doing very similar pointer capture analysis.
Factor out the common logic. The new version
is from FunctionAttrs since it does a better
job than the version in BasicAliasAnalysis
llvm-svn: 62461
vector and extraneous loop over it, 2) not delete globals used by
phis/selects etc which could actually be useful. This fixes PR3321.
Many thanks to Duncan for narrowing this down.
llvm-svn: 62201
compensation for turning off gcc's inliner. This gets
us closer to the amount of inlining we were getting before.
It is not a win on everything, of course, but seems to
gain overall.
llvm-svn: 62058
was it not very helpful, it was also wrong! The problem
is shown in the testcase: the alloca might be passed to
a nocapture callee which dereferences it and returns the
original pointer. But because it was a nocapture call we
think we don't need to track its uses, but we do.
llvm-svn: 61876
In fact this also deletes those with linkonce linkage,
however this is currently dead because for the moment
aliases aren't allowed to have this linkage type.
llvm-svn: 61742
not have pointer type. In particular, it may
be the condition argument for a select or a GEP
index. While I was unable to construct a testcase
for which some bits of the original pointer are
captured due to one of these, it's very very close
to being possible - so play safe and exclude these
possibilities.
llvm-svn: 61580
the argument to be stored to an alloca by tracking uses
of the alloca. This occurs 4 times (out of 7121, 0.05%)
in MultiSource/Applications, so may not be worth it. On
the other hand, it is easy to do and fairly cheap. The
functions it helps are: W_addcom and W_addlit in spiff;
process_args (argv) in d (make_dparser); ercPixConcealIMB
in JM/ldecod.
llvm-svn: 61570
functions that don't write can't leak a pointer except through
the return value, so a void readonly function is implicitly nocapture.
Test these, and add a test that verifies that f1 calling f2 with an
otherwise dead pointer gets both of them marked nocapture.
llvm-svn: 61552
to work out (in a very simplistic way) which function
arguments (pointer arguments only) are only dereferenced
and so do not escape. Mark such arguments 'nocapture'.
llvm-svn: 61525
and select instructions doesn't buy anything here
except extra complexity: the only difference in
the entire testsuite was that a readonly function
became readnone in MiBench/consumer-typeset. Add
a comment about this.
llvm-svn: 61478
constants, since doing so is irrelevant for aliasing
purposes. While this doesn't increase the total number
of functions marked readonly or readnone in MultiSource/
Applications (3089), it does result in 12 functions being
marked readnone rather than readonly.
Before:
readnone: 820
readonly: 2269
After:
readnone: 832
readonly: 2257
llvm-svn: 61469
nodes. This allows it to do fairly general phi insertion if a
load from a pointer global wants to be SRAd but the load is used
by (recursive) phi nodes. This fixes a pessimization on ppc
introduced by Load PRE.
llvm-svn: 61123
* merge two weak functions by making them both alias a third non-weak fn
* don't reimplement CallSite::hasArgument
* whitelist the safe linkage types
llvm-svn: 58568
This triggers only 60 times in llvm-test (look at .llvm.bc, not .linked.rbc)
and so it probably wont be turned on by default. Also, may of those are likely
to go away when PR2973 is fixed.
llvm-svn: 58557
function.
- This explicitly models the costs for functions which should
"always" or "never" be inlined. This fixes bugs where such costs
were not previously respected.
llvm-svn: 58450
when deciding whether to mark a function readnone/readonly.
Since the pass is currently run before SROA, this may be
quite helpful. Requested by Chris on IRC.
llvm-svn: 57050
- return attributes - inreg, zext and sext
- parameter attributes
- function attributes - nounwind, readonly, readnone, noreturn
Return attributes use 0 as the index.
Function attributes use ~0U as the index.
This patch requires corresponding changes in llvm-gcc and clang.
llvm-svn: 56704
s/ParamAttr/Attribute/g
s/PAList/AttrList/g
s/FnAttributeWithIndex/AttributeWithIndex/g
s/FnAttr/Attribute/g
This sets the stage
- to implement function notes as function attributes and
- to distinguish between function attributes and return value attributes.
This requires corresponding changes in llvm-gcc and clang.
llvm-svn: 56622
can get the readnone/readonly attributes, and gives them it.
