Update test for enabling ICP for AutoFDO.

[danielcdh]

Summary

This is the test update patch for https://reviews.llvm.org/D34662

[danielcdh]

update comments

[davidxl]

test/CodeGen/pgo-sample-thinlto-summary.c

39

Is the thinLTO behavior here expected?

[danielcdh]

test/CodeGen/pgo-sample-thinlto-summary.c

39

Yes, it's expected, icp is turned off for the samplepgo thinlto summary phase (details in https://reviews.llvm.org/D31217)

[davidxl]

lgtm

test/CodeGen/pgo-sample-thinlto-summary.c

 // O2: call{{.*}}baz
 // THINLTO: call{{.*}}baz
 // THINLTO-NOT: call{{.*}}baz
 void unroll() {
   for (int i = 0; i < 2; i++)
     baz(i);
 }
 
-// Check that icp is not invoked (both -O2 and ThinLTO).
+// Check that icp is not invoked for ThinLTO, but invoked for -O2.
 // O2-LABEL: define void @icp
 // THINLTO-LABEL: define void @icp
-// O2-NOT: if.true.direct_targ
+// O2: if.true.direct_targ
 // ThinLTO-NOT: if.true.direct_targ
 void icp(void (*p)()) {
   p();
 }