Commit Graph

6396 Commits

Author SHA1 Message Date
Jakob Stoklund Olesen 74bb06c0f0 Reintroduce the InlineHint function attribute.
This time it's for real! I am going to hook this up in the frontends as well.

The inliner has some experimental heuristics for dealing with the inline hint.
When given a -respect-inlinehint option, functions marked with the inline
keyword are given a threshold just above the default for -O3.

We need some experiments to determine if that is the right thing to do.

llvm-svn: 95466
2010-02-06 01:16:28 +00:00
Jakob Stoklund Olesen 5f9ead2714 Don't unroll loops containing function calls.
llvm-svn: 95454
2010-02-05 23:21:31 +00:00
Jakob Stoklund Olesen 916f48a054 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.

llvm-svn: 95439
2010-02-05 22:03:18 +00:00
Chris Lattner 64ffd11d49 fix logical-select to invoke filecheck right, and fix hte instcombine
xform it is checking to actually pass.  There is no need to match
m_SelectCst<0, -1> since instcombine canonicalizes that into not(sext).

Add matches for sext(not(x)) in addition to not(sext(x)).

llvm-svn: 95420
2010-02-05 19:53:02 +00:00
Dan Gohman 4739e41ce9 Implement releaseMemory in CodeGenPrepare and free the BackEdges
container data. This prevents it from holding onto dangling
pointers and potentially behaving unpredictably.

llvm-svn: 95409
2010-02-05 19:24:11 +00:00
Dan Gohman 8abb67df63 Use a SmallSetVector instead of a SetVector; this code showed up as a
malloc caller in a profile.

llvm-svn: 95407
2010-02-05 19:20:15 +00:00
Eric Christopher 04371b4f12 Remove this code for now. I have a better idea and will rewrite with
that in mind.

llvm-svn: 95402
2010-02-05 19:04:06 +00:00
Bob Wilson 27dfb1e1a4 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.

llvm-svn: 95333
2010-02-04 23:32:37 +00:00
Jakob Stoklund Olesen 113fb54bcb Increase inliner thresholds by 25.
This makes the inliner about as agressive as it was before my changes to the
inliner cost calculations. These levels give the same performance and slightly
smaller code than before.

llvm-svn: 95320
2010-02-04 18:48:20 +00:00
Eric Christopher 107a1fbf61 Temporarily revert this since it appears to have caused a build
failure.

llvm-svn: 95294
2010-02-04 06:41:27 +00:00
Eric Christopher 42fa84a880 Rework constant expr and array handling for objectsize instcombining.
Fix bugs where we would compute out of bounds as in bounds, and where
we couldn't know that the linker could override the size of an array.

Add a few new testcases, change existing testcase to use a private
global array instead of extern.

llvm-svn: 95283
2010-02-04 02:55:34 +00:00
Eric Christopher f12e18db21 If we're dealing with a zero-length array, don't lower to any
particular size, we just don't know what the length is yet.

llvm-svn: 95266
2010-02-03 23:56:07 +00:00
Bob Wilson 04365c5f72 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.

llvm-svn: 95224
2010-02-03 17:23:56 +00:00
Evan Cheng 27a41d5473 Revert 94937 and move the noreturn check to codegen.
llvm-svn: 95198
2010-02-03 03:55:59 +00:00
Bob Wilson 76e8c59509 Fix some comment typos.
llvm-svn: 95170
2010-02-03 00:33:21 +00:00
Eric Christopher d86233c118 Recommit this, looks like it wasn't the cause.
llvm-svn: 95165
2010-02-03 00:21:58 +00:00
Eric Christopher e67d01a9a8 Hopefully temporarily revert this.
llvm-svn: 95154
2010-02-02 23:01:31 +00:00
Eric Christopher f9553572b7 Reformat my last patch slightly.
llvm-svn: 95147
2010-02-02 22:29:26 +00:00
Eric Christopher 4264e7e46f Re-add strcmp and known size object size checking optimization.
Passed bootstrap and nightly test run here.

