Commit Graph

3917 Commits

Author SHA1 Message Date
Eric Christopher
1926b648e1 Add a new pass to do llvm.objsize lowering using SCEV.
Initial skeleton and SCEVUnknown lowering implemented,
the rest should come relatively quickly.  Move testcase
to new directory.

Move pass to right before SimplifyLibCalls - which is
moved down a bit so we can take advantage of a few opts.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95628 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-09 00:35:38 +00:00
Jakob Stoklund Olesen
d450e5b886 Don't unroll loops containing function calls.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95454 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-05 23:21:31 +00:00
Jakob Stoklund Olesen
58e9ee85fd Teach SimplifyCFG about magic pointer constants.
Weird code sometimes uses pointer constants other than null. This patch
teaches SimplifyCFG to build switch instructions in those cases.

Code like this:

void f(const char *x) {
  if (!x)
    puts("null");
  else if ((uintptr_t)x == 1)
    puts("one");
  else if (x == (char*)2 || x == (char*)3)
    puts("two");
  else if ((intptr_t)x == 4)
    puts("four");
  else
    puts(x);
}

Now becomes a switch:

define void @f(i8* %x) nounwind ssp {
entry:
  %magicptr23 = ptrtoint i8* %x to i64            ; <i64> [#uses=1]
  switch i64 %magicptr23, label %if.else16 [
    i64 0, label %if.then
    i64 1, label %if.then2
    i64 2, label %if.then9
    i64 3, label %if.then9
    i64 4, label %if.then14
  ]

Note that LLVM's own DenseMap uses magic pointers.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95439 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-05 22:03:18 +00:00
Dan Gohman
aa0e523287 Implement releaseMemory in CodeGenPrepare and free the BackEdges
container data. This prevents it from holding onto dangling
pointers and potentially behaving unpredictably.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95409 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-05 19:24:11 +00:00
Bob Wilson
fc375d2200 Do not reassociate expressions with i1 type. SimplifyCFG converts some
short-circuited conditions to AND/OR expressions, and those expressions
are often converted back to a short-circuited form in code gen.  The
original source order may have been optimized to take advantage of the
expected values, and if we reassociate them, we change the order and
subvert that optimization.  Radar 7497329.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95333 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-04 23:32:37 +00:00
Bob Wilson
3992feb075 Adjust the heuristics used to decide when SROA is likely to be profitable.
The SRThreshold value makes perfect sense for checking if an entire aggregate
should be promoted to a scalar integer, but it is not so good for splitting
an aggregate into its separate elements.  A struct may contain a large embedded
array along with some scalar fields that would benefit from being split apart
by SROA.  Even if the total aggregate size is large, it may still be good to
perform SROA.  Thus, the most important piece of this patch is simply moving
the aggregate size comparison vs. SRThreshold so that it guards only the
aggregate promotion.

We have also been checking the number of elements to decide if an aggregate
should be split up.  The limit of "SRThreshold/4" seemed rather arbitrary,
and I don't think it's very useful to derive this limit from SRThreshold
anyway.  I've collected some data showing that the current default limit of
32 (since SRThreshold defaults to 128) is a reasonable cutoff for struct
types.  One thing suggested by the data is that distinguishing between structs
and arrays might be useful.  There are (obviously) a lot more large arrays
than large structs (as measured by the number of elements and not the total
size -- a large array inside a struct still counts as a single element given
the way we do SROA right now).  Out of 8377 arrays where we successfully
performed SROA while compiling a large set of benchmarks, only 16 of them had
more than 8 elements.  And, for those 16 arrays, it's not at all clear that
SROA was actually beneficial.  So, to offset the compile time cost of
investigating more large structs for SROA, the patch lowers the limit on array
elements to 8.

