The reason that this occurs is that tail calling objc_autorelease eventually
tail calls -[NSObject autorelease] which supports fast autorelease. This can
cause us to violate the semantic gaurantees of __autoreleasing variables that
assignment to an __autoreleasing variables always yields an object that is
placed into the innermost autorelease pool.
The fix included in this patch works by:
1. In the peephole optimization function OptimizeIndividualFunctions, always
remove tail call from objc_autorelease.
2. Whenever we convert to/from an objc_autorelease, set/unset the tail call
keyword as appropriate.
*NOTE* I also handled the case where objc_autorelease is converted in
OptimizeReturns to an autoreleaseRV which still violates the ARC semantics. I
will be removing that in a later patch and I wanted to make sure that the tree
is in a consistent state vis-a-vis ARC always.
Additionally some test cases are provided and all tests that have tail call marked
objc_autorelease keywords have been modified so that tail call has been removed.
*NOTE* One test fails due to a separate bug that I am going to commit soon. Thus
I marked the check line TMP: instead of CHECK: so make check does not fail.
llvm-svn: 172287
Specifically:
1. Added a missing new line when we emit a debug message saying that we are marking a global variable as constant.
2. Added debug messages that describe what is occuring when GlobalOpt is evaluating a block/function.
3. Added a debug message that says what specific constructor is being evaluated.
llvm-svn: 172247
We don't have a detailed analysis on which values are vectorized and which stay scalars in the vectorized loop so we use
another method. We look at reduction variables, loads and stores, which are the only ways to get information in and out
of loop iterations. If the data types are extended and truncated then the cost model will catch the cost of the vector
zext/sext/trunc operations.
llvm-svn: 172178
This fixes va_start/va_copy of a va_list field which happens to not
be laid out at a 16-byte boundary.
Differential Revision: http://llvm-reviews.chandlerc.com/D276
llvm-svn: 172128
1. Added debug messages when in OptimizeIndividualCalls we move calls into predecessors and then erase the original call.
2. Added debug messages when in the process of moving calls in ObjCARCOpt::MoveCalls we create new RR and delete old RR.
3. Added a debug message when we visit a specific retain instruction in ObjCARCOpt::PerformCodePlacement.
llvm-svn: 171988
small loops. On small loops post-loop that handles scalars (and runs slower) can take more time to execute than the
rest of the loop. This patch disables widening of loops with a small static trip count.
llvm-svn: 171798
o. X/C1 * C2 => X * (C2/C1) (if C2/C1 is neither special FP nor denormal)
o. X/C1 * C2 -> X/(C1/C2) (if C2/C1 is either specical FP or denormal, but C1/C2 is a normal Fp)
Let MDC denote multiplication or dividion with one & only one operand being a constant
o. (MDC ± C1) * C2 => (MDC * C2) ± (C1 * C2)
(so long as the constant-folding doesn't yield any denormal or special value)
llvm-svn: 171793
turning a code like this:
if (foo)
free(foo)
into that:
free(foo)
Move a call to free from basic block FB into FB's predecessor, P,
when the path from P to FB is taken only if the argument of free is
not equal to NULL.
Some restrictions apply on P and FB to be sure that this code motion
is profitable. Namely:
1. FB must have only one predecessor P.
2. FB must contain only the call to free plus an unconditional
branch to S.
3. P's successors are FB and S.
Because of 1., we will not increase the code size when moving the call
to free from FB to P.
Because of 2., FB will be empty after the move.
Because of 2. and 3., P's branch instruction becomes useless, so as FB
(simplifycfg will do the job).
llvm-svn: 171762
peculiar headers under include/llvm.
This struct still doesn't make a lot of sense, but it makes more sense
down in TargetLowering than it did before.
llvm-svn: 171739
already in a class, just inline the four of them. I suspect that this
class could be simplified some to not always keep distinct variables for
these things, but it wasn't clear to me how given the usage so I opted
for a trivial and mechanical translation.
