This makes reassociate realize that loads should be treated as unmovable, and
gives distinct ranks to distinct values defined in the same basic block, allowing
reassociate to do its thing.
llvm-svn: 21783
of trying to do local reassociation tweaks at each level, only process an expression
tree once (at its root). This does not improve the reassociation pass in any real way.
llvm-svn: 21768
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
the result, turn signed shift rights into unsigned shift rights if possible.
This leads to later simplification and happens *often* in 176.gcc. For example,
this testcase:
struct xxx { unsigned int code : 8; };
enum codes { A, B, C, D, E, F };
int foo(struct xxx *P) {
if ((enum codes)P->code == A)
bar();
}
used to be compiled to:
int %foo(%struct.xxx* %P) {
%tmp.1 = getelementptr %struct.xxx* %P, int 0, uint 0 ; <uint*> [#uses=1]
%tmp.2 = load uint* %tmp.1 ; <uint> [#uses=1]
%tmp.3 = cast uint %tmp.2 to int ; <int> [#uses=1]
%tmp.4 = shl int %tmp.3, ubyte 24 ; <int> [#uses=1]
%tmp.5 = shr int %tmp.4, ubyte 24 ; <int> [#uses=1]
%tmp.6 = cast int %tmp.5 to sbyte ; <sbyte> [#uses=1]
%tmp.8 = seteq sbyte %tmp.6, 0 ; <bool> [#uses=1]
br bool %tmp.8, label %then, label %UnifiedReturnBlock
Now it is compiled to:
%tmp.1 = getelementptr %struct.xxx* %P, int 0, uint 0 ; <uint*> [#uses=1]
%tmp.2 = load uint* %tmp.1 ; <uint> [#uses=1]
%tmp.2 = cast uint %tmp.2 to sbyte ; <sbyte> [#uses=1]
%tmp.8 = seteq sbyte %tmp.2, 0 ; <bool> [#uses=1]
br bool %tmp.8, label %then, label %UnifiedReturnBlock
which is the difference between this:
foo:
subl $4, %esp
movl 8(%esp), %eax
movl (%eax), %eax
shll $24, %eax
sarl $24, %eax
testb %al, %al
jne .LBBfoo_2
and this:
foo:
subl $4, %esp
movl 8(%esp), %eax
movl (%eax), %eax
testb %al, %al
jne .LBBfoo_2
This occurs 3243 times total in the External tests, 215x in povray,
6x in each f2c'd program, 1451x in 176.gcc, 7x in crafty, 20x in perl,
25x in gap, 3x in m88ksim, 25x in ijpeg.
Maybe this will cause a little jump on gcc tommorow :)
llvm-svn: 21715
This implements set.ll:test20.
This triggers 2x on povray, 9x on mesa, 11x on gcc, 2x on crafty, 1x on eon,
6x on perlbmk and 11x on m88ksim.
It allows us to compile these two functions into the same code:
struct s { unsigned int bit : 1; };
unsigned foo(struct s *p) {
if (p->bit)
return 1;
else
return 0;
}
unsigned bar(struct s *p) { return p->bit; }
llvm-svn: 21690
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
sinh, cosh, etc.
* Make the name comparisons for the fp libcalls a little more efficient by
switching on the first character of the name before doing comparisons.
llvm-svn: 21611
* 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
Completely rework the 'setcc (cast x to larger), y' code. This code has
the advantage of implementing setcc.ll:test19 (being more general than
the previous code) and being correct in all cases.
This allows us to unxfail 2004-11-27-SetCCForCastLargerAndConstant.ll,
and close PR454.
llvm-svn: 21491
Make IPSCCP strip off dead constant exprs that are using functions, making
them appear as though their address is taken. This allows us to propagate
some more pool descriptors, lowering the overhead of pool alloc.
llvm-svn: 21363
This pass forward branches through conditions when it can show that the
conditions is either always true or false for a predecessor. This currently
only handles the most simple cases of this, but is successful at threading
across 2489 branches and 65 switch instructions in 176.gcc, which isn't bad.
llvm-svn: 21306
* Loop invariant code does not dominate the loop header, but rather
the end of the loop preheader.
* The base for a reduced GEP isn't a constant unless all of its
operands (preceding the induction variable) are constant.
* Allow induction variable elimination for the simple case after all.