This fixes Apple Radar 7563690.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95224 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-03 17:23:56 +00:00
Evan Cheng
febc81680c Revert 94937 and move the noreturn check to codegen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95198 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-03 03:55:59 +00:00
Bob Wilson
e7b635f430 Fix some comment typos.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95170 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-03 00:33:21 +00:00
Eric Christopher
0c6a8f9eda Recommit this, looks like it wasn't the cause.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95165 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-03 00:21:58 +00:00
Eric Christopher
9f34dd305b Hopefully temporarily revert this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95154 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 23:01:31 +00:00
Eric Christopher
a6a089cd24 Re-add strcmp and known size object size checking optimization.
Passed bootstrap and nightly test run here.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95145 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 22:10:43 +00:00
Chris Lattner
3d606bbc92 fix a crash in loop unswitch on a loop invariant vector condition.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95055 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 02:26:54 +00:00
Eric Christopher
11225dd710 Don't need to check the last argument since it'll always be bool. We also
don't use TargetData here.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95040 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 00:51:45 +00:00
Eric Christopher
3a8bb73690 More indentation/tabification fixes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95036 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 00:13:06 +00:00
Eric Christopher
eae6ed1084 Untabify previous commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95035 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-02 00:06:55 +00:00
Eric Christopher
6ddf0430e1 Formatting.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95027 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-01 23:25:03 +00:00
Bob Wilson
6cad41778e Add an option to GVN to remove all partially redundant loads. This is currently
disabled by default.  This divides the existing load PRE code into 2 phases:
first it checks that it is safe to move the load to each of the predecessors
where it is unavailable, and then if it is safe, the code is changed to move
the load.  Radar 7571861.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95007 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-01 21:17:14 +00:00
Evan Cheng
56a5886b20 Do not mark no-return calls tail calls. It'll screw up special calls like longjmp and it doesn't make much sense for performance reason. If my logic is faulty, please let me know.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94937 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-31 00:59:31 +00:00
Bob Wilson
49db68fba0 Check alignment of loads when deciding whether it is safe to execute them
unconditionally.  Besides checking the offset, also check that the underlying
object is aligned as much as the load itself.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94875 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-30 04:42:39 +00:00
Eric Christopher
36664bfc7a Revert my last couple of patches. They appear to have broken bison.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94841 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 21:16:24 +00:00
Bob Wilson
3eb4f7e2dd Improve isSafeToLoadUnconditionally to recognize that GEPs with constant
indices are safe if the result is known to be within the bounds of the
underlying object.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94829 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 19:19:08 +00:00
Eric Christopher
407e47c21e Make strcpy_chk lower to strcpy if we have a safe size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94783 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 01:37:11 +00:00
Bill Wendling
466f37befb Generic reformatting and comment fixing. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94771 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 00:52:43 +00:00
Bill Wendling
9f9113a44b Add newline to debugging output, and fix some grammar-os in comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94765 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 00:27:39 +00:00
Benjamin Kramer
2d64ca09d4 Use the less expensive getName function instead of getNameStr.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94683 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-27 19:46:52 +00:00
Bob Wilson
0988639963 Remove check for an impossible condition: the condition of the while loop has
already checked that TmpBB->getSinglePredecessor() is non-null.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94451 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-25 21:28:05 +00:00
Bob Wilson
032742972f Change Value::getUnderlyingObject to have the MaxLookup value specified as a
parameter with a default value, instead of just hardcoding it in the
implementation.  The limit of MaxLookup = 6 was introduced in r69151 to fix
a performance problem with O(n^2) behavior in instcombine, but the scalarrepl
pass is relying on getUnderlyingObject to go all the way back to an AllocaInst.
Making the limit part of the method signature makes it clear that by default
the result is limited and should help avoid similar problems in the future.
This fixes pr6126.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94433 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-25 18:26:54 +00:00
Chris Lattner
43b5f9312d make -fno-rtti the default unless a directory builds with REQUIRES_RTTI.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94378 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-24 20:43:08 +00:00
Chris Lattner
d668839cb9 third bug from PR6119: the xor dupe extension allows
for arbitrary terminators in predecessors, don't assume
it is a conditional or uncond branch.  The testcase shows
an example where they can happen with switches.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94323 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 19:21:31 +00:00
Chris Lattner
2dd7657a5b add an early out to ProcessBranchOnXOR to speed it up,
handle the case when we can infer an input to the xor
from all inputs that agree, instead of going into an
infinite loop.  Another part of PR6199


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94321 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 19:16:25 +00:00
Chris Lattner
8231fd1e6c fix a crash in jump threading, PR6119
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94319 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 18:56:07 +00:00
Eric Christopher
7672d04f77 Reapply 94059 while fixing the calling convention setup
for strcpy.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94287 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-23 05:29:06 +00:00
Bob Wilson
8a23e0b07b Revert 94059. It is breaking the MultiSource/Benchmarks/Prolangs-C/bison
test on ARM.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94198 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-22 19:16:40 +00:00
Chris Lattner
e73a31f667 Stop building RTTI information for *most* llvm libraries. Notable
missing ones are libsupport, libsystem and libvmcore.  libvmcore is
currently blocked on bugpoint, which uses EH.  Once it stops using
EH, we can switch it off.