The plan is to remove markmodref (which did the same thing
by querying GlobalsModRef) and delete the analogous
functionality from GlobalsModRef.
llvm-svn: 56341
call (thus changing the call site) it didn't
inform the callgraph about this. But the
call site does matter - as shown by the testcase,
the callgraph become invalid after the inliner
ran (with an edge between two functions simply
missing), resulting in wrong deductions by
GlobalsModRef.
llvm-svn: 55872
because it does not maintain a correct list
of callsites. I discovered (see following
commit) that the inliner will create a wrong
callgraph if it is fed a callgraph with
correct edges but incorrect callsites. These
were created by Prune-EH, and while it wasn't
done via removeCallEdgeTo, it could have been
done via removeCallEdgeTo, which is an accident
waiting to happen. Use removeCallEdgeFor
instead.
llvm-svn: 55859
invalidating the iterator by deleting the current use. This fixes a segfault on
64 bit linux reported in PR2675.
Also remove an unneeded if.
llvm-svn: 54778
that says "unconditional loads from this argument are safe", we now keep track
of the safety per set of indices from which loads happen. This prevents
ArgPromotion from promoting loads that aren't really valid. As an added effect,
this will now disregard the the type of the indices passed to a GEP, so
"load GEP %A, i32 1" and "load GEP %A, i64 1" will result in a single argument,
not two.
This fixes PR2598, for which a testcase has been added as well.
llvm-svn: 54159
Remove the GetResultInst instruction. It is still accepted in LLVM assembly
and bitcode, where it is now auto-upgraded to ExtractValueInst. Also, remove
support for return instructions with multiple values. These are auto-upgraded
to use InsertValueInst instructions.
The IRBuilder still accepts multiple-value returns, and auto-upgrades them
to InsertValueInst instructions.
llvm-svn: 53941
return value as a whole in deadargelim is really not needed now that we simply
rebuild the old return value and actually prevents some canonicalization from
taking place.
This revert stops deadargelim from changing {i32} into i32 for now, but I'll
fix that next.
llvm-svn: 53609
return values that are still (partially) live. Instead of updating all uses of
a call instruction after removing some elements, it now just rebuilds the
original struct (With undef gaps where the unused values were) and leaves it to
instcombine to clean this up.
The added testcase still fails currently, but this is due to instcombine which
isn't good enough yet. I will fix that part next.
llvm-svn: 53608
only the liveness of partial return values (for functions returning a struct).
This is more explicit to prevent unwanted changes in the return value.
In particular, deadargelim now canonicalizes a function returning {i32} to
returning i32 and {} to void, if the struct returned is not used in its
entirety, but only the single element is used.
llvm-svn: 53606
Rewrite the DeadArgumentElimination pass, to use a more explicit tracking of
dependencies between return values and/or arguments. Also make the handling of
arguments and return values the same.
The pass now looks properly inside returned structs, but only at the first
level (ie, not inside nested structs).
This version fixed a few more bugs and was cleaned up a bit. It now passes all
of LLVM's testing, and should still pass SPEC2006. There is still a minor bug
with regard to returning nested structs. Since there is currently nothing that
emits such IR, I will fix that in a seperate commit (partly because it requires
a non-trivial fix).
llvm-svn: 53400
DeadArgumentElimination and assert that the function type does not change if
nothing was changed. This should catch subtle changes in function type that are
not intended.
llvm-svn: 52536
This is a fixed version that no longer uses multimap::equal_range, which
resulted in a pointer invalidation problem.
Also, DAE::InspectedFunctions was not really necessary, so it got removed.
Lastly, this version no longer applies the extra arg hack on functions who did
not have any arguments to start with.
llvm-svn: 52532
dependencies between return values and/or arguments. Also make the handling of
arguments and return values the same.
The pass now looks properly inside returned structs, but only at the first
level (ie, not inside nested structs).
Also add a testcase for testing various variations of (multiple) dead rerturn
values.
llvm-svn: 52459
speaking these are not constant values. However, when a function always returns
one of its arguments, then from the point of view of each caller the return
value is constant (or at least a known value) and can be replaced.
llvm-svn: 52397
individually.
Also learn IPConstProp how returning first class aggregates work, in addition
to old style multiple return instructions.
Modify the return-constants testscase to confirm this behaviour.
llvm-svn: 52396
the section or the visibility from one global
value to another: copyAttributesFrom. This is
particularly useful for duplicating functions:
previously this was done by explicitly copying
each attribute in turn at each place where a
new function was created out of an old one, with
the result that obscure attributes were regularly
forgotten (like the collector or the section).
