Commit Graph

7 Commits

Author SHA1 Message Date
Tim Northover
5c8b83eb7a X86: expand atomics in IR instead of as MachineInstrs.
The logic for expanding atomics that aren't natively supported in
terms of cmpxchg loops is much simpler to express at the IR level. It
also allows the normal optimisations and CodeGen improvements to help
out with atomics, instead of using a limited set of possible
instructions..

rdar://problem/13496295

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212119 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-01 18:53:31 +00:00
Tim Northover
ca396e391e IR: add a second ordering operand to cmpxhg for failure
The syntax for "cmpxchg" should now look something like:

	cmpxchg i32* %addr, i32 42, i32 3 acquire monotonic

where the second ordering argument gives the required semantics in the case
that no exchange takes place. It should be no stronger than the first ordering
constraint and cannot be either "release" or "acq_rel" (since no store will
have taken place).

rdar://problem/15996804

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203559 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-11 10:48:52 +00:00
NAKAMURA Takumi
17020de0e9 llvm/test/CodeGen/X86: Unmark them out of XFAIL:cygming, in atomic{32|64}.ll and handle-move.ll, corresponding to r178549.
This reverts r176808, r176798, and r177914.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178583 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-02 22:35:08 +00:00
NAKAMURA Takumi
15e8583814 llvm/test/CodeGen/X86/atomic{32|64}.ll: Unmark them out of XFAIL:win32.
I know it is incorrect and they'd fail with +Asserts for win32 targets, though.
I'll try to fix them tonight.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177914 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-25 21:07:53 +00:00
NAKAMURA Takumi
be15cdda54 Suppress atomic(32|64).ll as XFAIL on win32 codegen. Investigating.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176798 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-11 08:39:48 +00:00
Michael Liao
c537f79dcd Fix PR15355
- Clear 'mayStore' flag when loading from the atomic variable before the
  spin loop
- Clear kill flag from one use to multiple use in registers forming the
  address to that atomic variable
- don't use a physical register as live-in register in BB (neither entry
  nor landing pad.) by copying it into virtual register

(patch by Cameron Zwarich)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176538 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-06 00:17:04 +00:00
Michael Liao
b118a073d7 Re-work X86 code generation of atomic ops with spin-loop
- 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.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164281 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-20 03:06:15 +00:00