Also made changes recommended by Chris for properly deleting
instructions.
llvm-svn: 20383
This does a simple form of "jump threading", which eliminates CFG edges that
are provably dead. This triggers 90 times in the external tests, and
eliminating CFG edges is always always a good thing! :)
llvm-svn: 20300
and handle incomplete control dependences correctly. This fixes:
Regression/Transforms/ADCE/dead-phi-edge.ll
-> a missed optimization
Regression/Transforms/ADCE/dead-phi-edge.ll
-> a compiler crash distilled from QT4
llvm-svn: 20227
* Properly compile this:
struct a {};
int test() {
struct a b[2];
if (&b[0] != &b[1])
abort ();
return 0;
}
to 'return 0', not abort().
llvm-svn: 19875
The second folds operations into selects, e.g. (select C, (X+Y), (Y+Z))
-> (Y+(select C, X, Z)
This occurs a few times across spec, e.g.
select add/sub
mesa: 83 0
povray: 5 2
gcc 4 2
parser 0 22
perlbmk 13 30
twolf 0 3
llvm-svn: 19706
Disable the xform for < > cases. It turns out that the following is being
miscompiled:
bool %test(sbyte %S) {
%T = cast sbyte %S to uint
%V = setgt uint %T, 255
ret bool %V
}
llvm-svn: 19628
* We can now fold cast instructions into select instructions that
have at least one constant operand.
* We now optimize expressions more aggressively based on bits that are
known to be zero. These optimizations occur a lot in code that uses
bitfields even in simple ways.
* We now turn more cast-cast sequences into AND instructions. Before we
would only do this if it if all types were unsigned. Now only the
middle type needs to be unsigned (guaranteeing a zero extend).
* We transform sign extensions into zero extensions in several cases.
This corresponds to these test/Regression/Transforms/InstCombine testcases:
2004-11-22-Missed-and-fold.ll
and.ll: test28-29
cast.ll: test21-24
and-or-and.ll
cast-cast-to-and.ll
zeroext-and-reduce.ll
llvm-svn: 19220
SimplifyCFG is one of those passes that we use for final cleanup: it should
not rely on other passes to clean up its garbage. This fixes the "why are
trivially dead setcc's in the output of gccas" problem.
llvm-svn: 19212
do not insert a prototype for malloc of: void* malloc(uint): on 64-bit u
targets this is not correct. Instead of prototype it as void *malloc(...),
and pass the correct intptr_t through the "...".
Finally, fix Regression/CodeGen/SparcV9/2004-12-13-MallocCrash.ll, by not
forming constantexpr casts from pointer to uint.
llvm-svn: 18908
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
1. Actually increment the Statistic for the GV elim optzn
2. When resolving undef branches, only resolve branches in executable blocks,
avoiding marking a bunch of completely dead blocks live. This has a big
impact on the quality of the generated code.
With this patch, we positively rip up vortex, compiling Ut_MoveBytes to a
single memcpy call. In vortex we get this:
12 ipsccp - Number of globals found to be constant
986 ipsccp - Number of arguments constant propagated
1378 ipsccp - Number of basic blocks unreachable
8919 ipsccp - Number of instructions removed
llvm-svn: 18796
This implements SCCP/ipsccp-basic.ll, rips apart Olden/mst (as described in
PR415), and does other nice things.
There is still more to come with this, but it's a start.
llvm-svn: 18752
successor block. This turns cases like this:
x = a op b
if (c) {
use x
}
into:
if (c) {
x = a op b
use x
}
This triggers 3965 times in spec, and is tested by
Regression/Transforms/InstCombine/sink_instruction.ll
This appears to expose a bug in the X86 backend for 177.mesa, which I'm
looking in to.
llvm-svn: 18677
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
if (x) {
code
...
} else {
code
...
}
Turn it into:
code
if (x) {
...
} else {
...
}
This reduces code size and in some common cases allows us to completely
eliminate the conditional. This turns several if/then/else blocks in loops
into straightline code in 179.art, turning the loops into single basic blocks
(good for modsched even!).
Maybe now brg will leave me alone ;-)
llvm-svn: 18366
1. Speedup getValueState by having it not consider Arguments. It's better
to just add them before we start SCCP'ing.