Hopefully now everything is uniform and nothing
is forgotten.
llvm-svn: 51567
replaced at linktime with a body that throws, even
if the body in this file does not. Make PruneEH
be more conservative in this case.
g++.dg/eh/weak1.C
llvm-svn: 51207
a FunctionPass. This makes it simpler, fixes dozens of bugs, adds
a couple of minor features, and shrinks is considerably: from
2214 to 1437 lines.
llvm-svn: 50520
generalizes the previous code to handle the case when the string is not
an immediate to the strlen call (for example, crazy stuff like
strlen(c ? "foo" : "bart"+1) -> 3). This implements
gcc.c-torture/execute/builtins/strlen-2.c. I will generalize other
cases in simplifylibcalls to use the same routine later.
llvm-svn: 50408
2. Do not use # of basic blocks as part of the cost computation since it doesn't really figure into function size.
3. More aggressively inline function with vector code.
llvm-svn: 49061
Furthermore, double the limit when more than 10% of the callee instructions are vector instructions. Multimedia kernels tend to love inlining.
llvm-svn: 48725
1. There is now a "PAListPtr" class, which is a smart pointer around
the underlying uniqued parameter attribute list object, and manages
its refcount. It is now impossible to mess up the refcount.
2. PAListPtr is now the main interface to the underlying object, and
the underlying object is now completely opaque.
3. Implementation details like SmallVector and FoldingSet are now no
longer part of the interface.
4. You can create a PAListPtr with an arbitrary sequence of
ParamAttrsWithIndex's, no need to make a SmallVector of a specific
size (you can just use an array or scalar or vector if you wish).
5. All the client code that had to check for a null pointer before
dereferencing the pointer is simplified to just access the
PAListPtr directly.
6. The interfaces for adding attrs to a list and removing them is a
bit simpler.
Phase #2 will rename some stuff (e.g. PAListPtr) and do other less
invasive changes.
llvm-svn: 48289
This pass transforms
%struct._Point = type { i32, i32, i32, i32, i32, i32 }
define internal void @foo(%struct._Point* sret %agg.result)
into
%struct._Point = type { i32, i32, i32, i32, i32, i32 }
define internal %struct._Point @foo()
This pass updates foo() clients appropriately to use
getresult instruction to extract return values.
This pass is not yet ready for prime time.
llvm-svn: 47776
get away with it, which exposes opportunities to eliminate the memory
objects entirely. For example, we now compile byval.ll to:
define internal void @f1(i32 %b.0, i64 %b.1) {
entry:
%tmp2 = add i32 %b.0, 1 ; <i32> [#uses=0]
ret void
}
define i32 @main() nounwind {
entry:
call void @f1( i32 1, i64 2 )
ret i32 0
}
This seems like it would trigger a lot for code that passes around small
structs (e.g. SDOperand's or _Complex)...
llvm-svn: 45886
direct calls bails out unless caller and callee have essentially
equivalent parameter attributes. This is illogical - the callee's
attributes should be of no relevance here. Rework the logic, which
incidentally fixes a crash when removed arguments have attributes.
llvm-svn: 45658
return attributes on the floor. In the case of a call
to a varargs function where the varargs arguments are
being removed, any call attributes on those arguments
need to be dropped. I didn't do this because I plan to
make it illegal to have such attributes (see next patch).
With this change, compiling the gcc filter2 eh test at -O0
and then running opt -std-compile-opts on it results in
a correctly working program (compiling at -O1 or higher
results in the test failing due to a problem with how we
output eh info into the IR).
llvm-svn: 45285
calls 'nounwind'. It is important for correct C++
exception handling that nounwind markings do not get
lost, so this transformation is actually needed for
correctness.
llvm-svn: 45218
throw exceptions", just mark intrinsics with the nounwind
attribute. Likewise, mark intrinsics as readnone/readonly
and get rid of special aliasing logic (which didn't use
anything more than this anyway).
llvm-svn: 44544
the function type, instead they belong to functions
and function calls. This is an updated and slightly
corrected version of Reid Spencer's original patch.
The only known problem is that auto-upgrading of
bitcode files doesn't seem to work properly (see
test/Bitcode/AutoUpgradeIntrinsics.ll). Hopefully
a bitcode guru (who might that be? :) ) will fix it.
llvm-svn: 44359
from a file containing Function/BasicBlock pairings. This is not safe against
anonymous or abnormally-named Funcs or BBs.
Make bugpoint use this interface to pass the BBs list to the child bugpoint.
llvm-svn: 44101
The meaning of getTypeSize was not clear - clarifying it is important
now that we have x86 long double and arbitrary precision integers.
The issue with long double is that it requires 80 bits, and this is
not a multiple of its alignment. This gives a primitive type for
which getTypeSize differed from getABITypeSize. For arbitrary precision
integers it is even worse: there is the minimum number of bits needed to
hold the type (eg: 36 for an i36), the maximum number of bits that will
be overwriten when storing the type (40 bits for i36) and the ABI size
(i.e. the storage size rounded up to a multiple of the alignment; 64 bits
for i36).
