Commit Graph

15987 Commits

Author SHA1 Message Date
Jakob Stoklund Olesen
7824152557 Only update regunit live ranges that have been precomputed.
Regunit live ranges are computed on demand, so when mi-sched calls
handleMove, some regunits may not have live ranges yet.

That makes updating them easier: Just skip the non-existing ranges. They
will be computed correctly from the rescheduled machine code when they
are needed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158831 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-20 18:00:57 +00:00
Chandler Carruth
305b515c27 Remove 'static' from inline functions defined in header files.
There is a pretty staggering amount of this in LLVM's header files, this
is not all of the instances I'm afraid. These include all of the
functions that (in my build) are used by a non-static inline (or
external) function. Specifically, these issues were caught by the new
'-Winternal-linkage-in-inline' warning.

I'll try to just clean up the remainder of the clearly redundant "static
inline" cases on functions (not methods!) defined within headers if
I can do so in a reliable way.

There were even several cases of a missing 'inline' altogether, or my
personal favorite "static bool inline". Go figure. ;]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158800 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-20 08:39:33 +00:00
Andrew Trick
37aa33bc11 A new algorithm for computing LoopInfo. Temporarily disabled.
-stable-loops enables a new algorithm for generating the Loop
forest. It differs from the original algorithm in a few respects:

- Not determined by use-list order.
- Initially guarantees RPO order of block and subloops.
- Linear in the number of CFG edges.
- Nonrecursive.

I didn't want to change the LoopInfo API yet, so the block lists are
still inclusive. This seems strange to me, and it means that building
LoopInfo is not strictly linear, but it may not be a problem in
practice. At least the block lists start out in RPO order now. In the
future we may add an attribute or wrapper analysis that allows other
passes to assume RPO order.

The primary motivation of this work was not to optimize LoopInfo, but
to allow reproducing performance issues by decomposing the compilation
stages. I'm often unable to do this with the current LoopInfo, because
the loop tree order determines Loop pass order. Serializing the IR
tends to invert the order, which reverses the optimization order. This
makes it nearly impossible to debug interdependent loop optimizations
such as LSR.

I also believe this will provide more stable performance results across time.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158790 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-20 05:23:33 +00:00
Andrew Trick
cbf24b4e58 Move the implementation of LoopInfo into LoopInfoImpl.h.
The implementation only needs inclusion from LoopInfo.cpp and
MachineLoopInfo.cpp. Clients of the interface should only include the
interface. This makes the interface readable and speeds up rebuilds
after modifying the implementation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158787 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-20 03:42:09 +00:00
Nick Kledzik
ca077ec5ea Add permissions(), map_file_pages(), and unmap_file_pages() to llvm::sys::fs and add unit test. Unix is implemented. Windows side needs to be implemented.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158770 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-20 00:28:54 +00:00
Chad Rosier
2531a6415f Add an ensureMaxAlignment() function to MachineFrameInfo (analogous to
ensureAlignment() in MachineFunction).  Also, drop setMaxAlignment() in
favor of this new function.  This creates a main entry point to setting
MaxAlignment, which will be helpful for future work.  No functionality
change intended.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158758 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-19 22:59:12 +00:00
Lang Hames
d693cafcfb Add DAG-combines for aggressive FMA formation.
This patch adds DAG combines to form FMAs from pairs of FADD + FMUL or
FSUB + FMUL. The combines are performed when:
(a) Either
      AllowExcessFPPrecision option (-enable-excess-fp-precision for llc)
        OR
      UnsafeFPMath option (-enable-unsafe-fp-math)
    are set, and
(b) TargetLoweringInfo::isFMAFasterThanMulAndAdd(VT) is true for the type of
    the FADD/FSUB, and
(c) The FMUL only has one user (the FADD/FSUB).

If your target has fast FMA instructions you can make use of these combines by
overriding TargetLoweringInfo::isFMAFasterThanMulAndAdd(VT) to return true for
types supported by your FMA instruction, and adding patterns to match ISD::FMA
to your FMA instructions.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158757 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-19 22:51:23 +00:00
Chad Rosier
f54469f7fc Typo. Patch by Cameron McInally <cameron.mcinally@nyu.edu>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158754 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-19 22:28:18 +00:00
Rafael Espindola
d6b43a317e Move the support for using .init_array from ARM to the generic
TargetLoweringObjectFileELF. Use this to support it on X86. Unlike ARM,
on X86 it is not easy to find out if .init_array should be used or not, so
the decision is made via TargetOptions and defaults to off.