2. SCCP can delete the contents of dead blocks. No really, it's ok! This
reduces the size of the IR for subsequent passes, even though
simplifycfg would do the same job. In practice, simplifycfg does not
run until much later than sccp in gccas
llvm-svn: 17820
class. The only changes are minor:
* Do not try to SCCP instructions that return void in the rewrite loop.
This is silly and fool hardy, wasting a map lookup and adding an entry
to the map which is never used.
* If we decide something has an undefined value, rewrite it to undef,
potentially leading to further simplications.
llvm-svn: 17816
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
If this happens, detect it early instead of relying on instcombine to notice
it later. This can be a big speedup, because PHI nodes can have many
incoming values.
llvm-svn: 17741
%X = alloca ...
%Y = alloca ...
X == Y
into false. This allows us to simplify some stuff in eon (and probably
many other C++ programs) where operator= was checking for self assignment.
Folding this allows us to SROA several additional structs.
llvm-svn: 17735
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
of the array is just two. This occurs 8 times in gcc, 6 times in crafty, and
12 times in 099.go.
This implements ScalarRepl/sroa_two.ll
llvm-svn: 17727
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
for (X * C1) + (X * C2) (where * can be mul or shl), allowing us to fold:
Y+Y+Y+Y+Y+Y+Y+Y
into
%tmp.8 = shl long %Y, ubyte 3 ; <long> [#uses=1]
instead of
%tmp.4 = shl long %Y, ubyte 2 ; <long> [#uses=1]
%tmp.12 = shl long %Y, ubyte 2 ; <long> [#uses=1]
%tmp.8 = add long %tmp.4, %tmp.12 ; <long> [#uses=1]
This implements add.ll:test25
Also add support for (X*C1)-(X*C2) -> X*(C1-C2), implementing sub.ll:test18
llvm-svn: 17704
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
loops. This optimization is not turned on by default yet, but may be run
with the opt tool's -loop-reduce flag. There are many FIXMEs listed in the
code that will make it far more applicable to a wide range of code, but you
have to start somewhere :)
This limited version currently triggers on the following tests in the
MultiSource directory:
pcompress2: 7 times
cfrac: 5 times
anagram: 2 times
ks: 6 times
yacr2: 2 times
llvm-svn: 17134
change hacks off 10K of bytecode from perlbmk (.5%) even though the front-end
is not generating them yet and we are not optimizing the resultant code.
This isn't too bad.
llvm-svn: 17111
exercise that I'm not interested in tackling right now. Just punt and treat them
like unwind's.
This 'fixes' test/Regression/Transforms/ADCE/unreachable-function.ll
llvm-svn: 17106
unneccesary. This allows us to delete several hundred phi nodes of the
form PHI(x,x,x,undef) from 253.perlbmk and probably other programs as well.
This implements Mem2Reg/UndefValuesMerge.ll
llvm-svn: 17098
pointer recurrences into expressions from this:
%P_addr.0.i.0 = phi sbyte* [ getelementptr ([8 x sbyte]* %.str_1, int 0, int 0), %entry ], [ %inc.0.i, %no_exit.i ]
%inc.0.i = getelementptr sbyte* %P_addr.0.i.0, int 1 ; <sbyte*> [#uses=2]
into this:
%inc.0.i = getelementptr sbyte* getelementptr ([8 x sbyte]* %.str_1, int 0, int 0), int %inc.0.i.rec
Actually create something nice, like this:
%inc.0.i = getelementptr [8 x sbyte]* %.str_1, int 0, int %inc.0.i.rec
llvm-svn: 16924
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
an instruction if it can be hoisted to a common dominator of the block.
This implements: test/Regression/Transforms/TailDup/MergeTest.ll
llvm-svn: 16758
* SubOne/AddOne functions always return ConstantInt, declare them as such
* Pull code for handling setcc X, cst, where cst is at the end of the range,
or cc is LE or GE up earlier in visitSetCondInst. This reduces #iterations
in some cases.
* Fold: (div X, C1) op C2 -> range check, implementing div.ll:test6 - test9.
llvm-svn: 16588
This takes something like this:
%A = phi int [ 3, %cond_false.0 ], [ 2, %endif.0.i ], [ 2, %endif.1.i ]
%B = div int %tmp.243, 4
and turns it into:
%A = phi int [ 3/4, %cond_false.0 ], [ 2/4, %endif.0.i ], [ 2/4, %endif.1.i ]
which is later simplified (in this case) into %A = 0.