This patch removes getTypeSize (not really - it is still there but
deprecated to allow for a gradual transition). Instead there is:
(1) getTypeSizeInBits - a number of bits that suffices to hold all
values of the type. For a primitive type, this is the minimum number
of bits. For an i36 this is 36 bits. For x86 long double it is 80.
This corresponds to gcc's TYPE_PRECISION.
(2) getTypeStoreSizeInBits - the maximum number of bits that is
written when storing the type (or read when reading it). For an
i36 this is 40 bits, for an x86 long double it is 80 bits. This
is the size alias analysis is interested in (getTypeStoreSize
returns the number of bytes). There doesn't seem to be anything
corresponding to this in gcc.
(3) getABITypeSizeInBits - this is getTypeStoreSizeInBits rounded
up to a multiple of the alignment. For an i36 this is 64, for an
x86 long double this is 96 or 128 depending on the OS. This is the
spacing between consecutive elements when you form an array out of
this type (getABITypeSize returns the number of bytes). This is
TYPE_SIZE in gcc.
Since successive elements in a SequentialType (arrays, pointers
and vectors) need to be aligned, the spacing between them will be
given by getABITypeSize. This means that the size of an array
is the length times the getABITypeSize. It also means that GEP
computations need to use getABITypeSize when computing offsets.
Furthermore, if an alloca allocates several elements at once then
these too need to be aligned, so the size of the alloca has to be
the number of elements multiplied by getABITypeSize. Logically
speaking this doesn't have to be the case when allocating just
one element, but it is simpler to also use getABITypeSize in this
case. So alloca's and mallocs should use getABITypeSize. Finally,
since gcc's only notion of size is that given by getABITypeSize, if
you want to output assembler etc the same as gcc then getABITypeSize
is the size you want.
Since a store will overwrite no more than getTypeStoreSize bytes,
and a read will read no more than that many bytes, this is the
notion of size appropriate for alias analysis calculations.
In this patch I have corrected all type size uses except some of
those in ScalarReplAggregates, lib/Codegen, lib/Target (the hard
cases). I will get around to auditing these too at some point,
but I could do with some help.
Finally, I made one change which I think wise but others might
consider pointless and suboptimal: in an unpacked struct the
amount of space allocated for a field is now given by the ABI
size rather than getTypeStoreSize. I did this because every
other place that reserves memory for a type (eg: alloca) now
uses getABITypeSize, and I didn't want to make an exception
for unpacked structs, i.e. I did it to make things more uniform.
This only effects structs containing long doubles and arbitrary
precision integers. If someone wants to pack these types more
tightly they can always use a packed struct.
llvm-svn: 43620
miscompilation of 188.ammp. Reject select and bitcast in
ValueIsOnlyUsedLocallyOrStoredToOneGlobal because RewriteHeapSROALoadUser can't handle it.
llvm-svn: 41950
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
as its main datastructure. There are many improvements yet to be made, but
this speeds up opt --std-compile-opts on 447.dealII by 7.3%.
llvm-svn: 34193
This happened because deadargelim now causes VMCore to auto-rename every
function that it hacks arguments out of. Because it hacks arguments out of
functions in a non-deterministic order, this caused the resultant numbering
to be nondet. The fix is to just be careful to not rename functions!
llvm-svn: 34005
the Transforms library. This reduces debug library size by 132 KB, debug
binary size by 376 KB, and reduces link time for llvm tools slightly.
llvm-svn: 33939
This patch replaces the SymbolTable class with ValueSymbolTable which does
not support types planes. This means that all symbol names in LLVM must now
be unique. The patch addresses the necessary changes to deal with this and
removes code no longer needed as a result. This completes the bulk of the
changes for this PR. Some cleanup patches will follow.
llvm-svn: 33918
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
1. New parameter attribute called 'inreg'. It has meaning "place this
parameter in registers, if possible". This is some generalization of
gcc's regparm(n) attribute. It's currently used only in X86-32 backend.
2. Completely rewritten CC handling/lowering code inside X86 backend.
Merged stdcall + c CCs and fastcall + fast CC.
3. Dropped CSRET CC. We cannot add struct return variant for each
target-specific CC (e.g. stdcall + csretcc and so on).
4. Instead of CSRET CC introduced 'sret' parameter attribute. Setting in
on first attribute has meaning 'This is hidden pointer to structure
return. Handle it gently'.
5. Fixed small bug in llvm-extract + add new feature to
FunctionExtraction pass, which relinks all internal-linkaged callees
from deleted function to external linkage. This will allow further
linking everything together.
