Commit Graph

4197 Commits

Author SHA1 Message Date
Matthijs Kooijman e92e18be5a Move FindScalarValue from InstructionCombining.cpp to ValueTracking.cpp. While
I'm at it, rename it to FindInsertedValue.

The only functional change is that newly created instructions are no longer
added to instcombine's worklist, but that is not really necessary anyway (and
I'll commit some improvements next that will completely remove the need).

llvm-svn: 52315
2008-06-16 12:48:21 +00:00
Chris Lattner 1c9922703f Fix the crash on SimplifyLibCalls/2005-05-20-sprintf-crash.ll
llvm-svn: 52295
2008-06-16 04:10:21 +00:00
Chris Lattner a88cd4ea2a Fix a case where tailcallelim wouldn't set the changed bit when it made a change.
llvm-svn: 52267
2008-06-14 00:49:48 +00:00
Eli Friedman 5de0a77a9b Don't skip over instructions other than loads that might read memory
when trying to sink stores.

llvm-svn: 52259
2008-06-13 22:02:12 +00:00
Dan Gohman 9ad8c54aab Protect ChangeCompareStride from situations in which it is possible
for it to generate use-before-def IR, such as in this testcase.

llvm-svn: 52258
2008-06-13 21:43:41 +00:00
Eli Friedman 9833a1b407 Make sure SimplifyStoreAtEndOfBlock doesn't mess with loops; the
structure checks are incorrect if the blocks aren't distinct.
Fixes PR2435.

llvm-svn: 52257
2008-06-13 21:17:49 +00:00
Wojciech Matyjewicz 25a7f5de92 Use recently added getTruncateOrZeroExtend method to make the code shorter.
llvm-svn: 52251
2008-06-13 17:02:03 +00:00
Gabor Greif 431e9560b7 fix a minor deviation from the original in my previous commit
llvm-svn: 52247
2008-06-12 21:51:29 +00:00
Gabor Greif f6d8e77027 op_iterator-ify some loops, low hanging fruit only, there is more
llvm-svn: 52246
2008-06-12 21:37:33 +00:00
Evan Cheng 89553cc42e Do not speculatively execute an instruction by hoisting it to its predecessor BB if any of its operands are defined but not used in BB. The transformation will prevent the operand from being sunk into the use block.
llvm-svn: 52244
2008-06-12 21:15:59 +00:00
Evan Cheng 70fe16353a Revert 52223.
llvm-svn: 52243
2008-06-12 20:55:39 +00:00
Owen Anderson accdca1b03 Switch GVN to use ScopedHashTable.
llvm-svn: 52242
2008-06-12 19:25:32 +00:00
Gabor Greif 0babc61631 op_iterator-ify some loops, fix 80col violations
llvm-svn: 52226
2008-06-11 21:38:51 +00:00
Evan Cheng 933c743042 For now, avoid generating FP select instructions in order to speculatively execute integer arithmetic instructions. FP selects are more likely to be expensive (even compared to branch on fcmp). This is not a wonderful solution but I rather err on the side of conservative.
This fixes the heapsort performance regressions.

llvm-svn: 52224
2008-06-11 19:18:20 +00:00
Evan Cheng f3c2902ead Avoid duplicating loop header which leads to unnatural loops (and just seem like general badness to me, likely to cause code explosion).
Patch by Florian Brandner.

llvm-svn: 52223
2008-06-11 19:07:54 +00:00
Matthijs Kooijman b2fc72bfbf Teach instruction combining about the extractvalue. It can succesfully fold
useless insert-extract chains, similar to how it folds them for vectors.

Add a testcase for this.

llvm-svn: 52217
2008-06-11 14:05:05 +00:00
Matthijs Kooijman 3453c7bcb5 Clarify a comment.
llvm-svn: 52212
2008-06-11 09:00:12 +00:00
Gabor Greif 945f2f7fed op_iterator-ify loops
llvm-svn: 52191
2008-06-10 22:03:26 +00:00
Chris Lattner 9c9f531a47 lower calls to abs to inline code, PR2337
llvm-svn: 52138
2008-06-09 08:26:51 +00:00
Chris Lattner dbd595f22d Fix PR2411, where ip constant prop would propagate the
result of a weak function.

llvm-svn: 52137
2008-06-09 07:58:07 +00:00
Duncan Sands 11dd424539 Remove comparison methods for MVT. The main cause
of apint codegen failure is the DAG combiner doing
the wrong thing because it was comparing MVT's using
< rather than comparing the number of bits.  Removing
the < method makes this mistake impossible to commit.
Instead, add helper methods for comparing bits and use
them.