This triggers thousands of times in spec, for example, 269 times in 176.gcc.
This is tested by InstCombine/add.ll:test23 and set.ll:test18.
llvm-svn: 16582
Instcombine (setcc (truncate X), C1).
This occurs THOUSANDS of times in many benchmarks. Particularlly common
seem to be things like (seteq (cast bool X to int), int 0)
This turns it into (seteq bool %X, false), which then becomes (not %X).
llvm-svn: 16567
This is important for several reasons:
1. Benchmarks have lots of code that looks like this (perlbmk in particular):
%tmp.2.i = setne int %tmp.0.i, 128 ; <bool> [#uses=1]
%tmp.6343 = seteq int %tmp.0.i, 1 ; <bool> [#uses=1]
%tmp.63 = and bool %tmp.2.i, %tmp.6343 ; <bool> [#uses=1]
we now fold away the setne, a clear improvement.
2. In the more important cases, such as (X >= 10) & (X < 20), we now produce
smaller code: (X-10) < 10.
3. Perhaps the nicest effect of this patch is that it really helps out the
code generators. In particular, for a 'range test' like the above,
instead of generating this on X86 (the difference on PPC is even more
pronounced):
cmp %EAX, 50
setge %CL
cmp %EAX, 100
setl %AL
and %CL, %AL
cmp %CL, 0
we now generate this:
add %EAX, -50
cmp %EAX, 50
Furthermore, this causes setcc's to be folded into branches more often.
These combinations trigger dozens of times in the spec benchmarks, particularly
in 176.gcc, 186.crafty, 253.perlbmk, 254.gap, & 099.go.
llvm-svn: 16559
Implement (setcc (shl X, C1), C2) folding.
The second one occurs several dozen times in spec. The first was added
just in case. :)
These are tested by shift.ll:test2[12], and div.ll:test5
llvm-svn: 16549
This latent bug was exposed by recent changes, and is tested as:
llvm/test/Regression/Transforms/InstCombine/2004-09-28-BadShiftAndSetCC.llx
llvm-svn: 16546
triggers often, for example:
6x in povray, 1x in gzip, 279x in gcc, 1x in crafty, 8x in eon, 11x in perlbmk,
362x in gap, 4x in vortex, 14 in m88ksim, 211x in 126.gcc, 1x in compress,
11x in ijpeg, and 4x in 147.vortex.
llvm-svn: 16521
whose addresses where used by trivial phi nodes and select instructions. This
is now performed by the instcombine pass, which is more powerful, is much
simpler, and is faster. This allows the deletion of a bunch of code, two
FIXME's and two gotos.
llvm-svn: 16406
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
block (common in a switch), make sure to remove extra edges in successor
blocks. This fixes CodeExtractor/2004-08-12-BlockExtractPHI.ll and should
be pulled into LLVM 1.3 (though the regression test need not be, as that
would require pulling in the LoopExtract.cpp changes).
llvm-svn: 15717
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
1. Fix a REALLY nasty cyclic replacement issue that Anshu discovered, causing
nondeterminstic crashes and memory corruption.
2. For performance, don't go inserting constantexpr casts of GV pointers.
This should definitely go into 1.3
llvm-svn: 15568
assumed that a constant on the RHS of a multiplication was either an
IntConstant or an FPConstant. It checked for an IntConstant and then,
if it did not find one, did a hard cast to an FPConstant. That code
would crash if the RHS were a ConstantExpr that was neither an
IntConstant nor an FPConstant. This version replaces the hard cast
with a dyn_cast. It performs the same way for IntConstants and
FPConstants but does nothing, instead of crashing, for constant
expressions.
The regression test for this change is 2004-07-27-ConstantExprMul.ll.
llvm-svn: 15291
a bug in DSE).
* Delete dead operand uses iteratively instead of recursively, using a
SetVector.
* Defer deletion of dead operand uses until the end of processing, which means
we don't have to bother with updating the AliasSetTracker. This speeds up
DSE substantially.
llvm-svn: 15204
* Test for whether bits are shifted out during the optzn.