NOTEs: 1. Documentation will be updated soon.
2. llvm-upgrade should be improved to translate csret => sret.
Before this, there will be some unexpected test fails.
llvm-svn: 33597
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
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
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
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
Take an incremental step towards type plane elimination. This change
separates types from values in the symbol tables by finally making use
of the TypeSymbolTable class. This yields more natural interfaces for
dealing with types and unclutters the SymbolTable class.
llvm-svn: 32956
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
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
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
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
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
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
DLL* linkages got full (I hope) codegeneration support in C & both x86
assembler backends.
External weak linkage added for future use, we don't provide any
codegeneration, etc. support for it.
llvm-svn: 30374
target CG node. This allows the inliner to properly update the callgraph
when using the pruning inliner. The pruning inliner may not copy over all
call sites from a callee to a caller, so the edges corresponding to those
call sites should not be copied over either.
This fixes PR827 and Transforms/Inline/2006-07-12-InlinePruneCGUpdate.ll
llvm-svn: 29120
are visible to analysis as intrinsics. That is, make sure someone doesn't pass
free around by address in some struct (as happens in say 176.gcc).
This doesn't get rid of any indirect calls, just ensure calls to free and malloc
are always direct.
llvm-svn: 27560
1. Do not statically construct a map when the program starts up, this
is expensive and cannot be optimized. Instead, create a list.
2. Do not insert entries for all function in the module into a hashmap
that lives the full life of the compiler.
llvm-svn: 25512
1. Use the varargs version of getOrInsertFunction to simplify code.
2. remove #include
3. Reduce the number of #ifdef's.
4. remove extraneous vertical whitespace.
llvm-svn: 25508
Don't do floor->floorf conversion if floorf is not available. This checks
the compiler's host, not its target, which is incorrect for cross-compilers
Not sure that's important as we don't build many cross-compilers.
llvm-svn: 25456
a) use better local variable names (OldMT -> OldFT) where "M" is used to
mean "Function" (perhaps it was previously "Method"?)
b) print out the module identifier in a warning message so that it is
possible to track down in which module the error occurred.
llvm-svn: 24698
Add support for specifying alignment and size of setjmp jmpbufs.
No targets currently do anything with this information, nor is it presrved
in the bytecode representation. That's coming up next.
llvm-svn: 24196
pointer marking the end of the list, the zero *must* be cast to the pointer
type. An un-cast zero is a 32-bit int, and at least on x86_64, gcc will
not extend the zero to 64 bits, thus allowing the upper 32 bits to be
random junk.
The new END_WITH_NULL macro may be used to annotate a such a function
so that GCC (version 4 or newer) will detect the use of un-casted zero
at compile time.
llvm-svn: 23888
Implement the start of global ctor optimization. It is currently smart
enough to remove the global ctor for cases like this:
struct foo {
foo() {}
} x;
... saving a bit of startup time for the program.
llvm-svn: 23433
SimplifyLibCalls probably has to be audited to make sure it does not make
this mistake elsewhere. Also, if this code knows that the type will be
unsigned, obviously one arm of this is dead.
Reid, can you take a look into this further?
llvm-svn: 22566
is a mismatch in their character type pointers (i.e. fprintf() prints an
array of ubytes while fwrite() takes an array of sbytes).
We can probably do better than this (such as casting the ubyte to an
sbyte).
llvm-svn: 22310
* Check for availability of ffsll call in configure script
* Support ffs, ffsl, and ffsll conversion to constant value if the argument
is constant.
llvm-svn: 22027
strlen(x) != 0 -> *x != 0
strlen(x) == 0 -> *x == 0
* Change nested statistics to use style of other LLVM statistics so that
only the name of the optimization (simplify-libcalls) is used as the
statistic name, and the description indicates which specific all is
optimized. Cuts down on some redundancy and saves a few bytes of space.
* Make note of stpcpy optimization that could be done.
llvm-svn: 21766
library function:
isdigit(chr) -> 0 or 1 if chr is constant
isdigit(chr) -> chr - '0' <= 9 otherwise
Although there are many calls to isdigit in llvm-test, most of them are
compiled away by macros leaving only this:
2 MultiSource/Applications/hexxagon
llvm-svn: 21688
actual spec (int -> uint)
* Add the ability to get/cache the strlen function prototype.