This #if 0's out 3 unit tests, because gtest requires RTTI information.
Suggestions welcome on how to fix this.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94164 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-22 06:49:46 +00:00
Dan Gohman
7979b72feb Revert LoopStrengthReduce.cpp to pre-r94061 for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94123 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-22 00:46:49 +00:00
Victor Hernandez
6c146eefbf DbgInfoIntrinsics no longer appear in an instruction's use list; so clean up looking for them in use iterations and remove OnlyUsedByDbgInfoIntrinsics()
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94111 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 23:05:53 +00:00
Dan Gohman
eca35b76ce When inserting expressions for post-increment users which contain
loop-variant components, adds must be inserted after the increment.
Keep track of the increment position for this case, and insert
these adds in the correct location.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94110 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 23:01:22 +00:00
Dan Gohman
940bd3e236 Include IVUsers information in LSR's debug output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94108 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 22:46:32 +00:00
Dan Gohman
8b0ade3eb8 Prune the search for candidate formulae if the number of register
operands exceeds the number of registers used in the initial
solution, as that wouldn't lead to a profitable solution anyway.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94107 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 22:42:49 +00:00
Dan Gohman
2f524587b6 Add a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94104 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 21:31:09 +00:00
Dan Gohman
a10756ee65 Re-implement the main strength-reduction portion of LoopStrengthReduction.
This new version is much more aggressive about doing "full" reduction in
cases where it reduces register pressure, and also more aggressive about
rewriting induction variables to count down (or up) to zero when doing so
reduces register pressure.

It currently uses fairly simplistic algorithms for finding reuse
opportunities, but it introduces a new framework allows it to combine
multiple strategies at once to form hybrid solutions, instead of doing
all full-reduction or all base+index.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94061 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 02:09:26 +00:00
Eric Christopher
ed1a4c7eab Add strcpy_chk -> strcpy support for "don't know" object size
answers.  This will update as object size checking gets better information.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94059 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 01:04:38 +00:00
Dan Gohman
d8d0b6a42c When doing address-mode sinking, expand the base register first, rather
than the scaled register. This makes it more likely that subsequent
AddrModeMatcher queries will match the new address the same way as the
old, instead of accidentally matching what had been the base register
as the new scaled register, and then failing to match the scaled register.
This fixes some problems with address-mode sinking multiple muls into a
block, which will be a lot more common with some upcoming
LoopStrengthReduction changes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93935 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-19 22:45:06 +00:00
Bob Wilson
a756b1d914 Fix a crash in scalarrepl for memcpy/memmove where the source and destination
are the same.  I had already fixed a similar problem where the source and
destination were different bitcasts derived from the same alloca, but the
previous fix still did not handle the case where both operands are exactly
the same value.  Radar 7552893.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93848 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-19 04:32:48 +00:00
Owen Anderson
a81e241fcc Convert some of the dynamic opcode lookups into static ones.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93693 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-17 19:33:27 +00:00
Chris Lattner
972a46c96a 1) Use the new SimplifyInstructionsInBlock routine instead of the copy
in JT.

2) When cloning blocks for PHI or xor conditions, use
instsimplify to simplify the code as we go.  This allows us to 
squish common cases early in JT which opens up opportunities for
subsequent iterations, and allows it to completely simplify the
testcase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93253 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-12 20:41:47 +00:00
Chris Lattner
797c440caf tidy up
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93222 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-12 02:07:50 +00:00
Chris Lattner
2249a0b1bd Teach jump threading to duplicate small blocks when the branch
condition is a xor with a phi node.  This eliminates nonsense
like this from 176.gcc in several places:

 LBB166_84:
        testl   %eax, %eax
-       setne   %al
-       xorb    %cl, %al
-       notb    %al
-       testb   $1, %al
-       je      LBB166_85
+       je      LBB166_69
+       jmp     LBB166_85

This is rdar://7391699



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93221 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-12 02:07:17 +00:00
Chris Lattner
77beb479f5 some cleanup, and make it obvious that ProcessJumpOnPHI only works
on branches by renaming it and checking for a branch at the call site.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93208 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-11 23:41:09 +00:00
Chris Lattner
c2d1b6949c only factor from expressions whose uses are empty and whose
base is the right expression type.  This fixes PR5981.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93045 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-09 06:01:36 +00:00