If so, the fold is illegal, though it can be handled explicitly for setne/seteq
This fixes the miscompilation of 254.gap last night, which was a latent bug
exposed by other optimizer improvements.
llvm-svn: 15085
actually care about. Someday when the cast instruction is gone, we can do
better here, but this will do for now. This implements
instcombine/cast.ll:test17/18 as well.
llvm-svn: 15018
This eliminates an N*N*logN algorithm from the loop simplify pass, replacing
it with a much simpler and faster alternative. In a debug build, this reduces
gccas time on eon from 85s to 42s.
llvm-svn: 14851
"load (cast foo)". This allows us to compile C++ code like this:
class Bclass {
public: virtual int operator()() { return 666; }
};
class Dclass: public Bclass {
public: virtual int operator()() { return 667; }
} ;
int main(int argc, char** argv) {
Dclass x;
return x();
}
Into this:
int %main(int %argc, sbyte** %argv) {
entry:
call void %__main( )
ret int 667
}
Instead of this:
int %main(int %argc, sbyte** %argv) {
entry:
%x = alloca "struct.std::bad_typeid" ; <"struct.std::bad_typeid"*> [#uses=3]
call void %__main( )
%tmp.1.i.i = getelementptr "struct.std::bad_typeid"* %x, uint 0, uint 0, uint 0 ; <int (...)***> [#uses=1]
store int (...)** getelementptr ([3 x int (...)*]* %vtable for Bclass, int 0, long 2), int (...)*** %tmp.1.i.i
%tmp.3.i = getelementptr "struct.std::bad_typeid"* %x, int 0, uint 0, uint 0 ; <int (...)***> [#uses=1]
store int (...)** getelementptr ([3 x int (...)*]* %vtable for Dclass, int 0, long 2), int (...)*** %tmp.3.i
%tmp.5 = load int ("struct.std::bad_typeid"*)** cast (int (...)** getelementptr ([3 x int (...)*]* %vtable for Dclass, int 0, long 2) to int
("struct.std::bad_typeid"*)**) ; <int ("struct.std::bad_typeid"*)*> [#uses=1]
%tmp.6 = call int %tmp.5( "struct.std::bad_typeid"* %x ) ; <int> [#uses=1]
ret int %tmp.6
ret int 0
}
In order words, we now resolve the virtual function call.
llvm-svn: 14783
Don't touch GEPs for which DecomposeArrayRef is not going to do anything
special (e.g., < 2 indices, or 2 indices and the last one is a constant.)
llvm-svn: 14647
since May 1st. In this code, the pred iterator was being invalidated sometimes
causing the wrong entries to be added to PHI nodes.
The fix for this is to defererence and safe the *PI value before we hack on
branch instructions, which changes use/def chains, which SOMETIMES invalidates
the iterator.
llvm-svn: 14278
non-deterministic things like the ordering of blocks in the dominance
frontier of a BB. Unfortunately, I don't know of a better way to solve
this problem than to explicitly sort the BB's in function-order before
processing them. This is guaranteed to slow the pass down a bit, but
is absolutely necessary to get usable diffs between two different tools
executing the mem2reg or scalarrepl pass.
Before this, bazillions of spurious diff failures occurred all over the
place due to the different order of processing PHIs:
- %tmp.111 = getelementptr %struct.Connector_struct* %upcon.0.0, uint 0, uint 0
+ %tmp.111 = getelementptr %struct.Connector_struct* %upcon.0.1, uint 0, uint 0
Now, the diffs match.
llvm-svn: 14244
nondeterministic results that depend on where these objects land in memory.
Instead, sort by the value of the constant, which is stable.
Before this patch, the -simplifycfg pass run from two different compilers
could cause different code to be generated, though it was semantically the
same:
@@ -12258,8 +12258,8 @@
%s_addr.1 = phi sbyte* [ %s, %entry ], [ %inc.0, %no_exit ] ; <sbyte*> [#uses=5]
%tmp.1 = load sbyte* %s_addr.1 ; <sbyte> [#uses=1]
switch sbyte %tmp.1, label %no_exit [
- sbyte 0, label %loopexit
sbyte 46, label %loopexit
+ sbyte 0, label %loopexit
]
We need to stomp all of this stuff out.
llvm-svn: 14243
is write an autoconf macro that checks whether __isnan or isnan actually works
**using the C++ compiler after #include <cmath>**, instead of doing it the easy
way with AC_CHECK_FUNCS().
llvm-svn: 14171
186.crafty, fhourstones and 132.ijpeg.