* Make sure generated values are appropriately named for debugging purposes
* Add the SPrintFOptimiation for 4 casts of sprintf optimization:
sprintf(str,cstr) -> llvm.memcpy(str,cstr) (if cstr has no %)
sprintf(str,"") -> store sbyte 0, str
sprintf(str,"%s",src) -> llvm.memcpy(str,src) (if src is constant)
sprintf(str,"%c",chr) -> store chr, str ; store sbyte 0, str+1
The sprintf optimization didn't fire as much as I had hoped:
2 MultiSource/Applications/SPASS
5 MultiSource/Benchmarks/McCat/18-imp
22 MultiSource/Benchmarks/Prolangs-C/TimberWolfMC
1 MultiSource/Benchmarks/Prolangs-C/assembler
6 MultiSource/Benchmarks/Prolangs-C/unix-smail
2 MultiSource/Benchmarks/mediabench/mpeg2/mpeg2dec
llvm-svn: 21679
Neither of these activated as many times as was hoped:
strchr:
9 MultiSource/Applications/siod
1 MultiSource/Applications/d
2 MultiSource/Prolangs-C/archie-client
1 External/SPEC/CINT2000/176.gcc/176.gcc
llvm.memset:
no hits
llvm-svn: 21669
strings passed to Statistic's constructor are not destructable. The stats
are printed during static destruction and the SimplifyLibCalls module was
getting destructed before the statistics.
llvm-svn: 21661
type be obtained from a CallInst we're optimizing.
* Make it possible for getConstantStringLength to return the ConstantArray
that it extracts in case the content is needed by an Optimization.
* Implement the strcmp optimization
* Implement the toascii optimization
This pass is now firing several to many times in the following MultiSource
tests:
Applications/Burg - 7 (strcat,strcpy)
Applications/siod - 13 (strcat,strcpy,strlen)
Applications/spiff - 120 (exit,fputs,strcat,strcpy,strlen)
Applications/treecc - 66 (exit,fputs,strcat,strcpy)
Applications/kimwitu++ - 34 (strcmp,strcpy,strlen)
Applications/SPASS - 588 (exit,fputs,strcat,strcpy,strlen)
llvm-svn: 21626
* Correct stale documentation in a few places
* Re-order the file to better associate things and reduce line count
* Make the pass thread safe by caching the Function* objects needed by the
optimizers in the pass object instead of globally.
* Provide the SimplifyLibCalls pass object to the optimizer classes so they
can access cached Function* objects and TargetData info
* Make sure the pass resets its cache if the Module passed to runOnModule
changes
* Rename CallOptimizer LibCallOptimization. All the classes are named
*Optimization while the objects are *Optimizer.
* Don't cache Function* in the optimizer objects because they could be used
by multiple PassManager's running in multiple threads
* Add an optimization for strcpy which is similar to strcat
* Add a "TODO" list at the end of the file for ideas on additional libcall
optimizations that could be added (get ideas from other compilers).
Sorry for the huge diff. Its mostly reorganization of code. That won't
happen again as I believe the design and infrastructure for this pass is
now done or close to it.
llvm-svn: 21589
call to them into an 'unreachable' instruction.
This triggers a bunch of times, particularly on gcc:
gzip: 36
gcc: 601
eon: 12
bzip: 38
llvm-svn: 21587
* MemCpyOptimization can only be optimized if the 3rd and 4th arguments are
constants and we weren't checking for that.
* The result of llvm.memcpy (and llvm.memmove) is void* not sbyte*, put in
a cast.
llvm-svn: 21570
* Have the SimplifyLibCalls pass acquire the TargetData and pass it down to
the optimization classes so they can use it to make better choices for
the signatures of functions, etc.
* Rearrange the code a little so the utility functions are closer to their
usage and keep the core of the pass near the top of the files.
* Adjust the StrLen pass to get/use the correct prototype depending on the
TargetData::getIntPtrType() result. The result of strlen is size_t which
could be either uint or ulong depending on the platform.
* Clean up some coding nits (cast vs. dyn_cast, remove redundant items from
a switch, etc.)
* Implement the MemMoveOptimization as a twin of MemCpyOptimization (they
only differ in name).
llvm-svn: 21569
named getConstantStringLength. This is the common part of StrCpy and
StrLen optimizations and probably several others, yet to be written. It
performs all the validity checks for looking at constant arrays that are
supposed to be null-terminated strings and then computes the actual
length of the string.
* Implement the MemCpyOptimization class. This just turns memcpy of 1, 2, 4
and 8 byte data blocks that are properly aligned on those boundaries into
a load and a store. Much more could be done here but alignment
restrictions and lack of knowledge of the target instruction set prevent
use from doing significantly more. That will have to be delegated to the
code generators as they lower llvm.memcpy calls.
llvm-svn: 21562
* Change signatures of OptimizeCall and ValidateCalledFunction so they are
non-const, allowing the optimization object to be modified. This is in
support of caching things used across multiple calls.
