[llvm-exegesis] Add support for measuring NumMicroOps.

Summary:
Example output for vzeroall:

---
mode:            uops
key:
  instructions:
    - 'VZEROALL'
  config:          ''
  register_initial_values:
cpu_name:        haswell
llvm_triple:     x86_64-unknown-linux-gnu
num_repetitions: 10000
measurements:
  - { debug_string: HWPort0, value: 0.0006, per_snippet_value: 0.0006,
      key: '3' }
  - { debug_string: HWPort1, value: 0.0011, per_snippet_value: 0.0011,
      key: '4' }
  - { debug_string: HWPort2, value: 0.0004, per_snippet_value: 0.0004,
      key: '5' }
  - { debug_string: HWPort3, value: 0.0018, per_snippet_value: 0.0018,
      key: '6' }
  - { debug_string: HWPort4, value: 0.0002, per_snippet_value: 0.0002,
      key: '7' }
  - { debug_string: HWPort5, value: 1.0019, per_snippet_value: 1.0019,
      key: '8' }
  - { debug_string: HWPort6, value: 1.0033, per_snippet_value: 1.0033,
      key: '9' }
  - { debug_string: HWPort7, value: 0.0001, per_snippet_value: 0.0001,
      key: '10' }
  - { debug_string: NumMicroOps, value: 20.0069, per_snippet_value: 20.0069,
      key: NumMicroOps }
error:           ''
info:            ''
assembled_snippet: C5FC77C5FC77C5FC77C5FC77C5FC77C5FC77C5FC77C5FC77C5FC77C5FC77C5FC77C5FC77C5FC77C5FC77C5FC77C5FC77C3
...

Reviewers: gchatelet

Subscribers: tschuett, RKSimon, andreadb, llvm-commits

Differential Revision: https://reviews.llvm.org/D52539

llvm-svn: 343094
diff --git a/llvm/utils/TableGen/CodeGenSchedule.cpp b/llvm/utils/TableGen/CodeGenSchedule.cpp
index 545e829..625944b 100644
--- a/llvm/utils/TableGen/CodeGenSchedule.cpp
+++ b/llvm/utils/TableGen/CodeGenSchedule.cpp
@@ -1787,6 +1787,15 @@
     }
     PM.PfmCycleCounterDef = Def;
   }
+  for (Record *Def : Records.getAllDerivedDefinitions("PfmUopsCounter")) {
+    CodeGenProcModel &PM = getProcModel(Def->getValueAsDef("SchedModel"));
+    if (PM.PfmUopsCounterDef) {
+      PrintFatalError(Def->getLoc(),
+                      "multiple uops counters for " +
+                          Def->getValueAsDef("SchedModel")->getName());
+    }
+    PM.PfmUopsCounterDef = Def;
+  }
 }
 
 // Collect and sort WriteRes, ReadAdvance, and ProcResources.