[MemProf] Merge all callee guids for indirect call VP metadata #170964
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When matching memprof profiles, for indirect calls we use the callee guids recorded on callsites in the profile to synthesize indirect call VP metadata when none exists. However, we only do this for the first matching CallSiteEntry from the profile. In some case there can be multiple, for example when the current function was eventually inlined into multiple callers. Profile generation propagates the CallSiteEntry from those callers into the inlined callee's profile as it may not yet have been inlined in the new compile. To capture all of these potential indirect call targets, merge callee guids across all matching CallSiteEntries.
Member
|
@llvm/pr-subscribers-pgo Author: Teresa Johnson (teresajohnson) ChangesWhen matching memprof profiles, for indirect calls we use the callee In some case there can be multiple, for example when the current To capture all of these potential indirect call targets, merge callee Full diff: https://github.com/llvm/llvm-project/pull/170964.diff 2 Files Affected:
diff --git a/llvm/lib/Transforms/Instrumentation/MemProfUse.cpp b/llvm/lib/Transforms/Instrumentation/MemProfUse.cpp
index 31e69784262da..011aeca9ef0f2 100644
--- a/llvm/lib/Transforms/Instrumentation/MemProfUse.cpp
+++ b/llvm/lib/Transforms/Instrumentation/MemProfUse.cpp
@@ -528,35 +528,50 @@ static void handleCallSite(
Module &M, std::set<std::vector<uint64_t>> &MatchedCallSites,
OptimizationRemarkEmitter &ORE) {
auto &Ctx = M.getContext();
+ // Set of Callee GUIDs to attach to indirect calls. We accumulate all of them
+ // to support cases where the instuction's inlined frames match multiple call
+ // site entries, which can happen if the profile was collected from a binary
+ // where this instruction was eventually inlined into multiple callers.
+ SetVector<GlobalValue::GUID> CalleeGuids;
+ bool CallsiteMDAdded = false;
for (const auto &CallSiteEntry : CallSiteEntries) {
// If we found and thus matched all frames on the call, create and
// attach call stack metadata.
if (stackFrameIncludesInlinedCallStack(CallSiteEntry.Frames,
InlinedCallStack)) {
NumOfMemProfMatchedCallSites++;
- addCallsiteMetadata(I, InlinedCallStack, Ctx);
-
- // Try to attach indirect call metadata if possible.
- if (!CalledFunction)
- addVPMetadata(M, I, CallSiteEntry.CalleeGuids);
-
// Only need to find one with a matching call stack and add a single
// callsite metadata.
-
- // Accumulate call site matching information upon request.
- if (ClPrintMemProfMatchInfo) {
- std::vector<uint64_t> CallStack;
- append_range(CallStack, InlinedCallStack);
- MatchedCallSites.insert(std::move(CallStack));
+ if (!CallsiteMDAdded) {
+ addCallsiteMetadata(I, InlinedCallStack, Ctx);
+
+ // Accumulate call site matching information upon request.
+ if (ClPrintMemProfMatchInfo) {
+ std::vector<uint64_t> CallStack;
+ append_range(CallStack, InlinedCallStack);
+ MatchedCallSites.insert(std::move(CallStack));
+ }
+ ORE.emit(OptimizationRemark(DEBUG_TYPE, "MemProfUse", &I)
+ << ore::NV("CallSite", &I) << " in function "
+ << ore::NV("Caller", I.getFunction())
+ << " matched callsite with frame count "
+ << ore::NV("Frames", InlinedCallStack.size()));
+
+ // If this is a direct call, we're done.
+ if (CalledFunction)
+ break;
+ CallsiteMDAdded = true;
}
- ORE.emit(OptimizationRemark(DEBUG_TYPE, "MemProfUse", &I)
- << ore::NV("CallSite", &I) << " in function "
- << ore::NV("Caller", I.getFunction())
- << " matched callsite with frame count "
- << ore::NV("Frames", InlinedCallStack.size()));
- break;
+
+ assert(!CalledFunction && "Didn't expect direct call");
+
+ // Collect Callee GUIDs from all matching CallSiteEntries.