* Provide two functions for constructing and caching function types
* Modify the StrCatOptimization to cache Function objects for strlen and
llvm.memcpy so it doesn't regenerate them on each call site. Make sure
these are invalidated each time we start the pass.
* Handle both a GEP Instruction and a GEP ConstantExpr
* Add additional checks to make sure we really are dealing with an arary of
sbyte and that all the element initializers are ConstantInt or
ConstantExpr that reduce to ConstantInt.
* Make sure the GlobalVariable is constant!
* Don't use ConstantArray::getString as it can fail and it doesn't give us
the right thing. We must check for null bytes in the middle of the array.
* Use llvm.memcpy instead of memcpy so we can factor alignment into it.
* Don't use void* types in signatures, replace with sbyte* instead.
llvm-svn: 21555
* Don't use std::string for the function names, const char* will suffice
* Allow each CallOptimizer to validate the function signature before
doing anything
* Repeatedly loop over the functions until an iteration produces
no more optimizations. This allows one optimization to insert a
call that is optimized by another optimization.
* Implement the ConstantArray portion of the StrCatOptimization
* Provide a template for the MemCpyOptimization
* Make ExitInMainOptimization split the block, not delete everything
after the return instruction.
(This covers revision 1.3 and 1.4, as the 1.3 comments were botched)
llvm-svn: 21548
* Fix comments at top of file
* Change algorithm for running the call optimizations from n*n to something
closer to n.
* Use a hash_map to store and lookup the optimizations since there will
eventually (or potentially) be a large number of them. This gets lookup
based on the name of the function to O(1). Each CallOptimizer now has a
std::string member named func_name that tracks the name of the function
that it applies to. It is this string that is entered into the hash_map
for fast comparison against the function names encountered in the module.
* Cleanup some style issues pertaining to iterator invalidation
* Don't pass the Function pointer to the OptimizeCall function because if
the optimization needs it, it can get it from the CallInst passed in.
* Add the skeleton for a new CallOptimizer, StrCatOptimizer which will
eventually replace strcat's of constant strings with direct copies.
llvm-svn: 21526
calls. The pass visits all external functions in the module and determines
if such function calls can be optimized. The optimizations are specific to
the library calls involved. This initial version only optimizes calls to
exit(3) when they occur in main(): it changes them to ret instructions.
llvm-svn: 21522
in SPEC, the subsequent optimziations that we are after don't play with
with FP values, so disable this xform for them. Really we just don't want
stuff like:
double G; (always 0 or 412312.312)
= G;
turning into:
bool G_b;
= G_b ? 412312.312 : 0;
We'd rather just do the load.
-Chris
llvm-svn: 18819
down to actually BE a bool. This allows simple value range propagation
stuff work harder, deleting comparisons in bzip2 in some hot loops.
This implements GlobalOpt/integer-bool.ll, which is the essence of the
loop condition distilled into a testcase.
llvm-svn: 18817
in scary and unknown ways before we promote it. This fixes the miscompilation
of 188.ammp that has been plauging us since a globalopt patch went in.
Thanks a ton to Tanya for helping me diagnose the problem!
llvm-svn: 18418
value. This allows us to turn more globals into constants and eliminate them.
This patch implements GlobalOpt/load-store-global.llx.
Note that this patch speeds up 255.vortex from:
Output/255.vortex.out-cbe.time:program 7.640000
Output/255.vortex.out-llc.time:program 9.810000
to:
Output/255.vortex.out-cbe.time:program 7.250000
Output/255.vortex.out-llc.time:program 9.490000
Which isn't bad at all!
llvm-svn: 17746
constant value. This makes the return value dead and allows for
simplification in the caller.
This implements IPConstantProp/return-constant.ll
This triggers several dozen times throughout SPEC.
llvm-svn: 17730
argument pointers. This is only valid to do if the function already
unconditionally loaded an argument or if the pointer passed in is known
to be valid. Make sure to do the required checks.
This fixed ArgumentPromotion/control-flow.ll and the Burg program.
llvm-svn: 17718
This allows to elimination of a bunch of global pool descriptor args from
programs being pool allocated (and is also generally useful!)
llvm-svn: 17657
First, it allows SRA of globals that have embedded arrays, implementing
GlobalOpt/globalsra-partial.llx. This comes up infrequently, but does allow,
for example, deleting several stores to dead parts of globals in dhrystone.
Second, this implements GlobalOpt/malloc-promote-*.llx, which is the
following nifty transformation:
Basically if a global pointer is initialized with malloc, and we can tell
that the program won't notice, we transform this:
struct foo *FooPtr;
...
