[llvm] [MemProf] Support cloning for indirect calls with ThinLTO (PR #110625)

[Snehasish Kumar via llvm-commits]

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@@ -4075,24 +4367,80 @@ bool MemProfContextDisambiguation::applyImport(Module &M) {
                      << ore::NV("Attribute", AllocTypeString));
           }
         } else if (!CallsiteContext.empty()) {
-          // Consult the next callsite node.
-          assert(SI != FS->callsites().end());
-          auto &StackNode = *(SI++);
-
+          if (!CalledFunction) {
+            // This is an indirect call, see if we have profile information and
+            // whether any clones were recorded for the profiled targets (that
+            // we synthesized CallsiteInfo summary records for when building the
+            // index).
 #ifndef NDEBUG
-          // Sanity check that the stack ids match between the summary and
-          // instruction metadata.
-          auto StackIdIndexIter = StackNode.StackIdIndices.begin();
-          for (auto StackId : CallsiteContext) {
-            assert(StackIdIndexIter != StackNode.StackIdIndices.end());
-            assert(ImportSummary->getStackIdAtIndex(*StackIdIndexIter) ==
-                   StackId);
-            StackIdIndexIter++;
+            // We should have skipped inline assembly calls.
+            auto *CI = dyn_cast<CallInst>(CB);
+            assert(!CI || !CI->isInlineAsm());
+#endif
+            // We should have skipped direct calls via a Constant.
+            assert(CalledValue && !isa<Constant>(CalledValue));
+
+            uint32_t NumCandidates;
+            uint64_t TotalCount;
+            auto CandidateProfileData =
+                ICallAnalysis.getPromotionCandidatesForInstruction(
+                    CB, TotalCount, NumCandidates);
+            if (!CandidateProfileData.empty()) {
+              unsigned CallsiteInfoStartStartIndex =
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snehasish wrote:

Should this be size_t? Also maybe use std::distance and drop the static_cast?

https://github.com/llvm/llvm-project/pull/110625