01, float 0.000000e+00, float 0.000000e+00, float 0.000000e+00 > )               ; <<4 x float>> [#uses=1]
        %tmp48 = tail call <4 x float> %llvm.x86.sse.min.ss( <4 x float> %tmp37, <4 x float> < float 6.553500e+04, float 0.000000e+00, float 0.000000e+00, float 0.000000e+00 > )               ; <<4 x float>> [#uses=1]
        %tmp59 = tail call <4 x float> %llvm.x86.sse.max.ss( <4 x float> %tmp48, <4 x float> zeroinitializer )          ; <<4 x float>> [#uses=1]
        %tmp = tail call int %llvm.x86.sse.cvttss2si( <4 x float> %tmp59 )              ; <int> [#uses=1]
        %tmp69 = cast int %tmp to ushort                ; <ushort> [#uses=1]
        ret ushort %tmp69
}

into:

ushort %Convert_sse(float %f) {
entry:
        %tmp28 = sub float %f, 1.000000e+00             ; <float> [#uses=1]
        %tmp37 = mul float %tmp28, 5.000000e-01         ; <float> [#uses=1]
        %tmp375 = insertelement <4 x float> undef, float %tmp37, uint 0         ; <<4 x float>> [#uses=1]
        %tmp48 = tail call <4 x float> %llvm.x86.sse.min.ss( <4 x float> %tmp375, <4 x float> < float 6.553500e+04, float undef, float undef, float undef > )           ; <<4 x float>> [#uses=1]
        %tmp59 = tail call <4 x float> %llvm.x86.sse.max.ss( <4 x float> %tmp48, <4 x float> < float 0.000000e+00, float undef, float undef, float undef > )            ; <<4 x float>> [#uses=1]
        %tmp = tail call int %llvm.x86.sse.cvttss2si( <4 x float> %tmp59 )              ; <int> [#uses=1]
        %tmp69 = cast int %tmp to ushort                ; <ushort> [#uses=1]
        ret ushort %tmp69
}

which improves codegen from:

_Convert_sse:
        movss LCPI1_0, %xmm0
        movss 4(%esp), %xmm1
        subss %xmm0, %xmm1
        movss LCPI1_1, %xmm0
        mulss %xmm0, %xmm1
        movss LCPI1_2, %xmm0
        minss %xmm0, %xmm1
        xorps %xmm0, %xmm0
        maxss %xmm0, %xmm1
        cvttss2si %xmm1, %eax
        andl $65535, %eax
        ret

to:

_Convert_sse:
        movss 4(%esp), %xmm0
        subss LCPI1_0, %xmm0
        mulss LCPI1_1, %xmm0
        movss LCPI1_2, %xmm1
        minss %xmm1, %xmm0
        xorps %xmm1, %xmm1
        maxss %xmm1, %xmm0
        cvttss2si %xmm0, %eax
        andl $65535, %eax
        ret


This is just a first step, it can be extended in many ways.  Testcase here:
Transforms/InstCombine/vec_demanded_elts.ll

llvm-svn: 30752
2006-10-05 06:55:50 +00:00
Chris Lattner 7d19067c42 Fix a bug from r1.391 of this file, where we checked the size instead of
the alignment when promoting allocations.  This implements
InstCombine/cast.ll:test32

llvm-svn: 30682
2006-10-01 19:40:58 +00:00
Chris Lattner 6ab03f6a08 Eliminate ConstantBool::True and ConstantBool::False. Instead, provide
ConstantBool::getTrue() and ConstantBool::getFalse().

llvm-svn: 30665
2006-09-28 23:35:22 +00:00
Andrew Lenharth 44cb67af5c simplify
llvm-svn: 30535
2006-09-20 15:37:57 +00:00
Chris Lattner 380c7e9a59 We went through all that trouble to compute whether it was safe to transform
this comparison, but never checked it.  Whoops, no wonder we miscompiled
177.mesa!

