Emit less compiler optimization remarks in samplepgo to reduce a call to findCalleeFunctionSamples which is going to be refactored.

[danielcdh]

Summary

Now the SamplePGO support is more stable, we do not need so many verbose optimization remarks emitted.

[davidxl]

looks good. The raw # of samples does not mean anything to users.

lib/Transforms/IPO/SampleProfile.cpp

for (auto I : CIS) {
       }
       if (!CalledFunction || !CalledFunction->getSubprogram()) {
         findCalleeFunctionSamples(*I)->findImportedFunctions(
             ImportGUIDs, F.getParent(),
             Samples->getTotalSamples() * SampleProfileHotThreshold / 100);
         continue;
       }
       DebugLoc DLoc = I->getDebugLoc();
-      uint64_t NumSamples = findCalleeFunctionSamples(*I)->getTotalSamples();
       if (InlineFunction(CallSite(DI), IFI)) {
         LocalChanged = true;
         emitOptimizationRemark(Ctx, DEBUG_TYPE, F, DLoc,
                                Twine("inlined hot callee '") +
-                                   CalledFunction->getName() + "' with " +
-                                   Twine(NumSamples) + " samples into '" +
+                                   CalledFunction->getName() + "' into '" +
                                    F.getName() + "'");
       }
     }
     if (LocalChanged) {
       Changed = true;
     } else {
       break;
     }

test/Transforms/SampleProfile/inline-coverage.ll

 ;     6
 ;     7    int main() {
 ;     8      long long int sum = 0;
 ;     9      for (int i = 0; i < 200000 * 3000; i++)
 ;    10        sum += foo(i);
 ;    11      return sum > 0 ? 0 : 1;
 ;    12    }
 ;
-; CHECK: remark: coverage.cc:10:12: inlined hot callee '_Z3fool' with 172746 samples into 'main'
+; CHECK: remark: coverage.cc:10:12: inlined hot callee '_Z3fool' into 'main'
 ; CHECK: remark: coverage.cc:9:21: Applied 23478 samples from profile (offset: 2.1)
 ; CHECK: remark: coverage.cc:10:16: Applied 23478 samples from profile (offset: 3)
 ; CHECK: remark: coverage.cc:4:10: Applied 31878 samples from profile (offset: 1)
 ; CHECK: remark: coverage.cc:11:10: Applied 0 samples from profile (offset: 4)
 ; CHECK: remark: coverage.cc:10:16: most popular destination for conditional branches at coverage.cc:9:3
 ;
 ; There is one sample record with 0 samples at offset 4 in main() that we never
 ; use:

test/Transforms/SampleProfile/remarks.ll

 ;     9          sum += -i * rand();
 ;    10      return sum;
 ;    11    }
 ;    12
 ;    13    int main() { return foo() > 0; }
 
 ; We are expecting foo() to be inlined in main() (almost all the cycles are
 ; spent inside foo).
-; CHECK: remark: remarks.cc:13:21: inlined hot callee '_Z3foov' with 623868 samples into 'main'
+; CHECK: remark: remarks.cc:13:21: inlined hot callee '_Z3foov' into 'main'
 
 ; The back edge for the loop is the hottest edge in the loop subgraph.
 ; CHECK: remark: remarks.cc:6:9: most popular destination for conditional branches at remarks.cc:5:3
 
 ; The predicate almost always chooses the 'else' branch.
 ; CHECK: remark: remarks.cc:9:15: most popular destination for conditional branches at remarks.cc:6:9
 
 ; Function Attrs: nounwind uwtable