[llvm] 4c3d759 - [CSSPGO] Always use callsite samples as callsite probe counts.

[Hongtao Yu via llvm-commits]

Author: Hongtao Yu
Date: 2021-03-08T22:52:36-08:00
New Revision: 4c3d759d001950dc3fa0bd721707085c295f6e20

URL: https://github.com/llvm/llvm-project/commit/4c3d759d001950dc3fa0bd721707085c295f6e20
DIFF: https://github.com/llvm/llvm-project/commit/4c3d759d001950dc3fa0bd721707085c295f6e20.diff

LOG: [CSSPGO] Always use callsite samples as callsite probe counts.

For CS profile, the callsite count of previously inlined callees is populated with the entry count of the callees. Therefore when trying to get a weight for calliste probe after inlinining, the callsite count should always be used. The same fix has already been made for non-probe case.

Reviewed By: wenlei

Differential Revision: https://reviews.llvm.org/D98094

Added: 
    

Modified: 
    llvm/lib/Transforms/IPO/SampleProfile.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/IPO/SampleProfile.cpp b/llvm/lib/Transforms/IPO/SampleProfile.cpp
index 437833148269..5ab11368d2e0 100644
--- a/llvm/lib/Transforms/IPO/SampleProfile.cpp
+++ b/llvm/lib/Transforms/IPO/SampleProfile.cpp
@@ -520,10 +520,12 @@ ErrorOr<uint64_t> SampleProfileLoader::getInstWeight(const Instruction &Inst) {
   if (isa<BranchInst>(Inst) || isa<IntrinsicInst>(Inst) || isa<PHINode>(Inst))
     return std::error_code();
 
-  // If a direct call/invoke instruction is inlined in profile
-  // (findCalleeFunctionSamples returns non-empty result), but not inlined here,
-  // it means that the inlined callsite has no sample, thus the call
-  // instruction should have 0 count.
+  // For non-CS profile, if a direct call/invoke instruction is inlined in
+  // profile (findCalleeFunctionSamples returns non-empty result), but not
+  // inlined here, it means that the inlined callsite has no sample, thus the
+  // call instruction should have 0 count.
+  // For CS profile, the callsite count of previously inlined callees is
+  // populated with the entry count of the callees.
   if (!ProfileIsCS)
     if (const auto *CB = dyn_cast<CallBase>(&Inst))
       if (!CB->isIndirectCall() && findCalleeFunctionSamples(*CB))
@@ -548,13 +550,16 @@ ErrorOr<uint64_t> SampleProfileLoader::getProbeWeight(const Instruction &Inst) {
   if (!FS)
     return std::error_code();
 
-  // If a direct call/invoke instruction is inlined in profile
-  // (findCalleeFunctionSamples returns non-empty result), but not inlined here,
-  // it means that the inlined callsite has no sample, thus the call
-  // instruction should have 0 count.
-  if (const auto *CB = dyn_cast<CallBase>(&Inst))
-    if (!CB->isIndirectCall() && findCalleeFunctionSamples(*CB))
-      return 0;
+  // For non-CS profile, If a direct call/invoke instruction is inlined in
+  // profile (findCalleeFunctionSamples returns non-empty result), but not
+  // inlined here, it means that the inlined callsite has no sample, thus the
+  // call instruction should have 0 count.
+  // For CS profile, the callsite count of previously inlined callees is
+  // populated with the entry count of the callees.
+  if (!ProfileIsCS)
+    if (const auto *CB = dyn_cast<CallBase>(&Inst))
+      if (!CB->isIndirectCall() && findCalleeFunctionSamples(*CB))
+        return 0;
 
   const ErrorOr<uint64_t> &R = FS->findSamplesAt(Probe->Id, 0);
   if (R) {