[PATCH] [PowerPC] Add Power8 Instruction Scheduling Tablegen

[hfinkel at anl.gov]

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Comment at: lib/Target/PowerPC/PPCScheduleP8.td:359
@@ +358,3 @@
+def P8Model : SchedMachineModel {
+  let IssueWidth = 8;  // up to 8 instructions dispatched per cycle.
+                       // up to six non-branch instructions.
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If your comments capture the entire picture, then this should be 6, not 8. I think that, the real question, however, is not the instructions in each dispatch group going in, but how many (non-branch) instructions can be issued per cycle to the various pipelines.

On the P7, this is 8 (two of which are branches, so 6 regular instructions), even though we can have only 4 per dispatch group. That;s why I put 6 in this field for the P7.

http://reviews.llvm.org/D6358