llvm-svn: 224088

Updating comments to reflect the current state of the world after my recent changes to ownership structure and generally better describe what a GCStrategy is and how it works.

llvm-svn: 224086

Add an option to disable optimization to shrink truncated larger type
loads to smaller type loads. On SI this prevents using scalar load
instructions in some cases, since there are no scalar extloads.

llvm-svn: 224084

llvm-svn: 224080

llvm-svn: 224079

This was checking if pseudo-operands like the source
modifiers were using the constant bus, which happens to work
because the values these all can be happen to be valid inline
immediates.

This fixes a later commit which starts checking the register class
of the operands.

llvm-svn: 224078

`MDString`s can have arbitrary characters in them.  Prevent an assertion
that fired in `BitcodeWriter` because of sign extension by copying the
characters into the record as `unsigned char`s.

Based on a patch by Keno Fischer; fixes PR21882.

llvm-svn: 224077

llvm-svn: 224076

llvm-svn: 224075

llvm-svn: 224074

This reflects the typelessness of `Metadata` in the bitcode format,
removing types from all metadata operands.

`METADATA_VALUE` represents a `ValueAsMetadata`, and always has two
fields: the type and the value.

`METADATA_NODE` represents an `MDNode`, and unlike `METADATA_OLD_NODE`,
doesn't store types.  It stores operands at their ID+1 so that `0` can
reference `nullptr` operands.

Part of PR21532.

llvm-svn: 224073

If we have an add (or an or that is really an add), where one operand is a
FrameIndex and the other operand is a small constant, we can combine the
lowering of the FrameIndex (which is lowered as an add of the FI and a zero
offset) with the constant operand.

Amusingly, this is an old potential improvement entry from
lib/Target/PowerPC/README.txt which had never been resolved. In short, we used
to lower:

        %X = alloca { i32, i32 }
        %Y = getelementptr {i32,i32}* %X, i32 0, i32 1
        ret i32* %Y

as:

        addi 3, 1, -8
        ori 3, 3, 4
        blr

and now we produce:

        addi 3, 1, -4
        blr

which is much more sensible.

llvm-svn: 224071

I'm about to change these, so move the old ones out of the way.

Part of PR21532.

llvm-svn: 224070

llvm-svn: 224068

llvm-svn: 224067

This saves a second compare and an and / or by using
the unordered comparison instructions.

llvm-svn: 224066

llvm-svn: 224065

This commit changes the way we get fake stack from ASan runtime
(to find use-after-return errors) and the way we represent local
variables:
  - __asan_stack_malloc function now returns pointer to newly allocated
    fake stack frame, or NULL if frame cannot be allocated. It doesn't
    take pointer to real stack as an input argument, it is calculated
    inside the runtime.
  - __asan_stack_free function doesn't take pointer to real stack as
    an input argument. Now this function is never called if fake stack
    frame wasn't allocated.
  - __asan_init version is bumped to reflect changes in the ABI.
  - new flag "-asan-stack-dynamic-alloca" allows to store all the
    function local variables in a dynamic alloca, instead of the static
    one. It reduces the stack space usage in use-after-return mode
    (dynamic alloca will not be called if the local variables are stored
    in a fake stack), and improves the debug info quality for local
    variables (they will not be described relatively to %rbp/%rsp, which
    are assumed to be clobbered by function calls). This flag is turned
    off by default for now, but I plan to turn it on after more
    testing.

llvm-svn: 224062

Since `MachineInstr` is required to have a trivial destructor, it cannot
remove itself from `LeakDetection`.  Remove the calls.

As it happens, this requirement is because `MachineFunction` allocates
all `MachineInstr`s in a custom allocator; when the `MachineFunction` is
destroyed they're dropped of the edge.  There's no benefit to detecting
leaks.

llvm-svn: 224061

This gives us better leak detection messages, like `Value` has.

