undefs in branches/switches, we have two cases: a branch on a literal
undef or a branch on a symbolic value which is undef.  If we have a
literal undef, the code was correct: forcing it to a constant is the
right thing to do.

If we have a branch on a symbolic value that is undef, we should force
the symbolic value to a constant, which then makes the successor block
live.  Forcing the condition of the branch to being a constant isn't 
safe if later paths become live and the value becomes overdefined.  This
is the case that 'forcedconstant' is designed to handle, so just use it.

This fixes rdar://7765019 but there is no good testcase for this, the
one I have is too insane to be useful in the future.

llvm-svn: 100478

is necessary. Inherits from new templated baseclass CallSiteBase<>
which is highly customizable. Base CallSite on it too, in a configuration
that allows full mutation.
Adapt some call sites in analyses to employ ImmutableCallSite.

llvm-svn: 100100

llvm-svn: 99564

I have audited all getOperandNo calls now, fixing
hidden assumptions. CallSite related uglyness will
be eliminated successively.

Note this patch has a long and griveous history,
for all the back-and-forths have a look at
CallSite.h's log.

llvm-svn: 99399

llvm-svn: 99395

llvm-svn: 97313

of a subtle interation in a loop operating in densemap order.

llvm-svn: 97288

and T->isPointerTy().  Convert most instances of the first form to the second form.
Requested by Chris.

llvm-svn: 96344

llvm-svn: 92612

adjacent uses of a dead basic block from the same user. This fixes PR5596.

llvm-svn: 89658

blockaddress users. This fixes PR5569.

llvm-svn: 89483

tracked down by Stephan Reiter!

llvm-svn: 86726

llvm-svn: 86133

resizes in IPSCCP.  This fixes PR5394.

llvm-svn: 86036

more aggressive an correct.  This survives building llvm in 64-bit
mode with optimizations and the built llvm passes make check.

llvm-svn: 85973

llvm-svn: 85937

functions that don't have local linkage.  Basically, we need to be more
careful about propagating argument information to functions whose results
we aren't tracking.  This fixes a miscompilation of 
LLVMCConfigurationEmitter.cpp when built with an llvm-gcc that has ipsccp
enabled.

llvm-svn: 85923

to follow.

llvm-svn: 85903

llvm-svn: 85858

std::map to DenseMap, exposed on release llvm-gcc bootstrap.

llvm-svn: 85840

llvm-svn: 85818

disable it until I can fix it.

llvm-svn: 85810

function to calls of that function, regardless of whether it has local
linkage or has its address taken.  Not escaping should only affect 
whether we make an aggressive assumption about the arguments to a 
function, not whether we can track the result of it.

llvm-svn: 85795

llvm-svn: 85793

a shared place instead of duplicating it 4 times.

llvm-svn: 85792

"multiple return values" but not "first class aggregates"

llvm-svn: 85791

llvm-svn: 85790

instead of reinventing SCCP-specific logic.  This gives us
new powers.

llvm-svn: 85789

a DenseMap.  Doing this required being aware of subtle iterator
invalidation issues, but it provides a big speedup.  In a 
release-asserts build, this sped up optimizing 403.gcc from
1.34s -> 0.79s (IPSCCP) and 1.11s -> 0.44s (SCCP).

This commit also conflates in a bunch of general cleanups, sorry.

llvm-svn: 85788

an assertion on the buildbot.

llvm-svn: 85784

simplify some code.

llvm-svn: 85783

llvm-svn: 85780

llvm-svn: 85778

llvm-svn: 85777

function, eliminate temporary (and pointless) smallvector.

llvm-svn: 85776

llvm-svn: 85775

llvm-svn: 85774

llvm-svn: 85773

in a way that should prevent ip constprop.  This allows clang/test/CodeGen/indirect-goto.c
to pass with the new indirect goto lowering.

llvm-svn: 85709

crash on any clang tests.

llvm-svn: 85465