llvm-svn: 30511
2006-09-20 04:44:59 +00:00
Evan Cheng cd3f6ff0e5 Back out Chris' last set of changes. This breaks 177.mesa and povray somehow.
llvm-svn: 30505
2006-09-20 01:39:40 +00:00
Evan Cheng 453280b94d 80 col.
llvm-svn: 30504
2006-09-20 01:10:02 +00:00
Andrew Lenharth 4f339bebb0 If we have an add, do it in the pointer realm, not the int realm. This is critical in the linux kernel for pointer analysis correctness
llvm-svn: 30496
2006-09-19 18:24:51 +00:00
Chris Lattner 12f52faf93 implement select.ll:test19-22
llvm-svn: 30482
2006-09-19 06:18:21 +00:00
Chris Lattner de07792595 Fix an infinite loop building the CFE
llvm-svn: 30465
2006-09-18 18:27:05 +00:00
Chris Lattner 4922a0e53f Implement InstCombine/cast.ll:test31. This speeds up 462.libquantum by 26%.
llvm-svn: 30456
2006-09-18 05:27:43 +00:00
Chris Lattner 420c4bcc8d Implement Transforms/InstCombine/shift-sra.ll:test0
llvm-svn: 30450
2006-09-18 04:31:40 +00:00
Chris Lattner b3f24c91b0 Rewrite shift/and/compare sequences to promote better licm of the RHS.
Use isLogicalShift/isArithmeticShift to simplify code.

llvm-svn: 30448
2006-09-18 04:22:48 +00:00
Chris Lattner 850465d53f Fix Transforms/InstCombine/2006-09-15-CastToBool.ll and PR913
llvm-svn: 30405
2006-09-16 03:14:10 +00:00
Chris Lattner d28627009a Fix PR905 and InstCombine/2006-09-11-EmptyStructCrash.ll
llvm-svn: 30266
2006-09-11 21:43:16 +00:00
Chris Lattner 0468987592 Implement Transforms/InstCombine/hoist_instr.ll
llvm-svn: 30234
2006-09-09 22:02:56 +00:00
Chris Lattner d79dc79831 Turn div X, (Cond ? Y : 0) -> div X, Y
This implements select.ll::test18.

llvm-svn: 30230
2006-09-09 20:26:32 +00:00
Chris Lattner c2d3d3112e eliminate RegisterOpt. It does the same thing as RegisterPass.
llvm-svn: 29925
2006-08-27 22:42:52 +00:00
Chris Lattner 3d27be1333 s|llvm/Support/Visibility.h|llvm/Support/Compiler.h|
llvm-svn: 29911
2006-08-27 12:54:02 +00:00
Chris Lattner 091b6ea847 Silence a warning produced in assertions-disabled mode
llvm-svn: 29108
2006-07-11 18:31:26 +00:00
Owen Anderson bbf8990ef7 Add a comment, and fix a typo that broke the build.
llvm-svn: 29094
2006-07-10 22:15:25 +00:00
Owen Anderson ae8aa646f1 Don't indent the entire function.
llvm-svn: 29093
2006-07-10 22:03:18 +00:00
Chris Lattner b7845d69db Recognize 16-bit bswaps by relaxing overconstrained pattern.
This implements Transforms/InstCombine/bswap.ll:test[34].

llvm-svn: 29087
2006-07-10 20:25:24 +00:00
Owen Anderson a6968f83b2 Make instcombine not remove Phi nodes when LCSSA is live.
llvm-svn: 29083
2006-07-10 19:03:49 +00:00
Chris Lattner 4a4c7fe7fa Shrink libllvmgcc.dylib by another 23K
llvm-svn: 28972
2006-06-28 22:08:15 +00:00
Chris Lattner 3fda386965 Fix Transforms/InstCombine/2006-06-28-infloop.ll
llvm-svn: 28961
2006-06-28 17:34:50 +00:00
Andrew Lenharth ebfa24ee9a Catch more function pointer casting problems
Remove the Function pointer cast in these calls, converting it to
a cast of argument.
%tmp60 = tail call int cast (int (ulong)* %str to int (int)*)( int 10 )
%tmp60 = tail call int cast (int (ulong)* %str to int (int)*)( uint %tmp51 )

llvm-svn: 28953
2006-06-28 01:01:52 +00:00
Chris Lattner c482a9e31a Implement Transforms/InstCombine/bswap.ll, turning common shift/and/or bswap
idioms into bswap intrinsics.

llvm-svn: 28803
2006-06-15 19:07:26 +00:00
Chris Lattner 95cebb082f Fix a bug in a recent patch. This fixes UnitTests/Vector/Altivec/casts.c on
PPC/altivec

llvm-svn: 28698
2006-06-06 22:26:02 +00:00
Chris Lattner 1df0e98ac2 Swap the order of operands created here. For +&|^, the order doesn't matter,
but for sub, it really does!  Fix fixes a miscompilation of fibheap_cut in
llvmgcc4.

llvm-svn: 28600
2006-05-31 21:14:00 +00:00
Chris Lattner dab43b2b0e Implement Transforms/InstCombine/store.ll:test2.
llvm-svn: 28503
2006-05-26 19:19:20 +00:00
Chris Lattner 0e47716e69 Transform things like (splat(splat)) -> splat
llvm-svn: 28490
2006-05-26 00:29:06 +00:00
Chris Lattner 12249be286 Introduce a helper function that simplifies interpretation of shuffle masks.
No functionality change.