FooPtr = malloc(sizeof(struct foo));
...
FooPtr->A FooPtr->B
Into:
struct foo FooPtrBody;
...
FooPtrBody.A FooPtrBody.B
This comes up occasionally, for example, the 'disp' global in 183.equake (where
the xform speeds the CBE version of the program up from 56.16s to 52.40s (7%)
on apoc), and the 'desired_accept', 'fixLRBT', 'macroArray', & 'key_queue'
globals in 300.twolf (speeding it up from 22.29s to 21.55s (3.4%)).
The nice thing about this xform is that it exposes the resulting global to
global variable optimization and makes alias analysis easier in addition to
eliminating a few loads.
llvm-svn: 16916
still optimize away all of the indirect calls and loads, etc from it.
This turns code like this:
if (G != 0)
G();
into
if (G != 0)
ActualCallee();
This triggers a couple of times in gcc and libstdc++.
llvm-svn: 16901
stored to, but are stored at variable indexes. This occurs at least in
176.gcc, but probably others, and we should handle it for completeness.
llvm-svn: 16876
has a large number of users. Instead, just keep track of whether we're
making changes as we do so.
This patch has no functionlity changes.
llvm-svn: 16874
we know that all uses of the global will trap if the pointer contained is
null. In this case, we forward substitute the stored value to any uses.
This has the effect of devirtualizing trivial globals in trivial cases. For
example, 164.gzip contains this:
gzip.h:extern int (*read_buf) OF((char *buf, unsigned size));
bits.c: read_buf = file_read;
deflate.c: lookahead = read_buf((char*)window,
deflate.c: n = read_buf((char*)window+strstart+lookahead, more);
Since read_buf has to point to file_read at every use, we just replace
the calls through read_buf with a direct call to file_read.
This occurs in several benchmarks, including 176.gcc and 164.gzip. Direct
calls are good and stuff.
llvm-svn: 16871
* Do not lead dangling dead constants prevent optimization
* Iterate global optimization while we're making progress.
These changes allow us to be more aggressive, handling cases like
GlobalOpt/iterate.llx without a problem (turning it into 'ret int 0').
llvm-svn: 16857
optimizations to trigger much more often. This allows the elimination of
several dozen more global variables in Programs/External. Note that we only
do this for non-constant globals: constant globals will already be optimized
out if the accesses to them permit it.
This implements Transforms/GlobalOpt/globalsra.llx
llvm-svn: 16842
* Instead of handling dead functions specially, just nuke them.
* Be more aggressive about cleaning up after constification, in
particular, handle getelementptr instructions and constantexprs.
* Be a little bit more structured about how we process globals.
*** Delete globals that are only stored to, and never read. These are
clearly not useful, so they should go. This implements deadglobal.llx
This last one triggers quite a few times. In particular, 2208 in the
external tests, 1865 of which are in 252.eon. This shrinks eon from
1995094 to 1732341 bytes of bytecode.
llvm-svn: 16802
simplifications of the resultant program to avoid making later passes
do it all.
This allows us to constify globals that just have the same constant that
they are initialized stored into them.
Suprisingly this comes up ALL of the freaking time, dozens of times in
SPEC, 30 times in vortex alone.
For example, on 256.bzip2, it allows us to constify these two globals:
%smallMode = internal global ubyte 0 ; <ubyte*> [#uses=8]
%verbosity = internal global int 0 ; <int*> [#uses=49]
Which (with later optimizations) results in the bytecode file shrinking
from 82286 to 69686 bytes! Lets hear it for IPO :)
For the record, it's nuking lots of "if (verbosity > 2) { do lots of stuff }"
code.
llvm-svn: 16793
a function being deleted. Due to optimizations done while inlining, there
can be edges from the external call node to a function node that were not
apparent any longer.
This fixes the compiler crash while compiling 175.vpr
llvm-svn: 16399
Move include/Config and include/Support into include/llvm/Config,
include/llvm/ADT and include/llvm/Support. From here on out, all LLVM
public header files must be under include/llvm/.
llvm-svn: 16137
instructions in the body of the function (not the entry block). This fixes
test/Programs/SingleSource/Regression/C/2004-08-12-InlinerAndAllocas.c
and test/Programs/External/SPEC/CINT2000/176.gcc on zion.
This should obviously be pulled into 1.3.
llvm-svn: 15684
dangling constant users were removed from a function, causing it to be dead,
we never removed the call graph edge from the external node to the function.
In most cases, this didn't cause a problem (by luck). This should definitely
go into 1.3
llvm-svn: 15570
Gabor Greif