When a linkonce_odr value that is on the dso list is not unnamed_addr
we can still look to see if anything is actually using its address. If
not, it is safe to hide it.

This patch implements that by moving GlobalStatus to Transforms/Utils
and using it in Internalize.

llvm-svn: 193090

Found while adding type safety to the various DWARF enumerations (form,
attribute, tag, etc) that caused Clang to warn on an incompletely
covered switch. Converting the comment to a default/unreachable
uncovered this case of an unsupported form encoding. Seems we were
skipping fission strings entirely.

llvm-svn: 193089

llvm-svn: 193083

llvm-svn: 193082

llvm-svn: 193081

llvm-svn: 193080

These instructions are logically related as they allow read/write of MSA control registers.
Currently MSA control registers are emitted by number but hopefully that will change as soon 
as GAS starts accepting them by name as that would make the assembly easier to read.

llvm-svn: 193078

llvm-svn: 193077

The second parameter of the SLD intrinsic is the number of columns (GPR) to 
slide left the source array.

llvm-svn: 193076

Additionally some small comment/stylistic fixes are included as well.

llvm-svn: 193068

A landing pad can be jumped to only by the unwind edge of an invoke
instruction. If we eliminate a partially redundant load in a landing pad, it
will create a basic block that violates this constraint. It then leads to other
problems down the line if it tries to merge that basic block with the landing
pad. Avoid this by not eliminating the load in a landing pad.

PR17621

llvm-svn: 193064

llvm-svn: 193063

One optimization simplify-cfg performs is the converting of switches to
lookup tables if the switch has > 4 cases. This is done by:

1. Finding the max/min case value and calculating the switch case range.
2. Create a lookup table basic block.
3. Perform a check in the switch's BB to see if the input value is in
the switch's case range. If the input value satisfies said predicate
branch to the lookup table BB, otherwise branch to the switch's default
destination BB using the default value as the result.

The conditional check consists of subtracting the min case value of the
table from any input iN value and then ensuring that said value is
unsigned less than the size of the lookup table represented as an iN
value.

If the lookup table is a covered lookup table, the size of the table will be N
which is 0 as an iN value. Thus the comparison will be an `icmp ult` of an iN
value against 0 which is always false yielding the incorrect result.

This patch fixes this problem by recognizing if we have a covered lookup table
and if we do, unconditionally jumps to the lookup table BB since the covering
property of the lookup table implies no input values could not be handled by
said BB.

rdar://15268442

llvm-svn: 193045

llvm-svn: 193043

This ensures that the prefix data is treated as part of the function for
the purpose of debug info.  This provides a better debugging experience,
among other things by allowing a debug info client to correctly look up
a function in debug info given a function pointer.

llvm-svn: 193042

r182712 attempted to do this, but it failed to handle data emitted via
EmitBytes.

llvm-svn: 193041

llvm-svn: 193038

If the predecessor's being spliced into a landing pad, then we need the PHIs to
come first and the rest of the predecessor's code to come *after* the landing
pad instruction.

llvm-svn: 193035

llvm-svn: 193034

llvm-svn: 193033

llvm-svn: 193031

llvm-svn: 193024

llvm-svn: 193023

llvm-svn: 193021

SCEV currently fails to compute loop counts for nonunit stride
loops. This comes up frequently. It prevents loop optimization and
forces vectorization to insert extra loop checks.

For example:
void foo(int n, int *x) {
 for (int i = 0; i < n; i += 3) {
   x[i] = i;
   x[i+1] = i+1;
   x[i+2] = i+2;
 }
}

We need to properly handle the case in which limit > INT_MAX-stride. In
the above case: n > INT_MAX-3. In this case the loop counter will step
beyond the limit and overflow at the same time. However, knowing that
signed integer overlow in undefined, we can assume the loop test
behavior is arbitrary after overflow. This obeys both C undefined
behavior rules, and the more strict LLVM poison value rules.

I'm finally fixing this in response to Hal Finkel's persistence.
The most probable reason that we never optimized this before is that
we were being careful to handle case where the developer expected a
side-effect free infinite loop relying on overflow:

for (int i = 0; i < n; i += s) {
  ++j;
}
return j;

If INT_MAX+1 is a multiple of s and n > INT_MAX-s, then we might
expect an infinite loop. However there are plenty of ways to achieve
this effect without relying on undefined behavior of signed overflow.

llvm-svn: 193015

llvm-svn: 193014

llvm-svn: 193013

llvm-svn: 193012

llvm-svn: 193011

llvm-svn: 193009

Update to reflect current GC APIs and usage. The example code is taken from the Erlang GC implementation.

llvm-svn: 193008

llvm-svn: 193007

llvm-svn: 193004

With this commit, all DIEs created in CompileUnit will be added to parents
inside the same function. Also make getOrCreateTemplateType|Value functions
private.

No functionality change.

llvm-svn: 193002

llvm-svn: 193001

This is another (final?) stab at making us able to parse our own asm output
on Windows.

Symbols on Windows often contain @'s and ?'s in their names. Our asm parser
didn't like this. ?'s were not allowed, and @'s were intepreted as trying to
reference PLT/GOT/etc.

We can't just add quotes around the bad names, since e.g. for MinGW, we use gas
to assemble, and it doesn't like quotes in some places (notably in .def
directives).

This commit makes us allow ?'s in symbol names, and @'s in symbol names for MS
assembly.

Differential Revision: http://llvm-reviews.chandlerc.com/D1978

llvm-svn: 193000

Thanks to Milan Lenčo for noticing it.

llvm-svn: 192996

error messages should not be able to occur at the same time.

llvm-svn: 192985

Forgot to 'svn add'

llvm-svn: 192978

Patch by Artyom Skrobov.

llvm-svn: 192977