[C++11] Add 'override' keyword to virtual methods that override their base class.

llvm-svn: 203220

MachineCopyPropagation has special logic for removing COPY instructions. It will remove plain COPYs using eraseFromParent(), but if the COPY has imp-defs/imp-uses it will convert it to a KILL, to kee

MachineCopyPropagation has special logic for removing COPY instructions. It will remove plain COPYs using eraseFromParent(), but if the COPY has imp-defs/imp-uses it will convert it to a KILL, to keep the imp-def around.

This actually totally breaks and causes the machine verifier to cry in several cases, one of which being:

%RAX<def> = COPY %RCX<kill>
%ECX<def> = COPY %EAX<kill>, %RAX<imp-use,kill>

These subregister copies are together identified as noops, so are both removed. However, the second one as it has an imp-use gets converted into a kill:

%ECX<def> = KILL %EAX<kill>, %RAX<imp-use,kill>

As the original COPY has been removed, the verifier goes into tears at the use of undefined EAX and RAX.

There are several hacky solutions to this hacky problem (which is all to do with imp-use/def weirdnesses), but the least hacky I've come up with is to *always* remove COPYs by converting to KILLs. KILLs are no-ops to the code generator so the generated code doesn't change (which is why they were partially used in the first place), but using them also keeps the def/use and imp-def/imp-use chains alive:

%RAX<def> = KILL %RCX<kill>
%ECX<def> = KILL %EAX<kill>, %RAX<imp-use,kill>

The patch passes all test cases including the ones that check the removal of MOVs in this circumstance, along with an extra test I added to check subregister behaviour (which made the machine verifier fall over before my patch).

The patch also adds some DEBUG() statements because the file hadn't got any.

llvm-svn: 199797

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Simplify logic now that r182490 is in place. No functional change intended.

llvm-svn: 182531

Use the new script to sort the includes of every file under lib.

Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module

Use the new script to sort the includes of every file under lib.

Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

llvm-svn: 169131

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Convert COPY instructions into KILLs if they have implicit defs.

MachineCopyPropagation doesn't understand super-register liveness well
enough to be able to remove implicit defs of super-registers.

Convert COPY instructions into KILLs if they have implicit defs.

MachineCopyPropagation doesn't understand super-register liveness well
enough to be able to remove implicit defs of super-registers.

This fixes a problem in ARM/2012-01-26-CopyPropKills.ll that is exposed
by an future TwoAddressInstructionPass change. The KILL instructions are
removed before the machine code is emitted.

llvm-svn: 169060

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Remove unneeded #include.

llvm-svn: 168664

Switch most getReservedRegs() clients to the MRI equivalent.

Using the cached bit vector in MRI avoids comstantly allocating and
recomputing the reserved register bit vector.

llvm-svn: 165983

Switch all register list clients to the new MC*Iterator interface.

No functional change intended.

Sorry for the churn. The iterator classes are supposed to help avoid
giant commits like this one in

Switch all register list clients to the new MC*Iterator interface.

No functional change intended.

Sorry for the churn. The iterator classes are supposed to help avoid
giant commits like this one in the future. The TableGen-produced
register lists are getting quite large, and it may be necessary to
change the table representation.

This makes it possible to do so without changing all clients (again).

llvm-svn: 157854

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Switch some getAliasSet clients to MCRegAliasIterator.

MCRegAliasIterator can optionally visit the register itself, allowing
for simpler code.

llvm-svn: 157837

Use a SmallVector and linear lookup instead of a DenseSet - SourceMap values
will always be tiny sets, so DenseSet is overkill (SmallSet won't work as we
need iteration support).

llvm-svn: 153529

During MachineCopyPropagation a register may be the source operand of multiple
copies being considered for removal. Make sure to track all of the copies,
rather than just the most recent encountered,

During MachineCopyPropagation a register may be the source operand of multiple
copies being considered for removal. Make sure to track all of the copies,
rather than just the most recent encountered, by holding a DenseSet instead of
an unsigned in SrcMap.

No test case - couldn't reduce something with a sane size.

llvm-svn: 153487

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Convert more GenRegisterInfo tables from unsigned to uint16_t to reduce static data size.

llvm-svn: 152016

Use uint16_t to store register overlaps to reduce static data.

llvm-svn: 152001

Fix for PR12090: clear def maps of aliases when visiting a copy. e.g.
%S5<def> = COPY %S0<kill>
First clear def map of Q1, etc.

No small test case available.

llvm-svn: 151574

Fix machine-cp by having it to check sub-register indicies. e.g.
ecx = mov eax
al = mov ch
The second copy is not a nop because the sub-indices of ecx,ch is not the
same of that of eax/al.

Re-enabl

Fix machine-cp by having it to check sub-register indicies. e.g.
ecx = mov eax
al = mov ch
The second copy is not a nop because the sub-indices of ecx,ch is not the
same of that of eax/al.

Re-enabled machine-cp.
PR11940

llvm-svn: 151002

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Erase dead copies that are clobbered by a call.

This does make a difference, at least when using RABasic.

llvm-svn: 150118

Handle register masks in MachineCopyPropagation.

For simplicity, treat calls with register masks as basic block
boundaries. This means we can't copy propagate callee-saved registers
across calls, b

Handle register masks in MachineCopyPropagation.

For simplicity, treat calls with register masks as basic block
boundaries. This means we can't copy propagate callee-saved registers
across calls, but I don't think that is a big deal.

llvm-svn: 150108

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Codegen pass definition cleanup. No functionality.

Moving toward a uniform style of pass definition to allow easier target configuration.
Globally declare Pass ID.
Globally declare pass initializer.

Codegen pass definition cleanup. No functionality.

Moving toward a uniform style of pass definition to allow easier target configuration.
Globally declare Pass ID.
Globally declare pass initializer.
Use INITIALIZE_PASS consistently.
Add a call to the initializer from CodeGen.cpp.
Remove redundant "createPass" functions and "getPassName" methods.

While cleaning up declarations, cleaned up comments (sorry for large diff).

llvm-svn: 150100

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whitespace

llvm-svn: 150094

Clear kill flags before propagating a copy.

The live range of the source register may be extended when a redundant
copy is eliminated. Make sure any kill flags between the two copies are
cleared.

T

Clear kill flags before propagating a copy.

The live range of the source register may be extended when a redundant
copy is eliminated. Make sure any kill flags between the two copies are
cleared.

This fixes PR11765.

llvm-svn: 149069

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Avoid eraseing copies from a reserved register unless the definition can be
safely proven not to have been clobbered. No small test case possible.

llvm-svn: 147751

Added a late machine instruction copy propagation pass. This catches
opportunities that only present themselves after late optimizations
such as tail duplication .e.g.
## BB#1:
movl %eax,

Added a late machine instruction copy propagation pass. This catches
opportunities that only present themselves after late optimizations
such as tail duplication .e.g.
## BB#1:
movl %eax, %ecx
movl %ecx, %eax
ret

The register allocator also leaves some of them around (due to false
dep between copies from phi-elimination, etc.)

This required some changes in codegen passes. Post-ra scheduler and the
pseudo-instruction expansion passes have been moved after branch folding
and tail merging. They were before branch folding before because it did
not always update block livein's. That's fixed now. The pass change makes
independently since we want to properly schedule instructions after
branch folding / tail duplication.

rdar://10428165
rdar://10640363

llvm-svn: 147716

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