llvm-svn: 52098
2008-06-08 20:54:56 +00:00
Chris Lattner b4866ef30c Limit the icmp+phi merging optimization to the cases where it is profitable:
don't make i1 phis when it won't be possible to eliminate them.

llvm-svn: 52097
2008-06-08 20:52:11 +00:00
Evan Cheng 89200c9177 Speculatively execute a block when the the block is the then part of a triangle shape and it contains a single, side effect free, cheap instruction. The branch is eliminated by adding a select instruction. i.e.
Turn                                                                                                                                                                                                       
BB:                                                                                                                                                                                                        
    %t1 = icmp                                                                                                                                                                                             
    br i1 %t1, label %BB1, label %BB2                                                                                                                                                                      
BB1:                                                                                                                                                                                                       
    %t3 = add %t2, c                                                                                                                                                                                       
    br label BB2                                                                                                                                                                                           
BB2:                                                                                                                                                                                                       
=>                                                                                                                                                                                                         
BB:                                                                                                                                                                                                        
    %t1 = icmp                                                                                                                                                                                             
    %t4 = add %t2, c                                                                                                                                                                                       
    %t3 = select i1 %t1, %t2, %t3

llvm-svn: 52073
2008-06-07 08:52:29 +00:00
Devang Patel 8549e4ca07 LoopSimplify preserves AA.
llvm-svn: 52053
2008-06-06 17:50:58 +00:00
Duncan Sands 13237ac3b9 Wrap MVT::ValueType in a struct to get type safety
and better control the abstraction.  Rename the type
to MVT.  To update out-of-tree patches, the main
thing to do is to rename MVT::ValueType to MVT, and
rewrite expressions like MVT::getSizeInBits(VT) in
the form VT.getSizeInBits().  Use VT.getSimpleVT()
to extract a MVT::SimpleValueType for use in switch
statements (you will get an assert failure if VT is
an extended value type - these shouldn't exist after
type legalization).
This results in a small speedup of codegen and no
new testsuite failures (x86-64 linux).

llvm-svn: 52044
2008-06-06 12:08:01 +00:00
Zhou Sheng 1152ca9101 As Chris suggested, handle the situation if ShAmt larger than BitWidth,
otherwise, opt might crash.

llvm-svn: 52041
2008-06-06 08:32:05 +00:00
Zhou Sheng fbe1dc240c If BitWidth equals to ShtAmt, the RHSKnownZero[BitWidth-ShiftAmt-1] will
crash the opt. Just fix this.

Test case in llvm/test/Transforms/InstCombine/2008-06-05-ashr-crash.ll

llvm-svn: 52003
2008-06-05 14:23:44 +00:00
Matthijs Kooijman 812989b147 Learn ScalarReplAggregrates how stores and loads of first class aggregrates
work and how to replace them into individual values. Also, when trying to
replace an aggregrate that is used by load or store with a single (large)
integer, don't crash (but don't replace the aggregrate either).

Also adds a testcase for both structs and arrays.

llvm-svn: 51997
2008-06-05 12:51:53 +00:00
Matthijs Kooijman e0c5adc158 Let StructRetPromotion check if all if its users are really calls or invokesn,
not other instructions. This fixes a crash with the added testcase.

llvm-svn: 51992
2008-06-05 08:57:20 +00:00
Matthijs Kooijman 463f86639d Let StructRetPromotion check if it's users are really calling it and not
passing its pointer. Fixes test with added testcase.

llvm-svn: 51991
2008-06-05 08:48:32 +00:00
Matthijs Kooijman 230d6fbfeb Use use_iterator::getOperandNo instead of CallSite::hasArgument to check if a
function is passed as an argument instead of called. Also do this check a bit
earlier.

llvm-svn: 51990
2008-06-05 08:34:25 +00:00
Matthijs Kooijman 5afc2740b7 Update comments and documentation to reflect that GCSE and ValueNumbering are
deprecated by the GVN and GVNPRE passes.

