loads and stores.

llvm-svn: 163844

llvm-svn: 163817

This is common when storing to global variables.

llvm-svn: 163809

llvm-svn: 163808

Use Nick's suggestion of storing a large NULL into the GV instead of memset, which requires TargetData.

llvm-svn: 163799

* wrap code blocks in \code ... \endcode;
* refer to parameter names in paragraphs correctly (\arg is not what most
  people want -- it starts a new paragraph).

llvm-svn: 163790

This function writes out the current values of the counters and then resets
them. This can be used similarly to the __gcov_flush function to sync the
counters when need be. For instance, in a situation where the application
doesn't exit.
<rdar://problem/12185886>

llvm-svn: 163757

llvm-svn: 163739

to the default target.

llvm-svn: 163724

"#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)"

No functional change. Update r163344.

llvm-svn: 163679

a pair of switch/branch where both depend on the value of the same variable and
the default case of the first switch/branch goes to the second switch/branch.

Code clean up and fixed a few issues:
1> handling the case where some cases of the 2nd switch are invalidated
2> correctly calculate the weight for the 2nd switch when it is a conditional eq

Testing case is modified from Alastair's original patch.

llvm-svn: 163635

llvm-svn: 163593

Add a pass that renames everything with metasyntatic names. This works well after using bugpoint to reduce the confusion presented by the original names, which no longer mean what they used to.

llvm-svn: 163592

llvm-svn: 163503

llvm-svn: 163491

llvm-svn: 163485

llvm-svn: 163480

Patch and test case by Alastair Murray!

llvm-svn: 163437

llvm-svn: 163378

No functional change.

llvm-svn: 163344

The lookup tables did not get built in a deterministic order.
This makes them get built in the order that the corresponding phi nodes
were found.

llvm-svn: 163305

This adds a transformation to SimplifyCFG that attemps to turn switch
instructions into loads from lookup tables. It works on switches that
are only used to initialize one or more phi nodes in a common successor
basic block, for example:

  int f(int x) {
    switch (x) {
    case 0: return 5;
    case 1: return 4;
    case 2: return -2;
    case 5: return 7;
    case 6: return 9;
    default: return 42;
  }

This speeds up the code by removing the hard-to-predict jump, and
reduces code size by removing the code for the jump targets.

llvm-svn: 163302

No functional change.

llvm-svn: 163279

llvm-svn: 163258

llvm-svn: 163205

llvm-svn: 163199

pointers-to-strong-pointers may be in play. These can lead to retains and
releases happening in unstructured ways, foiling the optimizer. This fixes
rdar://12150909.

llvm-svn: 163180

llvm-svn: 163179

Doesn't set MadeChange to TRUE if BypassSlowDivision doesn't change anything.

llvm-svn: 163165

Also a few minor changes:
- use pre-inc instead of post-inc
- use isa instead of dyn_cast
- 80 col
- trailing spaces

llvm-svn: 163164

- CodeGenPrepare pass for identifying div/rem ops
- Backend specifies the type mapping using addBypassSlowDivType
- Enabled only for Intel Atom with O2 32-bit -> 8-bit
- Replace IDIV with instructions which test its value and use DIVB if the value
is positive and less than 256.
- In the case when the quotient and remainder of a divide are used a DIV
and a REM instruction will be present in the IR. In the non-Atom case
they are both lowered to IDIVs and CSE removes the redundant IDIV instruction,
using the quotient and remainder from the first IDIV. However,
due to this optimization CSE is not able to eliminate redundant
IDIV instructions because they are located in different basic blocks.
This is overcome by calculating both the quotient (DIV) and remainder (REM)
in each basic block that is inserted by the optimization and reusing the result
values when a subsequent DIV or REM instruction uses the same operands.
- Test cases check for the presents of the optimization when calculating
either the quotient, remainder,  or both.

Patch by Tyler Nowicki!

llvm-svn: 163150

Scan the body of the loop and find instructions that may trap.
Use this information when deciding if it is safe to hoist or sink instructions.
Notice that we can optimize the search of instructions that may throw in the case of nested loops.

rdar://11518836

llvm-svn: 163132

For example, the ARM target does not have efficient ISel handling for vector
selects with scalar conditions. This patch adds a TLI hook which allows the
different targets to report which selects are supported well and which selects
should be converted to CF duting codegen prepare.

llvm-svn: 163093

We update until we hit a fixpoint. This is probably slow but also
slightly simplifies the code. It should also fix the occasional
invalid domtrees observed when building with expensive checking.

I couldn't find a case where this had a measurable slowdown, but
if someone finds a pathological case where it does we may have
to find a cleverer way of updating dominators here.

Thanks to Duncan for the test case.

llvm-svn: 163091

Most of the code guarded with ANDROIDEABI are not
ARM-specific, and having no relation with arm-eabi.
Thus, it will be more natural to call this
environment "Android" instead of "ANDROIDEABI".

Note: We are not using ANDROID because several projects
are using "-DANDROID" as the conditional compilation
flag.

llvm-svn: 163087

llvm-svn: 163058

llvm-svn: 162914

The old PHI updating code in loop-rotate was replaced with SSAUpdater a while
ago, it has no problems with comples PHIs. What had to be fixed is detecting
whether a loop was already rotated and updating dominators when multiple exits
were present.

This change increases overall code size a bit, mostly due to additional loop
unrolling opportunities. Passes test-suite and selfhost with -verify-dom-info.
Fixes PR7447.

Thanks to Andy for the input on the domtree updating code.

llvm-svn: 162912

llvm-svn: 162911

llvm-svn: 162907