There are two things out of the ordinary in this commit. First, I made
a loop obviously "infinite" in HexagonInstrInfo.cpp. After checking if
an instruction was at the beginning of a basic block (in which case,
`break`), the loop decremented and checked the iterator for `nullptr` as
the loop condition. This has never been possible (the prev pointers are
always been circular, so even with the weird ilist/iplist
implementation, this isn't been possible), so I removed the condition.
Second, in HexagonAsmPrinter.cpp there was another case of comparing a
`MachineBasicBlock::instr_iterator` against `MachineBasicBlock::end()`
(which returns `MachineBasicBlock::iterator`). While not incorrect,
it's fragile. I switched this to `::instr_end()`.
All that said, no functionality change intended here.
llvm-svn: 250778
This reverts commit r250592.
It has issues around unevaluated contexts, like this:
template <class T> struct A { T i; };
template <class T>
struct B : A<T> {
using A<T>::i;
typedef decltype(i) U;
};
template struct B<int>;
llvm-svn: 250774
This makes LLDB launch and create a REPL, specifying no target so that the REPL
can create one for itself. Also added the "--repl-language" option, which
specifies the language to use. Plumbed the relevant arguments and errors
through the REPL creation mechanism.
llvm-svn: 250773
m_directory = "/tmp"
m_filename = "."
To look like:
m_directory = "/tmp/."
m_filename = "foo.txt"
if "foo.txt" was appended to it. With this fix it will be:
m_directory = "/tmp"
m_filename = "foo.txt"
llvm-svn: 250770
This patch was generating by running `2to3` on the files in the
lldb/test directory. This patch should be NFC, but it does
introduce the `from __future__ import print_function` line, which
will break future uses of the print statement.
llvm-svn: 250763
Out-of-line definitions of static data members which have an inline
initializer must get GVA_DiscardableODR linkage instead of
GVA_StrongExternal linkage.
MSVC 2013's behavior is different with respect to this and would cause
link errors if one TU provided a definition while another did not.
MSVC 2015 fixed this bug, making this OK. Note that the 2015 behavior
is always compatible with 2013: it never produces a strong definition.
This essentially reverts r237787.
llvm-svn: 250757
Currently, in MachineBlockPlacement pass the loop is rotated to let the best exit to be the last BB in the loop chain, to maximize the fall-through from the loop to outside. With profile data, we can determine the cost in terms of missed fall through opportunities when rotating a loop chain and select the best rotation. Basically, there are three kinds of cost to consider for each rotation:
1. The possibly missed fall through edge (if it exists) from BB out of the loop to the loop header.
2. The possibly missed fall through edges (if they exist) from the loop exits to BB out of the loop.
3. The missed fall through edge (if it exists) from the last BB to the first BB in the loop chain.
Therefore, the cost for a given rotation is the sum of costs listed above. We select the best rotation with the smallest cost. This is only for PGO mode when we have more precise edge frequencies.
Differential revision: http://reviews.llvm.org/D10717
llvm-svn: 250754
A REPL takes over the command line and typically treats input as source code.
REPLs can also do code completion. The REPL class allows its subclasses to
implement the language-specific functionality without having to know about the
IOHandler-specific internals.
Also added a PluginManager-based way of getting to a REPL given a language and
a target.
Also brought in some utility code and expression options that are useful for
REPLs, such as line offsets for expressions, ANSI terminal coloring of errors,
and a few IOHandler convenience functions.
llvm-svn: 250753
In r248047, I attempted to fix a build breakage introduced by using
llvm's regex support from lldb-mi. However, my approach was flawed
when LLVM and lldb are dynamically linked, in which case two copies
of LLVMSupport would end up in memory, causing crashes on lldb start up.
Instead, use LINK_COMPONENTS to make sure lldb-mi has access to the
LLVMSupport symbols without causing duplication in the dynamic library
case.
llvm-svn: 250751
As usual, this is a polymorphic hierarchy without polymorphic ownership,
so simply make the dtor protected non-virtual, protected default copy
ctor/assign, and make derived classes final. The derived classes will
pick up correct default public copy ops (and dtor) implicitly.
(wish I could add -Wdeprecated to the build, but last time I tried it
triggered on some system headers I still need to look into/figure out)
llvm-svn: 250747
Allow LLVM to optimize the sequence like the following:
%inc = add nsw i32 %i, 1
%cmp = icmp slt %n, %inc
into:
%cmp = icmp sle i32 %n, %i
The case is not handled previously due to the complexity of compuation of %n.
Hence, LLVM cannot swap operands of icmp accordingly.
llvm-svn: 250746
Besides the usual, I finally added an overload to
`BasicBlock::splitBasicBlock()` that accepts an `Instruction*` instead
of `BasicBlock::iterator`. Someone can go back and remove this overload
later (after updating the callers I'm going to skip going forward), but
the most common call seems to be
`BB->splitBasicBlock(BB->getTerminator(), ...)` and I'm not sure it's
better to add `->getIterator()` to every one than have the overload.
It's pretty hard to get the usage wrong.
llvm-svn: 250745
This was originally checked in at r250527, but reverted at r250570 because of PR25222.
There were at least 2 problems:
1. The cost check was checking for an instruction with an exact cost of TCC_Expensive;
that should have been >=.
2. The cause of the clang stage 1 failures was illegally sinking 'call' instructions;
we can't sink instructions that may have side effects / are not safe to execute speculatively.
Fixed those conditions in sinkSelectOperand() and added test cases.
Original commit message:
This is a follow-up to the discussion in D12882.
Ideally, we would like SimplifyCFG to be able to form select instructions even when the operands
are expensive (as defined by the TTI cost model) because that may expose further optimizations.
However, we would then like a later pass like CodeGenPrepare to undo that transformation if the
target would likely benefit from not speculatively executing an expensive op (this patch).
Once we have this safety mechanism in place, we can adjust SimplifyCFG to restore its
select-formation behavior that changed with r248439.
Differential Revision: http://reviews.llvm.org/D13297
llvm-svn: 250743
The two names are similar enough that they might lead to confusion.
The output of readobj clarifies but I missed it when I originally
committed this. Found while linking FreeBSD userland with lld.
llvm-svn: 250739
This allows open source MacOSX clients to not have to build debugserver and the current LLDB can find debugserver inside the selected Xcode.app on your system.
<rdar://problem/23167253>
llvm-svn: 250735
Given the name, it is natural for this function to compute the full target.
This will simplify SHF_MERGE handling by allowing getLocalRelTarget to
centralize the addend logic.
llvm-svn: 250731