Add a command line option to llc that enables it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158692 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-19 00:48:28 +00:00
Nuno Lopes
f6fc855a00 revert r158660, since Chris has some issues with this patch (namely using code to reprent information only used by the compiler)
Original commit msg:
add the 'alloc' metadata node to represent the size of offset of buffers pointed to by pointers.
This metadata can be attached to any instruction returning a pointer


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158688 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-18 23:34:26 +00:00
David Blaikie
9042010596 Don't copy a potentially-uninitialized variable.
Based on review discussion of r158638 with Chandler Carruth, Tobias von Koch, and Duncan Sands and a -Wmaybe-uninitialized warning from GCC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158685 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-18 22:31:28 +00:00
Hal Finkel
e877c4f9c7 Allow up to 64 functional units per processor itinerary.
This patch changes the type used to hold the FU bitset from unsigned to uint64_t.
This will be needed for some upcoming PowerPC itineraries.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158679 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-18 21:08:18 +00:00
Marshall Clow
9ac0f1d725 Added accessors for getting coff_relocation info
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158675 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-18 19:47:16 +00:00
Nuno Lopes
fa7494306b add the 'alloc' metadata node to represent the size of offset of buffers pointed to by pointers.
This metadata can be attached to any instruction returning a pointer


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158660 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-18 16:04:04 +00:00
Benjamin Kramer
d45f7b6b5d Bring the return value of SmallVector::insert in line with std::vector::insert.
It always returns the iterator for the first inserted element, or the passed in
iterator if the inserted range was empty. Flesh out the unit test more and fix
all the cases it uncovered so far.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158645 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-17 12:46:13 +00:00
Chandler Carruth
b4bec53f36 Remove SmallMap, and the several files that were used to implement it.
We have SmallDenseMap now that has more correct and predictable
semantics, even though it is a more narrow abstraction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158644 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-17 12:07:42 +00:00
Benjamin Kramer
5f6c7cfa93 SmallVector: return a valid iterator for the rare case of inserting an empty range into a SmallVector.
Patch by Johannes Schaub!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158643 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-17 11:52:22 +00:00
Chandler Carruth
8dffa4a106 Add a unit test for 'swap', and fix a pile of bugs in
SmallDenseMap::swap.

First, make it parse cleanly. Yay for uninstantiated methods.

Second, make the inline-buckets case work correctly. This is way
trickier than it should be due to the uninitialized values in empty and
tombstone buckets.

Finally fix a few typos that caused construction/destruction mismatches
in the counting unittest.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158641 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-17 11:28:13 +00:00
Chandler Carruth
6446d7e6d6 Add tests for *DenesMap for both key and value types' construction and
destruction and fix a bug in SmallDenseMap they caught.

This is kind of a poor-man's version of the testing that just adds the
addresses to a set on construction and removes them on destruction. We
check that double construction and double destruction don't occur.
Amusingly enough, this is enough to catch a lot of SmallDenseMap issues
because we spend a lot of time with fixed stable addresses in the inline
buffer.

The SmallDenseMap bug fix included makes grow() not double-destroy in
some cases. It also fixes a FIXME there, the code was pretty crappy. We
now don't have any wasted initialization, but we do move the entries in
inline bucket array an extra time. It's probably a better tradeoff, and
is much easier to get correct.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158639 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-17 10:33:51 +00:00
Chandler Carruth
dd9d38d57b Introduce a SmallDenseMap container that re-uses the existing DenseMap
implementation.

This type includes an inline bucket array which is used initially. Once
it is exceeded, an array of 64 buckets is allocated on the heap. The
bucket count grows from there as needed. Some highlights of this
implementation:

- The inline buffer is very carefully aligned, and so supports types
  with alignment constraints.
- It works hard to avoid aliasing issues.
- Supports types with non-trivial constructors, destructors, copy
  constructions, etc. It works reasonably hard to minimize copies and
  unnecessary initialization. The most common initialization is to set
  keys to the empty key, and so that should be fast if at all possible.

This class has a performance / space trade-off. It tries to optimize for
relatively small maps, and so packs the inline bucket array densely into
the object. It will be marginally slower than a normal DenseMap in a few
use patterns, so it isn't appropriate everywhere.

The unit tests for DenseMap have been generalized a bit to support
running over different map implementations in addition to different
key/value types. They've then been automatically extended to cover the
new container through the magic of GoogleTest's typed tests.

All of this is still a bit rough though. I'm going to be cleaning up
some aspects of the implementation, documenting things better, and
adding tests which include non-trivial types. As soon as I'm comfortable
with the correctness, I plan to switch existing users of SmallMap over
to this class as it is already more correct w.r.t. construction and
destruction of objects iin the map.