llvm-svn: 51983
2008-06-05 07:55:49 +00:00
Owen Anderson 61c7f2a633 Remove unneeded #include.
llvm-svn: 51955
2008-06-04 18:28:10 +00:00
Matthijs Kooijman 2353f35989 Replace two manual loops with calls to CallSite::hasArguments (no functional changes).
llvm-svn: 51947
2008-06-04 16:57:50 +00:00
Duncan Sands fc3c489b52 Change packed struct layout so that field sizes
are the same as in unpacked structs, only field
positions differ.  This only matters for structs
containing x86 long double or an apint; it may
cause backwards compatibility problems if someone
has bitcode containing a packed struct with a
field of one of those types.
The issue is that only 10 bytes are needed to
hold an x86 long double: the store size is 10
bytes, but the ABI size is 12 or 16 bytes (linux/
darwin) which comes from rounding the store size
up by the alignment.  Because it seemed silly not
to pack an x86 long double into 10 bytes in a
packed struct, this is what was done.  I now
think this was a mistake.  Reserving the ABI size
for an x86 long double field even in a packed
struct makes things more uniform: the ABI size is
now always used when reserving space for a type.
This means that developers are less likely to
make mistakes.  It also makes life easier for the
CBE which otherwise could not represent all LLVM
packed structs (PR2402).
Front-end people might need to adjust the way
they create LLVM structs - see following change
to llvm-gcc.

llvm-svn: 51928
2008-06-04 08:21:45 +00:00
Owen Anderson 2df82e7cec LoopIndexSplit can sometimes result in cases where a block in its own domfrontier.
Don't crash when we encounter one of these.

llvm-svn: 51915
2008-06-03 18:29:48 +00:00
Dan Gohman 2ad7e7341c Fix whitespace in whitespace-significant pseudocode in a comment.
llvm-svn: 51890
2008-06-03 00:57:21 +00:00
Devang Patel 7314d0ee3c Update dom tree. Fix PR 2372.
llvm-svn: 51887
2008-06-02 22:52:56 +00:00
Chris Lattner a12a6de683 move CannotBeNegativeZero to ValueTracking. Simplify some signbit comparisons.
llvm-svn: 51864
2008-06-02 01:29:46 +00:00
Chris Lattner 965c769b3c move ComputeMaskedBits, MaskedValueIsZero, and ComputeNumSignBits
out of instcombine into a new file in libanalysis.  This also teaches
ComputeNumSignBits about the number of sign bits in a constantint.

llvm-svn: 51863
2008-06-02 01:18:21 +00:00
Owen Anderson 38099c1b6e Fix two issues that Eli Friedman pointed out, where would misoptimized code like:
char a[200];
init(a, a+200);

OR

int a[200];
char* b = (char*)a;
char* c = (char*)a;
foo(b, c);

llvm-svn: 51850
2008-06-01 22:26:26 +00:00
Owen Anderson d071a8708e Don't remove the memcpy when call slot substitution fails.
llvm-svn: 51848
2008-06-01 21:52:16 +00:00
Duncan Sands 0397cd2ec4 When simplifying a call to a bitcast function, tighten up
the conditions for performing the transform when only the
function declaration is available: no longer allow turning
i32 into i64 for example.  Only allow changing between
pointer types, and between pointer types and integers of
the same size.  For return values ptr -> intptr was already
allowed; I added ptr -> ptr and intptr -> ptr while there.
As shown by a recent objc testcase, changing the way
parameters/return values are passed can be fatal when calling
code written in assembler that directly manipulates call
arguments and return values unless the transform has no
impact on the way they are passed at the codegen level.
While it is possible to imagine an ABI that treats integers
of pointer size differently to pointers, I don't think LLVM
supports any so the transform should now be safe while still
being useful.

llvm-svn: 51834
2008-06-01 07:38:42 +00:00
Nick Lewycky 035fe6f716 Peer through sext/zext when looking for not(cmp).
llvm-svn: 51819
2008-05-31 19:01:33 +00:00
Nick Lewycky 26b8cd84b3 Add more i1 optimizations. add, sub, mul, s/udiv on i1 are now simplified away.
llvm-svn: 51817
2008-05-31 17:59:52 +00:00
Nick Lewycky df9242a833 Adding i1 is always Xor.
llvm-svn: 51816
2008-05-31 17:10:28 +00:00
Gabor Greif 5df4326d78 rewrite operand loops to use iterators
llvm-svn: 51789
2008-05-30 21:24:22 +00:00
Owen Anderson 1f59d9937f Since LCSSA switched over to DenseMap, we have to be more careful to avoid iterator invalidation. Fixes PR2385.
llvm-svn: 51777
2008-05-30 17:31:01 +00:00
Matthijs Kooijman 57da7d2308 Use eraseFromParent() instead of doing that manually in two places.
llvm-svn: 51770
2008-05-30 12:35:46 +00:00
Dan Gohman 86ff8536f9 const-ify getOpcode.
llvm-svn: 51698
2008-05-29 19:53:46 +00:00