Commit Graph

8 Commits

Author SHA1 Message Date
Duncan P. N. Exon Smith c8eccd1147 verify-uselistorder: Force -preserve-bc-use-list-order
llvm-svn: 216022
2014-08-19 21:08:27 +00:00
Duncan P. N. Exon Smith 852e00e3d1 verify-uselistorder: Change the default -num-shuffles=5
Change the default for `-num-shuffles` to 5 and better document the
algorithm in the header docs of `verify-uselistorder`.

llvm-svn: 214419
2014-07-31 18:46:24 +00:00
Duncan P. N. Exon Smith a12e023c8a Rename llvm-uselistorder => verify-uselistorder
llvm-svn: 214318
2014-07-30 17:11:27 +00:00
Duncan P. N. Exon Smith 3f0fc7bca9 Bitcode: Correctly compare a Use against itself
Fix the sort of expected order in the reader to correctly return `false`
when comparing a `Use` against itself.

This was caught by test/Bitcode/binaryIntInstructions.3.2.ll, so I'm
adding a `RUN` line using `llvm-uselistorder` for every test in
`test/Bitcode` that passes.

A few tests still fail, so I'll investigate those next.

This is part of PR5680.

llvm-svn: 214157
2014-07-29 01:13:56 +00:00
Duncan P. N. Exon Smith fee1f5013c Fix line-endings, NFC
A follow-up commit is adding a RUN line to each of these tests, so fix
the line endings first.  This is a whitespace-only change.

llvm-svn: 214156
2014-07-29 01:10:57 +00:00
Tim Northover 420a216817 IR: add "cmpxchg weak" variant to support permitted failure.
This commit adds a weak variant of the cmpxchg operation, as described
in C++11. A cmpxchg instruction with this modifier is permitted to
fail to store, even if the comparison indicated it should.

As a result, cmpxchg instructions must return a flag indicating
success in addition to their original iN value loaded. Thus, for
uniformity *all* cmpxchg instructions now return "{ iN, i1 }". The
second flag is 1 when the store succeeded.

At the DAG level, a new ATOMIC_CMP_SWAP_WITH_SUCCESS node has been
added as the natural representation for the new cmpxchg instructions.
It is a strong cmpxchg.

By default this gets Expanded to the existing ATOMIC_CMP_SWAP during
Legalization, so existing backends should see no change in behaviour.
If they wish to deal with the enhanced node instead, they can call
setOperationAction on it. Beware: as a node with 2 results, it cannot
be selected from TableGen.

Currently, no use is made of the extra information provided in this
patch. Test updates are almost entirely adapting the input IR to the
new scheme.

Summary for out of tree users:
------------------------------

+ Legacy Bitcode files are upgraded during read.
+ Legacy assembly IR files will be invalid.
+ Front-ends must adapt to different type for "cmpxchg".
+ Backends should be unaffected by default.

llvm-svn: 210903
2014-06-13 14:24:07 +00:00
Tim Northover e94a518a22 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

llvm-svn: 203559
2014-03-11 10:48:52 +00:00
Michael Kuperstein 661e288a70 Ensure bitcode encoding of instructions and their operands stays stable.
This includes instructions that relate to memory access (load/store/GEP), comparison instructions and calls.

Work was done by lama.saba@intel.com.

llvm-svn: 202647
2014-03-02 15:26:36 +00:00