This also has the side effect of papering over a problem where
`MachineInstr`s are added as garbage to the leak detector and then
deleted without being removed.  If `MDNode::getTemporary()` allocates an
`MDNodeFwdDecl` in the same spot, the leak detector asserts.  By
separating `MDNode`s into their own container we lose that assertion.

Since `MachineInstr` is required to have a trivial destructor, its usage
of `LeakDetector` at all is pretty suspect.  I'll be sending a patch
soon to strip that out.

llvm-svn: 224060

Previously print+verify passes were added in a very unsystematic way, which is
annoying when debugging as you miss intermediate steps and allows bugs to stay
unnotice when no verification is performed.

To make this change practical I added the possibility to explicitely disable
verification. I used this option on all places where no verification was
performed previously (because alot of places actually don't pass the
MachineVerifier).
In the long term these problems should be fixed properly and verification
enabled after each pass. I'll enable some more verification in subsequent
commits.

This is the 2nd attempt at this after realizing that PassManager::add() may
actually delete the pass.

llvm-svn: 224059

Rather than requiring overloads in the wrapper and the impl, just
overload the impl and use templates in the wrapper.  This makes it less
error prone to add more overloads (`void *` defeats any chance the
compiler has at noticing bugs, so the easier the better).

At the same time, correct the comment that was lying about not changing
functionality for `Value`.

llvm-svn: 224058

llvm-svn: 224056

This patch teaches the instruction combiner how to fold a call to 'insertqi' if
the 'length field' (3rd operand) is set to zero, and if the sum between
field 'length' and 'bit index' (4th operand) is bigger than 64.

From the AMD64 Architecture Programmer's Manual:
1. If the sum of the bit index + length field is greater than 64, then the
   results are undefined;
2. A value of zero in the field length is defined as a length of 64.

This patch improves the existing combining logic for intrinsic 'insertqi'
adding extra checks to address both point 1. and point 2.

Differential Revision: http://reviews.llvm.org/D6583

llvm-svn: 224054

llvm-svn: 224053

As a bonus we can actually check the return value.

llvm-svn: 224046

check-llvm was failing.

llvm-svn: 224045

The static analyzer catches a few potential bugs in LLVMSupport. Add
in asserts to silence the warnings.

llvm-svn: 224044

llvm-svn: 224043

Previously print+verify passes were added in a very unsystematic way, which is
annoying when debugging as you miss intermediate steps and allows bugs to stay
unnotice when no verification is performed.

To make this change practical I added the possibility to explicitely disable
verification. I used this option on all places where no verification was
performed previously (because alot of places actually don't pass the
MachineVerifier).
In the long term these problems should be fixed properly and verification
enabled after each pass. I'll enable some more verification in subsequent
commits.

llvm-svn: 224042

llvm-svn: 224041

llvm-svn: 224036

The distinction is mostly useful in the front-end. By the time we get here,
there are very few situations where we actually want different behaviour for
Darwin and IOS (in fact Darwin mostly just exists in a few tests). So this
should reduce any surprising weirdness for anyone using it.

No functional change on anything anyone actually cares about.

llvm-svn: 224035

PPCISelDAGToDAG contained existing code to lower i32 sdiv by a power-of-2 using
srawi/addze, but did not implement the i64 case. DAGCombine now contains a
callback specifically designed for this purpose (BuildSDIVPow2), and part of
the logic has been moved to an implementation of that callback. Doing this
lowering using BuildSDIVPow2 likely does not matter, compared to handling
everything in PPCISelDAGToDAG, for the positive divisor case, but the negative
divisor case, which generates an additional negation, can potentially benefit
from additional folding from DAGCombine. Now, both the i32 and the i64 cases
have been implemented.

Fixes PR20732.

llvm-svn: 224033

llvm-svn: 224029

llvm-svn: 224028

llvm-svn: 224027

llvm-svn: 224026

This cuts down the number on system calls done by a static llvm-ar producing
lib/libclangSema.a from 9164 to 442.

llvm-svn: 224025

We already have them mapped into memory, so we can just close the file.

llvm-svn: 224020