llvm-svn: 28489
2006-05-25 23:48:38 +00:00
Chris Lattner 99155be33f Turn (cast (shuffle (cast)) -> shuffle (cast) if it reduces the # casts in
the program.  This exposes more opportunities for the instcombiner, and implements
vec_shuffle.ll:test6

llvm-svn: 28487
2006-05-25 23:24:33 +00:00
Chris Lattner 83f6578b0c extract element from a shuffle vector can be trivially turned into an
extractelement from the SV's source.  This implement vec_shuffle.ll:test[45]

llvm-svn: 28485
2006-05-25 22:53:38 +00:00
Chris Lattner d0622b6894 Silence a bogus gcc warning
llvm-svn: 28422
2006-05-20 23:14:03 +00:00
Evan Cheng 18d0438148 Backing out last check-in for now. It's causing an infinite loop gccas lencode.
llvm-svn: 28284
2006-05-14 06:46:03 +00:00
Chris Lattner 3987a8532d Add/Sub/Mul are safe to promote here as well. Incrementing a single-bit
bitfield now gives this code:

_plus:
        lwz r2, 0(r3)
        rlwimi r2, r2, 0, 1, 31
        xoris r2, r2, 32768
        stw r2, 0(r3)
        blr

instead of this:

_plus:
        lwz r2, 0(r3)
        srwi r4, r2, 31
        slwi r4, r4, 31
        addis r4, r4, -32768
        rlwimi r2, r4, 0, 0, 0
        stw r2, 0(r3)
        blr

this can obviously still be improved.

llvm-svn: 28275
2006-05-13 02:16:08 +00:00
Chris Lattner 1ebbe6a22e Implement simple promotion for cast elimination in instcombine. This is
currently very limited, but can be extended in the future.  For example,
we now compile:

uint %test30(uint %c1) {
        %c2 = cast uint %c1 to ubyte
        %c3 = xor ubyte %c2, 1
        %c4 = cast ubyte %c3 to uint
        ret uint %c4
}

to:

_xor:
        movzbl 4(%esp), %eax
        xorl $1, %eax
        ret

instead of:

_xor:
        movb $1, %al
        xorb 4(%esp), %al
        movzbl %al, %eax
        ret

More impressively, we now compile:

struct B { unsigned bit : 1; };
void xor(struct B *b) { b->bit = b->bit ^ 1; }

To (X86/PPC):

_xor:
        movl 4(%esp), %eax
        xorl $-2147483648, (%eax)
        ret
_xor:
        lwz r2, 0(r3)
        xoris r2, r2, 32768
        stw r2, 0(r3)
        blr

instead of (X86/PPC):

_xor:
        movl 4(%esp), %eax
        movl (%eax), %ecx
        movl %ecx, %edx
        shrl $31, %edx
        # TRUNCATE movb %dl, %dl
        xorb $1, %dl
        movzbl %dl, %edx
        andl $2147483647, %ecx
        shll $31, %edx
        orl %ecx, %edx
        movl %edx, (%eax)
        ret

_xor:
        lwz r2, 0(r3)
        srwi r4, r2, 31
        xori r4, r4, 1
        rlwimi r2, r4, 31, 0, 0
        stw r2, 0(r3)
        blr

This implements InstCombine/cast.ll:test30.

llvm-svn: 28273
2006-05-13 02:06:03 +00:00
Chris Lattner 1443bc52be Refactor some code, making it simpler.
When doing the initial pass of constant folding, if we get a constantexpr,
simplify the constant expr like we would do if the constant is folded in the
normal loop.

This fixes the missed-optimization regression in
Transforms/InstCombine/getelementptr.ll last night.

llvm-svn: 28224
2006-05-11 17:11:52 +00:00
Chris Lattner a36ee4ea34 Two changes:
1. Implement InstCombine/deadcode.ll by not adding instructions in unreachable
   blocks (due to constants in conditional branches/switches) to the worklist.
   This causes them to be deleted before instcombine starts up, leading to
   better optimization.

2. In the prepass over instructions, do trivial constprop/dce as we go.  This
   has the effect of improving the effectiveness of #1.  In addition, it
   *significantly* speeds up instcombine on test cases with large amounts of
   constant folding code (for example, that produced by code specialization
   or partial evaluation).  In one example, it speeds up instcombine from
   0.0589s to 0.0224s with a release build (a 2.6x speedup).

llvm-svn: 28215
2006-05-10 19:00:36 +00:00