Bugpoint makes really nasty miscompilations embarassingly easy to find. It
narrowed it down to the instcombiner and this testcase (from fhourstones):
bool %l7153_l4706_htstat_loopentry_2E_4_no_exit_2E_4(int* %i, [32 x int]* %works, int* %tmp.98.out) {
newFuncRoot:
%tmp.96 = load int* %i ; <int> [#uses=1]
%tmp.97 = getelementptr [32 x int]* %works, long 0, int %tmp.96 ; <int*> [#uses=1]
%tmp.98 = load int* %tmp.97 ; <int> [#uses=2]
%tmp.99 = load int* %i ; <int> [#uses=1]
%tmp.100 = and int %tmp.99, 7 ; <int> [#uses=1]
%tmp.101 = seteq int %tmp.100, 7 ; <bool> [#uses=2]
%tmp.102 = cast bool %tmp.101 to int ; <int> [#uses=0]
br bool %tmp.101, label %codeRepl4.exitStub, label %codeRepl3.exitStub
codeRepl4.exitStub: ; preds = %newFuncRoot
store int %tmp.98, int* %tmp.98.out
ret bool true
codeRepl3.exitStub: ; preds = %newFuncRoot
store int %tmp.98, int* %tmp.98.out
ret bool false
}
... which only has one combination performed on it:
$ llvm-as < t.ll | opt -instcombine -debug | llvm-dis
IC: Old = %tmp.101 = seteq int %tmp.100, 7 ; <bool> [#uses=1]
New = setne int %tmp.100, 0 ; <bool>:<badref> [#uses=0]
IC: MOD = br bool %tmp.101, label %codeRepl3.exitStub, label %codeRepl4.exitStub
IC: MOD = %tmp.97 = getelementptr [32 x int]* %works, uint 0, int %tmp.96 ; <int*> [#uses=1]
It doesn't get much better than this. :)
llvm-svn: 14109
collapse this:
bool %le(int %A, int %B) {
%c1 = setgt int %A, %B
%tmp = select bool %c1, int 1, int 0
%c2 = setlt int %A, %B
%result = select bool %c2, int -1, int %tmp
%c3 = setle int %result, 0
ret bool %c3
}
into:
bool %le(int %A, int %B) {
%c3 = setle int %A, %B ; <bool> [#uses=1]
ret bool %c3
}
which is handy, because the Java FE makes these sequences all over the place.
This is tested as: test/Regression/Transforms/InstCombine/JavaCompare.ll
llvm-svn: 14086
This code hadn't been updated after the "structs with more than 256 elements"
related changes to the GEP instruction. Also it was not handling the
ConstantAggregateZero class.
Now it does!
llvm-svn: 13834
Add support for acos/asin/atan. 188.ammp contains three calls to acos with
constant arguments. Constant folding it allows elimination of those 3 calls
and three FP divisions of the results.
llvm-svn: 13821
into (X & (C2 << C1)) != (C3 << C1), where the shift may be either left or
right and the compare may be any one.
This triggers 1546 times in 176.gcc alone, as it is a common pattern that
occurs for bitfield accesses.
llvm-svn: 13740
CloneTrace, and because it is primarily an operation on ValueMaps. It
is now a global (non-static) function which can be pulled in using
ValueMapper.h.
llvm-svn: 13600
Add better comments, including a better head-of-file comment.
Prune #includes.
Fix a FIXME that Chris put here by using doInitialization().
Use DEBUG() to print out debug msgs.
Give names to basic blocks inserted by this pass.
Expand tabs.
Use InsertProfilingInitCall() from ProfilingUtils to insert the initialize call.
llvm-svn: 13581
in the size calculation.
This is not something you want to see:
Loop Unroll: F[main] Loop %no_exit Loop Size = 2 Trip Count = 2147483648 - UNROLLING!
The problem was that 2*2147483648 == 0.
Now we get:
Loop Unroll: F[main] Loop %no_exit Loop Size = 2 Trip Count = 2147483648 - TOO LARGE: 4294967296>100
Thanks to some anonymous person playing with the demo page that repeatedly
caused zion to go into swapping land. That's one way to ensure you'll get
a quick bugfix. :)
Testcase here: Transforms/LoopUnroll/2004-05-13-DontUnrollTooMuch.ll
llvm-svn: 13564
PHI node entries from multiple outside-the-region blocks. This also fixes
extraction of the entry block in a function. Yaay.