Thanks to Benjamin Kramer for all the reviews of this and the lead-up
patches. That said, more review on this would really be appreciated. As
I've noted a few times, I'm quite surprised how hard it is to get the
semantics for a hashtable-based map container with a small buffer
optimization correct. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158638 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-17 09:05:09 +00:00
Benjamin Kramer
a978366339 Guard private fields that are unused in Release builds with #ifndef NDEBUG.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158608 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-16 21:48:13 +00:00
Hal Finkel
7b4ff9343d Move the Metadata merging methods from GVN and make them public in MDNode.
There are other passes, BBVectorize specifically, that also need some of
this functionality.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158605 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-16 20:33:37 +00:00
Benjamin Kramer
904cf82f27 Merge the SmallBitVector and BitVector unit tests with gtest's typed test magic and bring SmallBitVector up to date.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158600 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-16 10:51:07 +00:00
Chandler Carruth
585de7a1b1 Add support to the alignment support header for conjuring a character
array of a suitable size and alignment for any of a number of different
types to be stored into the character array.

The mechanisms for producing an explicitly aligned type are fairly
complex because this operation is poorly supported on all compilers.
We've spent a fairly significant amount of time experimenting with
different implementations inside of Google, and the one using explicitly
expanded templates has been the most robust.

Credit goes to Nick Lewycky for writing the first 20 versions or so of
this logic we had inside of Google. I based this on the only one to
actually survive. In case anyone is worried, yes we are both explicitly
re-contributing and re-licensing it for LLVM. =]

Once the issues with actually specifying the alignment are finished, it
turns out that most compilers don't in turn align anything the way they
are instructed. Testing of this logic against both Clang and GCC
indicate that the alignment constraints are largely ignored by both
compilers! I've come up with and used a work-around by wrapping each
alignment-hinted type directly in a struct, and using that struct to
align the character array through a union. This elaborate hackery is
terrifying, but I've included testing that caught a terrifying number of
bugs in every other technique I've tried.

All of this in order to implement a poor C++98 programmers emulation of
C++11 unrestricted unions in classes such as SmallDenseMap.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158597 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-16 08:52:57 +00:00
Chandler Carruth
48f4dcf0f7 Lift the NumElements and NumTombstones members into the super class
rather than the base class. Add a pile of boilerplate to indirect around
this.

This is pretty ugly, but it allows the super class to change the
representation of these values, which will be key for doing
a SmallDenseMap.

Suggestions on better method structuring / naming are welcome, but keep
in mind that SmallDenseMap won't have an 'unsigned' member to expose
a reference to... =/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158586 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-16 01:18:07 +00:00
Chandler Carruth
7f6c82a7e0 Factor DenseMap into a base class that implements the hashtable logic,
and a derived class that provides the allocation and growth strategy.

This is the first (and biggest) step toward building a SmallDenseMap
that actually behaves exactly the same as DenseMap, and supports all the
same types and interface points with the same semantics.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158585 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-16 01:05:01 +00:00
Marshall Clow
d4d03e09d3 Adding acessors to COFFObjectFile so that clients can get at the (non-generic) bits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158484 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-15 01:08:25 +00:00
Rafael Espindola
0397729d3b Implement the isSafeToDiscardIfUnused predicate and use it in globalopt and
globaldce. Globaldce was already removing linkonce globals, but globalopt was
not.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158476 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-14 22:48:13 +00:00
Stepan Dyatkovskiy
cba91230c0 SmallMap, FlatArrayMap::copyFrom
Replaced memcpy with std::copy, since the first one may work improperly with non POD data.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158457 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-14 16:59:43 +00:00
Chandler Carruth
14d81c416c Group the 'unsigned' members after the pointer to avoid 4 bytes of
padding on x86-64.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158421 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-13 21:44:07 +00:00
Kay Tiong Khoo
575e90e955 *typo: Cyles changed to Cycles
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158404 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-13 15:53:04 +00:00
Duncan Sands
ee5a094ccf When linearizing a multiplication, return at once if we see a factor of zero,
since then the entire expression must equal zero (similarly for other operations
with an absorbing element).  With this in place a bunch of reassociate code for
handling constants is dead since it is all taken care of when linearizing.  No
intended functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158398 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-13 09:42:13 +00:00
Craig Topper
cc95b57d42 Fix intrinsics for XOP frczss/sd instructions. These instructions only take one source register and zero the upper bits of the destination rather than preserving them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158396 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-13 07:18:53 +00:00
Jakob Stoklund Olesen
764dc754fe Eliminate struct TableGenBackend.
TableGen backends are simply written as functions now.

