Commit Graph

9 Commits

Author SHA1 Message Date
Benjamin Kramer
00e08fcaa0 Canonicalize header guards into a common format.
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)

Changes made by clang-tidy with minor tweaks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215558 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-13 16:26:38 +00:00
Gerolf Hoflehner
b0b708854e MachineCombiner Pass for selecting faster instruction
sequence -  target independent framework

 When the DAGcombiner selects instruction sequences
 it could increase the critical path or resource len.

 For example, on arm64 there are multiply-accumulate instructions (madd,
 msub). If e.g. the equivalent  multiply-add sequence is not on the
 crictial path it makes sense to select it instead of  the combined,
 single accumulate instruction (madd/msub). The reason is that the
 conversion from add+mul to the madd could lengthen the critical path
 by the latency of the multiply.

 But the DAGCombiner would always combine and select the madd/msub
 instruction.

 This patch uses machine trace metrics to estimate critical path length
 and resource length of an original instruction sequence vs a combined
 instruction sequence and picks the faster code based on its estimates.

 This patch only commits the target independent framework that evaluates
 and selects code sequences. The machine instruction combiner is turned
 off for all targets and expected to evolve over time by gradually
 handling DAGCombiner pattern in the target specific code.

 This framework lays the groundwork for fixing
 rdar://16319955



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214666 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-03 21:35:39 +00:00
Craig Topper
4ba844388c [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206142 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-14 00:51:57 +00:00
Craig Topper
9f998de891 [C++11] Add 'override' keyword to virtual methods that override their base class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203220 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-07 09:26:03 +00:00
Dmitri Gribenko
5c332dbd30 Add ArrayRef constructor from None, and do the cleanups that this constructor enables
Patch by Robert Wilhelm.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181138 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-05 00:40:33 +00:00
Andrew Trick
3aa5394e5b Generalize the MachineTraceMetrics public API.
Naturally, we should be able to pass in extra instructions, not just
extra blocks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180667 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-27 03:54:20 +00:00
Jakob Stoklund Olesen
8396e13042 Count processor resources individually in MachineTraceMetrics.
The new instruction scheduling models provide information about the
number of cycles consumed on each processor resource. This makes it
possible to estimate ILP more accurately than simply counting
instructions / issue width.

The functions getResourceDepth() and getResourceLength() now identify
the limiting processor resource, and return a cycle count based on that.

This gives more precise resource information, particularly in traces
that use one resource a lot more than others.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178553 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-02 17:49:51 +00:00
Jakob Stoklund Olesen
6ffcd5efe1 Rename isEarlierInSameTrace to isUsefulDominator.
In very rare cases caused by irreducible control flow, the dominating
block can have the same trace head without actually being part of the
trace.

As long as such a dominator still has valid instruction depths, it is OK
to use it for computing instruction depths.

Rename the function to avoid lying, and add a check that instruction
depths are computed for the dominator.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176668 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-07 23:55:49 +00:00
Jakob Stoklund Olesen
5ed625c3cf Move MachineTraceMetrics.h into include/llvm/CodeGen.
Let targets use it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172688 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-17 01:06:04 +00:00