llvm-svn: 95145
2010-02-02 22:10:43 +00:00
Chris Lattner 8e2c471614 don't turn (A & (C0?-1:0)) | (B & ~(C0?-1:0)) -> C0 ? A : B
for vectors.  Codegen is generating awful code or segfaulting
in various cases (e.g. PR6204).

llvm-svn: 95058
2010-02-02 02:43:51 +00:00
Chris Lattner 302240d73e fix a crash in loop unswitch on a loop invariant vector condition.
llvm-svn: 95055
2010-02-02 02:26:54 +00:00
Dan Gohman 949458d014 LangRef.html says that inttoptr and ptrtoint always use zero-extension
when the cast is extending.

llvm-svn: 95046
2010-02-02 01:44:02 +00:00
Eric Christopher 14dfc3f6df Don't need to check the last argument since it'll always be bool. We also
don't use TargetData here.

llvm-svn: 95040
2010-02-02 00:51:45 +00:00
Eric Christopher 9afa973203 More indentation/tabification fixes.
llvm-svn: 95036
2010-02-02 00:13:06 +00:00
Eric Christopher 1408234753 Untabify previous commit.
llvm-svn: 95035
2010-02-02 00:06:55 +00:00
Eric Christopher 56e4182c49 Formatting.
llvm-svn: 95027
2010-02-01 23:25:03 +00:00
Bob Wilson d517b52012 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.

llvm-svn: 95007
2010-02-01 21:17:14 +00:00
Chris Lattner 9306ffa05a cleanups.
llvm-svn: 94995
2010-02-01 19:54:45 +00:00
Chris Lattner 846a52e228 fix rdar://7590304, a miscompilation of objc apps on arm. The caller
of objc message send was getting marked arm_apcscc, but the prototype
isn't.  This is fine at runtime because objcmsgsend is implemented in
assembly.  Only turn a mismatched caller and callee into 'unreachable'
if the callee is a definition.

llvm-svn: 94986
2010-02-01 18:11:34 +00:00
Chris Lattner 2cecedf081 fix rdar://7590304, an infinite loop in instcombine. In the invoke
case, instcombine can't zap the invoke for fear of changing the CFG.
However, we have to do something to prevent the next iteration of
instcombine from inserting another store -> undef before the invoke
thereby getting into infinite iteration between dead store elim and
store insertion.

Just zap the callee to null, which will prevent the next iteration
from doing anything.

llvm-svn: 94985
2010-02-01 18:04:58 +00:00
Bob Wilson f65ba356e1 Fix pr6198 by moving the isSized() check to an outer conditional.
The testcase from pr6198 does not crash for me -- I don't know what's up with
that -- so I'm not adding it to the tests.

llvm-svn: 94984
2010-02-01 17:41:44 +00:00
Eli Friedman a2cc2875fc Simplify/generalize the xor+add->sign-extend instcombine.
llvm-svn: 94943
2010-01-31 04:29:12 +00:00
Eli Friedman 37a8197b61 Add a small transform: transform -(X<<Y) to (-X<<Y) when the shift has a single
use and X is free to negate.

llvm-svn: 94941
2010-01-31 02:30:23 +00:00
Evan Cheng d86d3fe0c3 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.
llvm-svn: 94937
2010-01-31 00:59:31 +00:00
Bob Wilson 56600a15ad 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.

llvm-svn: 94875
2010-01-30 04:42:39 +00:00
Bob Wilson 4b71b6c179 Use more specific types to avoid casts. No functionality change.
llvm-svn: 94863
2010-01-30 00:41:10 +00:00
Jakob Stoklund Olesen e27dc727e2 Keep iterating over all uses when meeting a phi node in AllUsesOfValueWillTrapIfNull().
This bug was exposed by my inliner cost changes in r94615, and caused failures
of lencod on most architectures when building with LTO.