Patch by Sean Silva!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158389 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-13 05:15:49 +00:00
Andrew Trick
9df55eed04 sched: Avoid trivially redundant DAG edges. Take the one with higher latency.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158379 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-13 02:39:00 +00:00
David Blaikie
b9c592f4c5 Remove use of GNU extension to resolve Clang warning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158364 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-12 17:06:32 +00:00
Duncan Sands
c038a78335 Now that Reassociate's LinearizeExprTree can look through arbitrary expression
topologies, it is quite possible for a leaf node to have huge multiplicity, for
example: x0 = x*x, x1 = x0*x0, x2 = x1*x1, ... rapidly gives a value which is x
raised to a vast power (the multiplicity, or weight, of x).  This patch fixes
the computation of weights by correctly computing them no matter how big they
are, rather than just overflowing and getting a wrong value.  It turns out that
the weight for a value never needs more bits to represent than the value itself,
so it is enough to represent weights as APInts of the same bitwidth and do the
right overflow-avoiding dance steps when computing weights.  As a side-effect it
reduces the number of multiplies needed in some cases of large powers.  While
there, in view of external uses (eg by the vectorizer) I made LinearizeExprTree
static, pushing the rank computation out into users.  This is progress towards
fixing PR13021.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158358 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-12 14:33:56 +00:00
Argyrios Kyrtzidis
3e61374295 Satisfy C++ aliasing rules, per suggestion by Chandler.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158346 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-12 01:06:16 +00:00
Argyrios Kyrtzidis
793537d21f For llvm::sys::ThreadLocalImpl instead of malloc'ing the platform-specific
thread local data, embed them in the class using a uint64_t and make sure
we get compiler errors if there's a platform where this is not big enough.

This makes ThreadLocal more safe for using it in conjunction with CrashRecoveryContext.

Related to crash in rdar://11434201.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158342 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-12 00:21:31 +00:00
Andrew Trick
0eb3a3524e misched: When querying RegisterPressureTracker, always save current and max pressure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158340 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-11 23:42:23 +00:00
Jakob Stoklund Olesen
6f36fa981a Write llvm-tblgen backends as functions instead of sub-classes.
The TableGenBackend base class doesn't do much, and will be removed
completely soon.

Patch by Sean Silva!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158311 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-11 15:37:55 +00:00
Jakob Stoklund Olesen
20aedcdfa3 Fix a problem with the reverse bundle iterators.
This showed up the first time rend() was called on a bundled instruction
in the Mips backend.

Also avoid dereferencing end() in bundle_iterator::operator++().

We still don't have a place to put unit tests for this stuff.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158310 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-11 15:11:12 +00:00
Craig Topper
cfd3ed9eaf Add intrinsics for immediate form of XOP vprot instructions. Use i128mem instead of f128mem for integer XOP instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158291 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-10 07:31:56 +00:00
Craig Topper
c29106b36f Replace XOP vpcom intrinsics with fewer intrinsics that take the immediate as an argument.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158278 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-09 16:46:13 +00:00
Benjamin Kramer
82ce516591 Hashing: Remove outdated comment. Support for reserved hash values was removed in r151865.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158276 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-09 15:33:28 +00:00
Andrew Trick
ba17293a88 Register pressure: added getPressureAfterInstr.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158256 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-09 02:16:58 +00:00
Jakob Stoklund Olesen
8879480ed7 Sketch a LiveRegMatrix analysis pass.
The LiveRegMatrix represents the live range of assigned virtual
registers in a Live interval union per register unit. This is not
fundamentally different from the interference tracking in RegAllocBase
that both RABasic and RAGreedy use.

The important differences are:

- LiveRegMatrix tracks interference per register unit instead of per
  physical register. This makes interference checks cheaper and
  assignments slightly more expensive. For example, the ARM D7 reigster
  has 24 aliases, so we would check 24 physregs before assigning to one.
  With unit-based interference, we check 2 units before assigning to 2
  units.

- LiveRegMatrix caches regmask interference checks. That is currently
  duplicated functionality in RABasic and RAGreedy.

- LiveRegMatrix is a pass which makes it possible to insert
  target-dependent passes between register allocation and rewriting.
  Such passes could tweak the register assignments with interference
  checking support from LiveRegMatrix.

Eventually, RABasic and RAGreedy will be switched to LiveRegMatrix.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158255 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-09 02:13:10 +00:00
Dmitri Gribenko
77592fe39c Convert comments to proper Doxygen comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158248 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-09 00:01:45 +00:00
Andrew Trick
dddc1cf50b Removing strange "using" declarations form TargetInstrInfo.
I can't imagine why these were added. Trial and error.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158247 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-08 23:56:26 +00:00
Jakob Stoklund Olesen
05ec712e7f Reintroduce VirtRegRewriter.
OK, not really. We don't want to reintroduce the old rewriter hacks.

This patch extracts virtual register rewriting as a separate pass that
runs after the register allocator. This is possible now that
CodeGen/Passes.cpp can configure the full optimizing register allocator
pipeline.

The rewriter pass uses register assignments in VirtRegMap to rewrite
virtual registers to physical registers, and it inserts kill flags based
on live intervals.

These finalization steps are the same for the optimizing register
allocators: RABasic, RAGreedy, and PBQP.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158244 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-08 23:44:45 +00:00