llvm/test/Transforms/SimplifyCFG, branch stable

Don't remove a landing pad if the invoke requires a table entry.

2013-03-11T20:53:00Z

An invoke may require a table entry. For instance, when the function it calls is expected to throw. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176827 91177308-0d34-0410-b5e6-96231b3b80d8

SimplifyCFG fix for volatile load/store.

2013-03-07T01:03:35Z

Fixes rdar:13349374. Volatile loads and stores need to be preserved even if the language standard says they are undefined. "volatile" in this context means "get out of the way compiler, let my platform handle it". Additionally, this is the only way I know of with llvm to write to the first page (when hardware allows) without dropping to assembly. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176599 91177308-0d34-0410-b5e6-96231b3b80d8

Use references to attribute groups on the call/invoke instructions.

2013-02-22T09:09:42Z

Listing all of the attributes for the callee of a call/invoke instruction is way too much and makes the IR unreadable. Use references to attributes instead. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175877 91177308-0d34-0410-b5e6-96231b3b80d8

Filecheckized 2x tests in SimplifyCFG and removed their date prefix to fit with current llvm style for test names.

2013-01-31T01:04:23Z

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174011 91177308-0d34-0410-b5e6-96231b3b80d8

Re-revert r173342, without losing the compile time improvements, flat

2013-01-27T06:42:03Z

out bug fixes, or functionality preserving refactorings. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173610 91177308-0d34-0410-b5e6-96231b3b80d8

Switch this code away from Value::isUsedInBasicBlock. That code either

2013-01-25T05:40:09Z

loops over instructions in the basic block or the use-def list of the value, neither of which are really efficient when repeatedly querying about values in the same basic block. What's more, we already know that the CondBB is small, and so we can do a much more efficient test by counting the uses in CondBB, and seeing if those account for all of the uses. Finally, we shouldn't blanket fail on any such instruction, instead we should conservatively assume that those instructions are part of the cost. Note that this actually fixes a bug in the pass because isUsedInBasicBlock has a really terrible bug in it. I'll fix that in my next commit, but the fix for it would make this code suddenly take the compile time hit I thought it already was taking, so I wanted to go ahead and migrate this code to a faster & better pattern. The bug in isUsedInBasicBlock was also causing other tests to test the wrong thing entirely: for example we weren't actually disabling speculation for floating point operations as intended (and tested), but the test passed because we failed to speculate them due to the isUsedInBasicBlock failure. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173417 91177308-0d34-0410-b5e6-96231b3b80d8

Reapply chandlerc's r173342 now that the miscompile it was triggering is fixed.

2013-01-24T16:44:25Z

Original commit message: Plug TTI into the speculation logic, giving it a real cost interface that can be specialized by targets. The goal here is not to be more aggressive, but to just be more accurate with very obvious cases. There are instructions which are known to be truly free and which were not being modeled as such in this code -- see the regression test which is distilled from an inner loop of zlib. Everywhere the TTI cost model is insufficiently conservative I've added explicit checks with FIXME comments to go add proper modelling of these cost factors. If this causes regressions, the likely solution is to make TTI even more conservative in its cost estimates, but test cases will help here. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173357 91177308-0d34-0410-b5e6-96231b3b80d8

Revert r173342 temporarily. It appears to cause a very late miscompile

2013-01-24T13:24:24Z

of stage2 in a bootstrap. Still investigating.... git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173343 91177308-0d34-0410-b5e6-96231b3b80d8

Plug TTI into the speculation logic, giving it a real cost interface

2013-01-24T12:39:29Z

that can be specialized by targets. The goal here is not to be more aggressive, but to just be more accurate with very obvious cases. There are instructions which are known to be truly free and which were not being modeled as such in this code -- see the regression test which is distilled from an inner loop of zlib. Everywhere the TTI cost model is insufficiently conservative I've added explicit checks with FIXME comments to go add proper modelling of these cost factors. If this causes regressions, the likely solution is to make TTI even more conservative in its cost estimates, but test cases will help here. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173342 91177308-0d34-0410-b5e6-96231b3b80d8

Address a large chunk of this FIXME by accumulating the cost for

2013-01-24T12:05:17Z

unfolded constant expressions rather than checking each one independently. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173341 91177308-0d34-0410-b5e6-96231b3b80d8