This patch fixes lencod and 464.h264ref on x86-64 (and likely others).

llvm-svn: 94858
2010-01-29 23:54:14 +00:00
Bob Wilson 1b8453067b Preserve load alignment in instcombine transformations. I've been unable to
create a testcase where this matters.  The select+load transformation only
occurs when isSafeToLoadUnconditionally is true, and in those situations,
instcombine also changes the underlying objects to be aligned.  This seems
like a good idea regardless, and I've verified that it doesn't pessimize
the subsequent realignment.

llvm-svn: 94850
2010-01-29 22:39:21 +00:00
Eric Christopher 5a0e174863 Revert my last couple of patches. They appear to have broken bison.
llvm-svn: 94841
2010-01-29 21:16:24 +00:00
Bob Wilson 34e10c2218 Use uint64_t instead of unsigned for offsets and sizes.
llvm-svn: 94835
2010-01-29 20:34:28 +00:00
Bob Wilson 7c42b9d51e 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.

llvm-svn: 94829
2010-01-29 19:19:08 +00:00
Duncan Sands c8a3e56870 Having RHSKnownZero and RHSKnownOne be alternative names for KnownZero and KnownOne
(via APInt &RHSKnownZero = KnownZero, etc) seems dangerous and confusing to me: it
is easy not to notice this, and then wonder why KnownZero/RHSKnownZero changed
underneath you when you modified RHSKnownZero/KnownZero etc.  So get rid of this.
No intended functionality change (tested with "make check" + llvm-gcc bootstrap).

llvm-svn: 94802
2010-01-29 06:18:46 +00:00
Eric Christopher 9b3c02b7da Make strcpy_chk lower to strcpy if we have a safe size.
llvm-svn: 94783
2010-01-29 01:37:11 +00:00
Eric Christopher 997f7ca8c5 Add constant support to object size handling and remove default
lowering. We'll either figure it out, or not and be lowered by
SelectionDAGBuild.

Add test.

llvm-svn: 94775
2010-01-29 01:09:57 +00:00
Bill Wendling 48816a0b3f Generic reformatting and comment fixing. No functionality change.
llvm-svn: 94771
2010-01-29 00:52:43 +00:00
Bill Wendling 8277838cf8 Add newline to debugging output, and fix some grammar-os in comment.
llvm-svn: 94765
2010-01-29 00:27:39 +00:00
Victor Hernandez 006b53f199 mem2reg erases the dbg.declare intrinsics that it converts to dbg.val intrinsics
llvm-svn: 94763
2010-01-29 00:01:35 +00:00
Duncan Sands 3a48b87c54 Fix PR6165. The bug was that LHSKnownZero was being and'd with DemandedMask
when it should have been and'd with LowBits.  Fix that and while there beef
up the logic in the case of a negative LHS.

llvm-svn: 94745
2010-01-28 17:22:42 +00:00
Bob Wilson 7577e948e4 Avoid creating redundant PHIs in SSAUpdater::GetValueInMiddleOfBlock.
This was already being done in SSAUpdater::GetValueAtEndOfBlock so I've
just changed SSAUpdater to check for existing PHIs in both places.

llvm-svn: 94690
2010-01-27 22:01:02 +00:00
Jeffrey Yasskin 091217be6f Kill ModuleProvider and ghost linkage by inverting the relationship between
Modules and ModuleProviders. Because the "ModuleProvider" simply materializes
GlobalValues now, and doesn't provide modules, it's renamed to
"GVMaterializer". Code that used to need a ModuleProvider to materialize
Functions can now materialize the Functions directly. Functions no longer use a
magic linkage to record that they're materializable; they simply ask the
GVMaterializer.

Because the C ABI must never change, we can't remove LLVMModuleProviderRef or
the functions that refer to it. Instead, because Module now exposes the same
functionality ModuleProvider used to, we store a Module* in any
LLVMModuleProviderRef and translate in the wrapper methods.  The bindings to
other languages still use the ModuleProvider concept.  It would probably be
worth some time to update them to follow the C++ more closely, but I don't
intend to do it.

Fixes http://llvm.org/PR5737 and http://llvm.org/PR5735.

llvm-svn: 94686
2010-01-27 20:34:15 +00:00