when an initializer is variable (I handled the constant case in a previous
patch).  This has three pieces:

1. Enhance AggValueSlot to have a 'isZeroed' bit to tell CGExprAgg that
   the memory being stored into has previously been memset to zero.
2. Teach CGExprAgg to not emit stores of zero to isZeroed memory.
3. Teach CodeGenFunction::EmitAggExpr to scan initializers to determine
   whether they are profitable to emit a memset + inividual stores vs
   stores for everything.

The heuristic used is that a global has to be more than 16 bytes and
has to be 3/4 zero to be candidate for this xform.  The two testcases
are illustrative of the scenarios this catches.  We now codegen test9 into:

 call void @llvm.memset.p0i8.i64(i8* %0, i8 0, i64 400, i32 4, i1 false)
 %.array = getelementptr inbounds [100 x i32]* %Arr, i32 0, i32 0
 %tmp = load i32* %X.addr, align 4
 store i32 %tmp, i32* %.array

and test10 into:

  call void @llvm.memset.p0i8.i64(i8* %0, i8 0, i64 392, i32 8, i1 false)
  %tmp = getelementptr inbounds %struct.b* %S, i32 0, i32 0
  %tmp1 = getelementptr inbounds %struct.a* %tmp, i32 0, i32 0
  %tmp2 = load i32* %X.addr, align 4
  store i32 %tmp2, i32* %tmp1, align 4
  %tmp5 = getelementptr inbounds %struct.b* %S, i32 0, i32 3
  %tmp10 = getelementptr inbounds %struct.a* %tmp5, i32 0, i32 4
  %tmp11 = load i32* %X.addr, align 4
  store i32 %tmp11, i32* %tmp10, align 4

Previously we produced 99 stores of zero for test9 and also tons for test10.
This xforms should substantially speed up -O0 builds when it kicks in as well
as reducing code size and optimizer heartburn on insane cases.  This resolves
PR279.

llvm-svn: 120692

llvm-svn: 120688

rdar://8560647

llvm-svn: 120650

llvm-svn: 120646

a global is larger than 32 bytes and has fewer than 6 non-zero values in the
initializer.  Previously we'd turn something like this:

char test8(int X) {
  char str[10000] = "abc";

into a 10K global variable which we then memcpy'd from.  Now we generate:

  %str = alloca [10000 x i8], align 16
  %tmp = getelementptr inbounds [10000 x i8]* %str, i64 0, i64 0
  call void @llvm.memset.p0i8.i64(i8* %tmp, i8 0, i64 10000, i32 16, i1 false)
  store i8 97, i8* %tmp, align 16
  %0 = getelementptr [10000 x i8]* %str, i64 0, i64 1
  store i8 98, i8* %0, align 1
  %1 = getelementptr [10000 x i8]* %str, i64 0, i64 2
  store i8 99, i8* %1, align 2

Which is much smaller in space and also likely faster.

This is part of PR279

llvm-svn: 120645

into the latter.

llvm-svn: 120643

Check for compatible gcc, Altivec and Neon vectors before handling the
lax-vector-conversions case.  Otherwise there is no way to avoid the
warnings from -Wvector-conversions.

llvm-svn: 120633

to be available in debug vs. release builds.

llvm-svn: 120629

llvm-svn: 120628

definition of an Objective-C class. Unlike with C/C++ classes, we
don't have a well-defined point in Sema where Objective-C classes are
checked for completeness, nor do we need to involve Sema when
completing a class. Therefore, we take the appropriate of having the
external AST source mark a particular Objective-C class as having an
external declaration; when using one of the accessors of an
Objective-C class that has an external declaration, we request that
the external AST source fill in the Objective-C class definition.

llvm-svn: 120627

to be used in copy helper synthesis of __block
variables. wip.

llvm-svn: 120617

to 'assumeXXX'.

llvm-svn: 120614

llvm-svn: 120613

llvm-svn: 120610

'evalXXX'.

llvm-svn: 120609

conversions. Previously, we would end up collapsing qualification
conversions into the Objective-C pointer conversion step, including
(possibly) stripping qualifiers that shouldn't be removed.

This generalizes BuildSimilarlyQualifiedPointerType() to also work on
Objective-C object pointers, then eliminates the (redundant, not
totally correct) BuildSimilarlyQualifiedObjCObjectPointerType()
function.

Fixes <rdar://problem/8714395>.

llvm-svn: 120607

reflects what the class actually does.

llvm-svn: 120605

instantiations, GCC also supports "inline" and "static" explicit
template instantiations. Parse and warn about such constructs, but
don't implement the semantics of either "inline" or "static". They
don't seem to be widely used.

llvm-svn: 120599

llvm-svn: 120588

disambiguate between an expression (for a bit-field width) and a type
(for a fixed underlying type). Since the disambiguation can be
expensive (due to tentative parsing), we perform a simplistic
disambiguation based on one-token lookahead before going into the
full-blown tentative parsing. Based on a patch by Daniel Wallin.

llvm-svn: 120582

redeclaration of an enum type differs from that of the original
declaration, from Daniel Wallin

llvm-svn: 120577

AST printing for scoped enumerations and enumerations with a fixed underlying type, from Daniel Wallin

llvm-svn: 120576

llvm-svn: 120562

llvm-svn: 120555

llvm-svn: 120554

llvm-svn: 120545

llvm-svn: 120544

specified a syntactically invalid path, it's better to let the OS
diagnose the problem than to silently skip it.

llvm-svn: 120542

http://llvm.org/bugs/show_bug.cgi?id=279#c3 better.

No functionality change yet.

llvm-svn: 120530

llvm-svn: 120528

using ConstantInt::get.

llvm-svn: 120527

llvm-svn: 120523

'Class' type, disgnostic should refere to a
class method. Fixes // rdar://8592156

llvm-svn: 120517

refer to opaque types, they must be held via PATypeHolders.  I'm
not sure why this hasn't blown up before.

llvm-svn: 120491

llvm-svn: 120489

literal declaration caused crash in CodeGen.
This patch fixes it. pr8707

llvm-svn: 120486

Follow through references to catch returned stack addresses, local blocks, label addresses or references to temporaries, e.g:

const int& g2() {
  int s1;
  int &s2 = s1; // expected-note {{binding reference variable 's2' here}}
  return s2; // expected-warning {{reference to stack memory associated with local variable 's1' returned}}
}

llvm-svn: 120483

declarations.

llvm-svn: 120448

llvm-svn: 120446

llvm-svn: 120433