This removes one of the two remaining users of a header in include/llvm
which does nothing more than define a 4 member struct.
llvm-svn: 171738
TargetTransformInfo rather than TargetLowering, removing one of the
primary instances of the layering violation of Transforms depending
directly on Target.
This is a really big deal because LSR used to be a "special" pass that
could only be tested fully using llc and by looking at the full output
of it. It also couldn't run with any other loop passes because it had to
be created by the backend. No longer is this true. LSR is now just
a normal pass and we should probably lift the creation of LSR out of
lib/CodeGen/Passes.cpp and into the PassManagerBuilder. =] I've not done
this, or updated all of the tests to use opt and a triple, because
I suspect someone more familiar with LSR would do a better job. This
change should be essentially without functional impact for normal
compilations, and only change behvaior of targetless compilations.
The conversion required changing all of the LSR code to refer to the TTI
interfaces, which fortunately are very similar to TargetLowering's
interfaces. However, it also allowed us to *always* expect to have some
implementation around. I've pushed that simplification through the pass,
and leveraged it to simplify code somewhat. It required some test
updates for one of two things: either we used to skip some checks
altogether but now we get the default "no" answer for them, or we used
to have no information about the target and now we do have some.
I've also started the process of removing AddrMode, as the TTI interface
doesn't use it any longer. In some cases this simplifies code, and in
others it adds some complexity, but I think it's not a bad tradeoff even
there. Subsequent patches will try to clean this up even further and use
other (more appropriate) abstractions.
Yet again, almost all of the formatting changes brought to you by
clang-format. =]
llvm-svn: 171735
being present. Make a member of one of the helper classes a reference as
part of this.
Reformatting goodness brought to you by clang-format.
llvm-svn: 171726
This makes the loop vectorizer match the pattern followed by roughly all
other passses. =]
Notably, this header file was braken in several regards: it contained
a using namespace directive, global #define's that aren't globaly
appropriate, and global constants defined directly in the header file.
As a side benefit, lots of the types in this file become internal, which
will cause the optimizer to chew on this pass more effectively.
llvm-svn: 171723
This could be simplified further, but Hal has a specific feature for
ignoring TTI, and so I preserved that.
Also, I needed to use it because a number of tests fail when switching
from a null TTI to the NoTTI nonce implementation. That seems suspicious
to me and so may be something that you need to look into Hal. I worked
it by preserving the old behavior for these tests with the flag that
ignores all target info.
llvm-svn: 171722
this patch brought to you by the tool clang-format.
I wanted to fix up the names of constructor parameters because they
followed a bit of an anti-pattern by naming initialisms with CamelCase:
'Tti', 'Se', etc. This appears to have been in an attempt to not overlap
with the names of member variables 'TTI', 'SE', etc. However,
constructor arguments can very safely alias members, and in fact that's
the conventional way to pass in members. I've fixed all of these I saw,
along with making some strang abbreviations such as 'Lp' be simpler 'L',
or 'Lgl' be the word 'Legal'.
However, the code I was touching had indentation and formatting somewhat
all over the map. So I ran clang-format and fixed them.
I also fixed a few other formatting or doxygen formatting issues such as
using ///< on trailing comments so they are associated with the correct
entry.
There is still a lot of room for improvement of the formating and
cleanliness of this code. ;] At least a few parts of the coding
standards or common practices in LLVM's code aren't followed, the enum
naming rules jumped out at me. I may mix some of these while I'm here,
but not all of them.
llvm-svn: 171719
I'm sorry for duplicating bad style here, but I wanted to keep
consistency. I've pinged the code review thread where this style was
reviewed and changes were requested.
llvm-svn: 171714
through as a reference rather than a pointer. There is always *some*
implementation of this available, so this simplifies code by not having
to test for whether it is available or not.
Further, it turns out there were piles of places where SimplifyCFG was
recursing and not passing down either TD or TTI. These are fixed to be
more pedantically consistent even though I don't have any particular
cases where it would matter.
llvm-svn: 171691
Michael Gottesman