llvm-svn: 164940

is the second time I've moved this comment around...)

llvm-svn: 164939

llvm-svn: 164938

alignment requirements of the new alloca. As one consequence which was
reported as a bug by Duncan, we overaligned memcpy calls to ranges of
allocas after they were rewritten to types with lower alignment
requirements. Other consquences are possible, but I don't have any test
cases for them.

llvm-svn: 164937

llvm-svn: 164935

Fixes PR13985.

llvm-svn: 164934

could probably be factored still further to hoist this logic into
a generic helper, but currently I don't have particularly clean ideas
about how to handle that.

This at least allows us to drop custom load rewriting from the
speculation logic, which in turn allows the existing load rewriting
logic to fire. In theory, this could enable vector promotion or other
tricks after speculation occurs, but I've not dug into such issues. This
is primarily just cleaning up the factoring of the code and the
resulting logic.

llvm-svn: 164933

Lookup can nevertheless find them due to the serialized lookup table.
For instance when reading a template decl's templatedDecl, it will search for existing decls that it could be a redeclaration of, and find the half-read template decl.
Thus there is no point in asserting the names of decls.

llvm-svn: 164932

Don't require specializations (of existing and read template) to be unique.

llvm-svn: 164931

Also move one of them from grep to FileCheck.
Patch from Joey Gouly <joey.gouly@arm.com>!

llvm-svn: 164929

llvm-svn: 164928

Bring ASTReader and Writer into sync for the case where a canonical template specialization was written, which is non-canonical at the time of reading: force the reading of the ClassTemplateDecl if it was written.
The easiest way out is to store whether the decl was canonical at the time of writing.
Add test.

llvm-svn: 164927

llvm-svn: 164926

a pair of instructions, one for the used pointer and the second for the
user. This simplifies the representation and also makes it more dense.

This was noticed because of the miscompile in PR13926. In that case, we
were running up against a fundamental "bad idea" in the speculation of
PHI and select instructions: the speculation and rewriting are
interleaved, which requires phi speculation to also perform load
rewriting! This is bad, and causes us to miss opportunities to do (for
example) vector rewriting only exposed after PHI speculation, etc etc.
It also, in the old system, required us to insert *new* load uses into
the current partition's use list, which would then be ignored during
rewriting because we had already extracted an end iterator for the use
list. The appending behavior (and much of the other oddities) stem from
the strange de-duplication strategy in the PartitionUse builder.
Amusingly, all this went without notice for so long because it could
only be triggered by having *different* GEPs into the same partition of
the same alloca, where both different GEPs were operands of a single
PHI, and where the GEP which was not encountered first also had multiple
uses within that same PHI node... Hence the insane steps required to
reproduce.

So, step one in fixing this fundamental bad idea is to make the
PartitionUse actually contain a Use*, and to make the builder do proper
deduplication instead of funky de-duplication. This is enough to remove
the appending behavior, and fix the miscompile in PR13926, but there is
more work to be done here. Subsequent commits will lift the speculation
into its own visitor. It'll be a useful step toward potentially
extracting all of the speculation logic into a generic utility
transform.

The existing PHI test case for repeated operands has been made more
extreme to catch even these issues. This test case, run through the old
pass, will exactly reproduce the miscompile from PR13926. ;] We were so
close here!

llvm-svn: 164925

No functionality change.

llvm-svn: 164924

SimplifyCFG: Enumerating all predecessors of a BB can be expensive (switches), avoid it if possible.

No functionality change.

llvm-svn: 164923

llvm-svn: 164922

bad.  Fonts already have appropriate tracking built-in.

llvm-svn: 164921

llvm-svn: 164920

Change getX86SubSuperRegister to take an MVT::SimpleValueType rather than an EVT and add llvm_unreachable to the switches. Helps it compile to dramatically better code.

llvm-svn: 164919

Fun fact: The CBE learned how to deal with this situation before it was removed.

llvm-svn: 164918

CodeGen: Copy tail padding when we're not dealing with a trivial copy assign or move assign operator.

This fixes a regression from r162254, the optimizer has problems reasoning
about the smaller memcpy as it's often not safe to widen a store but making it
smaller is.

llvm-svn: 164917

llvm-svn: 164916

llvm-svn: 164915

source of false positives due to globals being declared in a header with some
kind of incomplete (small) type, but the actual definition being bigger.

llvm-svn: 164912

llvm-svn: 164911

A DAGCombine optimization for merging consecutive stores. This optimization is not profitable in many cases
because moden processos can store multiple values in parallel, and preparing the consecutive store requires
some work.  We only handle these cases:

1. Consecutive stores where the values and consecutive loads. For example:
 int a = p->a;
 int b = p->b;
 q->a = a;
 q->b = b;

2. Consecutive stores where the values are constants. Foe example:
 q->a = 4;
 q->b = 5;

llvm-svn: 164910

llvm-svn: 164909

llvm-svn: 164908

llvm-svn: 164907

llvm-svn: 164906

llvm-svn: 164905

llvm-svn: 164904

llvm-svn: 164903

llvm-svn: 164902

llvm-svn: 164900

llvm-svn: 164899

llvm-svn: 164898

llvm-svn: 164897

broken as of r164656 as TemplateArgument::getAsDecl() now asserts
instead of returning NULL for other template arugment kinds.

llvm-svn: 164896