X86 doesn't have i8 cmovs so isel would emit a branch. Emitting branches at this
level is often not a good idea because it's too late for many optimizations to
kick in. This solution doesn't add any extensions (truncs are free) and tries
to avoid introducing partial register stalls by filtering direct copyfromregs.

I'm seeing a ~10% speedup on reading a random .png file with libpng15 via
graphicsmagick on x86_64/westmere, but YMMV depending on the microarchitecture.

llvm-svn: 165868

llvm-svn: 165747

Add in the first iteration of support for llvm/clang/lldb to allow variable per address space pointer sizes to be optimized correctly.

llvm-svn: 165726

It broke stage2 clang and test-suite/MultiSource/Benchmarks/mediabench/g721/g721encode.

llvm-svn: 165692

llvm-svn: 165677

Original message:

The attached is the fix to radar://11663049. The optimization can be outlined by following rules:

   (select (x != c), e, c) -> select (x != c), e, x),
   (select (x == c), c, e) -> select (x == c), x, e)
where the <c> is an integer constant.

 The reason for this change is that : on x86, conditional-move-from-constant needs two instructions;
however, conditional-move-from-register need only one instruction.

  While the LowerSELECT() sounds to be the most convenient place for this optimization, it turns out to be a bad place. The reason is that by replacing the constant <c> with a symbolic value, it obscure some instruction-combining opportunities which would otherwise be very easy to spot. For that reason, I have to postpone the change to last instruction-combining phase.

  The change passes the test of "make check-all -C <build-root/test" and "make -C project/test-suite/SingleSource".

llvm-svn: 165661

- Due to the current matching vector elements constraints in
  ISD::FP_ROUND, rounding from v2f64 to v4f32 (after legalization from
  v2f32) is scalarized. Add a customized v2f32 widening to convert it
  into a target-specific X86ISD::VFPROUND to work around this
  constraints.

llvm-svn: 165631

- Due to the current matching vector elements constraints in ISD::FP_EXTEND,
  rounding from v2f32 to v2f64 is scalarized. Add a customized v2f32 widening
  to convert it into a target-specific X86ISD::VFPEXT to work around this
  constraints. This patch also reverts a previous attempt to fix this issue by
  recovering the scalarized ISD::FP_EXTEND pattern and thus significantly
  reduces the overhead of supporting non-power-2 vector FP extend.

llvm-svn: 165625

llvm-svn: 165568

We use the enums to query whether an Attributes object has that attribute. The
opaque layer is responsible for knowing where that specific attribute is stored.

llvm-svn: 165488

llvm-svn: 165402

a pointer to a type, in order to remove the uses of getGlobalContext().

Patch by Tyler Nowicki.

llvm-svn: 165255

- Add 'HwEncoding' for X86 registers and call getEncodingValue() to
  retrieve their encoding values.
- This's the first step to adopt new scheme. Furthur revising is onging.

llvm-svn: 165241

llvm-svn: 165205

llvm-svn: 165182

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

The hasFnAttr method has been replaced by querying the Attributes explicitly. No
intended functionality change.

llvm-svn: 164725

- Turn on atomic6432.ll and add specific test case as well

llvm-svn: 164616

Fix an illegal tailcall opt where the callee returns a double via xmm while caller returns x86_fp80 via st0. rdar://12229511

llvm-svn: 164588

- Fix PR5145 and turn on test 8-bit atomic ops

llvm-svn: 164358

- Rewirte most atomic instructions in templates for both better
  maintenance and future extensions, such as HLE in TSX.

llvm-svn: 164357

- Rewrite/merge pseudo-atomic instruction emitters to address the
  following issue:
  * Reduce one unnecessary load in spin-loop

    previously the spin-loop looks like

        thisMBB:
        newMBB:
          ld  t1 = [bitinstr.addr]
          op  t2 = t1, [bitinstr.val]
          not t3 = t2  (if Invert)
          mov EAX = t1
          lcs dest = [bitinstr.addr], t3  [EAX is implicit]
          bz  newMBB
          fallthrough -->nextMBB

    the 'ld' at the beginning of newMBB should be lift out of the loop
    as lcs (or CMPXCHG on x86) will load the current memory value into
    EAX. This loop is refined as:

        thisMBB:
          EAX = LOAD [MI.addr]
        mainMBB:
          t1 = OP [MI.val], EAX
          LCMPXCHG [MI.addr], t1, [EAX is implicitly used & defined]
          JNE mainMBB
        sinkMBB:

  * Remove immopc as, so far, all pseudo-atomic instructions has
    all-register form only, there is no immedidate operand.

  * Remove unnecessary attributes/modifiers in pseudo-atomic instruction
    td

  * Fix issues in PR13458

- Add comprehensive tests on atomic ops on various data types.
  NOTE: Some of them are turned off due to missing functionality.

- Revise tests due to the new spin-loop generated.

llvm-svn: 164281

This was only an issue if sse is disabled.

llvm-svn: 163967

llvm-svn: 163835

- Enhance the fix to PR12312 to support wider integer, such as 256-bit
  integer. If more than 1 fully evaluated vectors are found, POR them
  first followed by the final PTEST.

llvm-svn: 163832

    
- BlockAddress has no support of BA + offset form and there is no way to
  propagate that offset into machine operand;
- Add BA + offset support and a new interface 'getTargetBlockAddress' to
  simplify target block address forming;
- All targets are modified to use new interface and X86 backend is enhanced to
  support BA + offset addressing.

llvm-svn: 163743

llvm-svn: 163682

llvm-svn: 163596

llvm-svn: 163547

    
- Fix an remaining issue of PR11674 as well

llvm-svn: 163528

- If a boolean value is generated from CMOV and tested as boolean value,
  simplify the use of test result by referencing the original condition.
  RDRAND intrinisc is one of such cases.

llvm-svn: 163516

The VPSHUFB 256-bit instruction may be generated when one of input vector is undefined or zeroinitializer.
I've added the "zeroinitializer" case in this patch.

llvm-svn: 163506

llvm-svn: 163473

llvm-svn: 163463

llvm-svn: 163461

Set operation action for FFLOOR to Expand for all vector types for X86. Set FFLOOR of v4f32 to Expand for ARM. v2f64 was already correct.

llvm-svn: 163458

Added generation of VPSHUB instruction for <32 x i8> vector shuffle when possible.

llvm-svn: 163312

llvm-svn: 163295

Use iPTR instead of i32 for extract_subvector/insert_subvector index in lowering and patterns. This makes it consistent with the incoming DAG nodes from the DAG builder.

llvm-svn: 163293

llvm-svn: 163258