If any def of a machine-sink candidate has local uses, it's obviously not safe to sink it to a successor block. This bug has been hidden because a later check for critical-edge disable these illegal

If any def of a machine-sink candidate has local uses, it's obviously not safe to sink it to a successor block. This bug has been hidden because a later check for critical-edge disable these illegal optimizations. This patch should significantly reduce the amount of time spent on checking dominator information for obviously unsafe sinking.

llvm-svn: 111450

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Reapply r110396, with fixes to appease the Linux buildbot gods.

llvm-svn: 110460

Revert r110396 to fix buildbots.

llvm-svn: 110410

Don't use PassInfo* as a type identifier for passes. Instead, use the address of the static
ID member as the sole unique type identifier. Clean up APIs related to this change.

llvm-svn: 110396

Fix batch of converting RegisterPass<> to INTIALIZE_PASS().

llvm-svn: 109045

- Reapply r106066 now that the bzip2 build regression has been fixed.
- 2010-06-25-CoalescerSubRegDefDead.ll is the testcase for r106878.

llvm-svn: 106880

Revert r106066, "Create a more targeted fix for not sinking instructions into a range where it"... it causes bzip2 to be miscompiled by Clang.

Conflicts:

lib/CodeGen/MachineSink.cpp

llvm-svn: 106

Revert r106066, "Create a more targeted fix for not sinking instructions into a range where it"... it causes bzip2 to be miscompiled by Clang.

Conflicts:

lib/CodeGen/MachineSink.cpp

llvm-svn: 106614

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Improve comment to include that the use of a preg is also verboten in this situation.

llvm-svn: 106119

Create a more targeted fix for not sinking instructions into a range where it
will conflict with another live range. The place which creates this scenerio is
the code in X86 that lowers a select inst

Create a more targeted fix for not sinking instructions into a range where it
will conflict with another live range. The place which creates this scenerio is
the code in X86 that lowers a select instruction by splitting the MBBs. This
eliminates the need to check from the bottom up in an MBB for live pregs.

llvm-svn: 106066

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Cleanup 80-column and trim trailing whitespace

llvm-svn: 105435

Machine sink could potentially sink instructions into a block where the physical
registers it defines then interfere with an existing preg live range.

For instance, if we had something like these ma

Machine sink could potentially sink instructions into a block where the physical
registers it defines then interfere with an existing preg live range.

For instance, if we had something like these machine instructions:

BB#0
... = imul ... EFLAGS<imp-def,dead>
test ..., EFLAGS<imp-def>
jcc BB#2 EFLAGS<imp-use>

BB#1
... ; fallthrough to BB#2

BB#2
... ; No code that defines EFLAGS
jcc ... EFLAGS<imp-use>

Machine sink will come along, see that imul implicitly defines EFLAGS, but
because it's "dead", it assumes that it can move imul into BB#2. But when it
does, imul's "dead" imp-def of EFLAGS is raised from the dead (a zombie) and
messes up the condition code for the jump (and pretty much anything else which
relies upon it being correct).

The solution is to know which pregs are live going into a basic block. However,
that information isn't calculated at this point. Nor does the LiveVariables pass
take into account non-allocatable physical registers. In lieu of this, we do a
*very* conservative pass through the basic block to determine if a preg is live
coming out of it.

llvm-svn: 105387

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Compulsive reformating. No functionalitical changes.

llvm-svn: 105359

Teach MachineLICM and MachineSink how to clear kill flags conservatively
when they move instructions.

llvm-svn: 103737

Avoid sinking machine instructions into a loop.

MachineLoopInfo is already available when MachineSinking runs, so the check is
free.

There is no test case because it would require a critical edge i

Avoid sinking machine instructions into a loop.

MachineLoopInfo is already available when MachineSinking runs, so the check is
free.

There is no test case because it would require a critical edge into a loop, and
CodeGenPrepare splits those. This check is just to be extra careful.

llvm-svn: 101420

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Teach MachineSinking to handle easy critical edges.

Sometimes it is desirable to sink instructions along a critical edge:

x = ...
if (a && b) ...
else use(x);

The 'a && b' condition creates a crit

Teach MachineSinking to handle easy critical edges.

Sometimes it is desirable to sink instructions along a critical edge:

x = ...
if (a && b) ...
else use(x);

The 'a && b' condition creates a critical edge to the else block, but we still
want to sink the computation of x into the block. The else block is dominated by
the parent block, so we are not pushing instructions into new code paths.

llvm-svn: 101165

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Don't do code sinking on unreachable blocks. It's unprofitable and hazardous.

llvm-svn: 100455

Fix some more places where dbg_value affected codegen.

llvm-svn: 97765

Swap parameters of isSafeToMove and isSafeToReMat for consistency.

llvm-svn: 97578

move target-independent opcodes out of TargetInstrInfo
into TargetOpcodes.h. #include the new TargetOpcodes.h
into MachineInstr. Add new inline accessors (like isPHI())
to MachineInstr, and start u

move target-independent opcodes out of TargetInstrInfo
into TargetOpcodes.h. #include the new TargetOpcodes.h
into MachineInstr. Add new inline accessors (like isPHI())
to MachineInstr, and start using them throughout the
codebase.

llvm-svn: 95687

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Change errs() to dbgs().

llvm-svn: 92593

Remove includes of Support/Compiler.h that are no longer needed after the
VISIBILITY_HIDDEN removal.

llvm-svn: 85043

Remove VISIBILITY_HIDDEN from class/struct found inside anonymous namespaces.
Chris claims we should never have visibility_hidden inside any .cpp file but
that's still not true even after this commit

Remove VISIBILITY_HIDDEN from class/struct found inside anonymous namespaces.
Chris claims we should never have visibility_hidden inside any .cpp file but
that's still not true even after this commit.

llvm-svn: 85042

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Fix a typo in a comment.

llvm-svn: 84504

Change a few instance variables to be local variables.

llvm-svn: 84503

Factor out LiveIntervalAnalysis' code to determine whether an instruction
is trivially rematerializable and integrate it into
TargetInstrInfo::isTriviallyReMaterializable. This way, all places that
n

Factor out LiveIntervalAnalysis' code to determine whether an instruction
is trivially rematerializable and integrate it into
TargetInstrInfo::isTriviallyReMaterializable. This way, all places that
need to know whether an instruction is rematerializable will get the
same answer.

This enables the useful parts of the aggressive-remat option by
default -- using AliasAnalysis to determine whether a memory location
is invariant, and removes the questionable parts -- rematting operations
with virtual register inputs that may not be live everywhere.

llvm-svn: 83687

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