This has successfully block extracted all (but one) block from the score_move
function in obsequi (out of 33). Hrm, I wonder which block the bug is in. :)
llvm-svn: 13489
* Add a stub for the severSplitPHINodes which will allow us to bbextract
bb's with PHI nodes in them soon.
* Remove unused arguments from findInputsOutputs
* Dramatically simplify the code in findInputsOutputs. In particular,
nothing really cares whether or not a PHI node is using something.
* Move moveCodeToFunction to after emitCallAndSwitchStatement as that's the
order they get called.
* Fix a bug where we would code extract a region that included a call to
vastart. Like 'alloca', calls to vastart must stay in the function that
they are defined in.
* Add some comments.
llvm-svn: 13482
from the extracted region. If the return has 0 or 1 exit blocks, the new
function returns void. If it has 2 exits, it returns bool, otherwise it
returns a ushort as before.
This allows us to use a conditional branch instruction when there are two
exit blocks, as often happens during block extraction.
llvm-svn: 13481
1. Get rid of the silly abort block. When doing bb extraction, we get one
abort block for every block extracted, which is kinda annoying.
2. If the switch ends up having a single destination, turn it into an
unconditional branch.
I would like to add support for conditional branches, but to do this we will
want to have the function return a bool instead of a ushort.
llvm-svn: 13478
%tmp.0 = getelementptr [50 x sbyte]* %ar, uint 0, int 5 ; <sbyte*> [#uses=2]
%tmp.7 = getelementptr sbyte* %tmp.0, int 8 ; <sbyte*> [#uses=1]
together. This patch actually allows us to simplify and generalize the code.
llvm-svn: 13415
is only used by a cast, and the casted type is the same size as the original
allocation, it would eliminate the cast by folding it into the allocation.
Unfortunately, it was placing the new allocation instruction right before
the cast, which could pull (for example) alloca instructions into the body
of a function. This turns statically allocatable allocas into expensive
dynamically allocated allocas, which is bad bad bad.
This fixes the problem by placing the new allocation instruction at the same
place the old one was, duh. :)
llvm-svn: 13289
loop. This eliminates the extra add from the previous case, but it's
not clear that this will be a performance win overall. Tommorows test
results will tell. :)
llvm-svn: 13103
Eventually it would be nice if CallGraph maintained an ilist of CallGraphNode's instead
of a vector of pointers to them, but today is not that day.
llvm-svn: 13100
block. The primary motivation for doing this is that we can now unroll nested loops.
This makes a pretty big difference in some cases. For example, in 183.equake,
we are now beating the native compiler with the CBE, and we are a lot closer
with LLC.
I'm now going to play around a bit with the unroll factor and see what effect
it really has.
llvm-svn: 13034
limited. Even in it's extremely simple state (it can only *fully* unroll single
basic block loops that execute a constant number of times), it already helps improve
performance a LOT on some benchmarks, particularly with the native code generators.
llvm-svn: 13028
Basically we were using SimplifyCFG as a huge sledgehammer for a simple
optimization. Because simplifycfg does so many things, we can't use it
for this purpose.
llvm-svn: 12977
Instead of producing code like this:
Loop:
X = phi 0, X2
...
X2 = X + 1
if (X != N-1) goto Loop
We now generate code that looks like this:
Loop:
X = phi 0, X2
...
X2 = X + 1
if (X2 != N) goto Loop
This has two big advantages:
1. The trip count of the loop is now explicit in the code, allowing
the direct implementation of Loop::getTripCount()
2. This reduces register pressure in the loop, and allows X and X2 to be
put into the same register.
As a consequence of the second point, the code we generate for loops went
from:
.LBB2: # no_exit.1
...
mov %EDI, %ESI
inc %EDI
cmp %ESI, 2
mov %ESI, %EDI
jne .LBB2 # PC rel: no_exit.1
To:
.LBB2: # no_exit.1
...
inc %ESI
cmp %ESI, 3
jne .LBB2 # PC rel: no_exit.1
... which has two fewer moves, and uses one less register.
llvm-svn: 12961
Chris Lattner