Commit Graph

3 Commits

Author SHA1 Message Date
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
fe87c302aa Add missing i8 max/min/umax/umin support
- Fix PR5145 and turn on test 8-bit atomic ops



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164358 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-21 03:18:52 +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