+ CalleeGuids.insert(CallSiteEntry.CalleeGuids.begin(),
+ CallSiteEntry.CalleeGuids.end());
}
}
+ // Try to attach indirect call metadata if possible.
+ addVPMetadata(M, I, CalleeGuids.getArrayRef());
}
static void readMemprof(Module &M, Function &F,
diff --git a/llvm/test/Transforms/PGOProfile/memprof_annotate_indirect_call.test b/llvm/test/Transforms/PGOProfile/memprof_annotate_indirect_call.test
index ad83da285694a..54f3ed2d9e65e 100644
--- a/llvm/test/Transforms/PGOProfile/memprof_annotate_indirect_call.test
+++ b/llvm/test/Transforms/PGOProfile/memprof_annotate_indirect_call.test
@@ -18,6 +18,18 @@ HeapProfileRecords:
- Frames:
- { Function: _Z3barv, LineOffset: 3, Column: 5, IsInlineFrame: false }
CalleeGuids: [0x123456789abcdef0, 0x23456789abcdef01]
+ # The next 2 sets of frames simulates the case where this function was
+ # eventually inlined into multiple callers. We would have propagated the
+ # resulting frames and callee guids here for matching with they not yet
+ # inlined bar. We should aggregate all callee guids into the metadata.
+ - Frames:
+ - { Function: _Z3barv, LineOffset: 3, Column: 5, IsInlineFrame: true }
+ - { Function: _Z3foov, LineOffset: 1, Column: 6, IsInlineFrame: false }
+ CalleeGuids: [0x1234, 0x2345]
+ - Frames:
+ - { Function: _Z3barv, LineOffset: 3, Column: 5, IsInlineFrame: true }
+ - { Function: _Z3foov, LineOffset: 10, Column: 7, IsInlineFrame: false }
+ CalleeGuids: [0x3456, 0x4567]
...
;--- basic.ll
@@ -31,7 +43,7 @@ entry:
ret void
}
-; CHECK-ENABLE: !6 = !{!"VP", i32 0, i64 2, i64 1311768467463790320, i64 1, i64 2541551405711093505, i64 1}
+; CHECK-ENABLE: !6 = !{!"VP", i32 0, i64 6, i64 13398, i64 1, i64 17767, i64 1, i64 4660, i64 1, i64 9029, i64 1, i64 1311768467463790320, i64 1, i64 2541551405711093505, i64 1}
!llvm.module.flags = !{!2, !3}
|
Member
|
@llvm/pr-subscribers-llvm-transforms Author: Teresa Johnson (teresajohnson) ChangesWhen matching memprof profiles, for indirect calls we use the callee In some case there can be multiple, for example when the current To capture all of these potential indirect call targets, merge callee Full diff: https://github.com/llvm/llvm-project/pull/170964.diff 2 Files Affected:
diff --git a/llvm/lib/Transforms/Instrumentation/MemProfUse.cpp b/llvm/lib/Transforms/Instrumentation/MemProfUse.cpp
index 31e69784262da..011aeca9ef0f2 100644
--- a/llvm/lib/Transforms/Instrumentation/MemProfUse.cpp
+++ b/llvm/lib/Transforms/Instrumentation/MemProfUse.cpp
@@ -528,35 +528,50 @@ static void handleCallSite(
Module &M, std::set<std::vector<uint64_t>> &MatchedCallSites,
OptimizationRemarkEmitter &ORE) {
auto &Ctx = M.getContext();
+ // Set of Callee GUIDs to attach to indirect calls. We accumulate all of them
+ // to support cases where the instuction's inlined frames match multiple call
+ // site entries, which can happen if the profile was collected from a binary
+ // where this instruction was eventually inlined into multiple callers.
+ SetVector<GlobalValue::GUID> CalleeGuids;
+ bool CallsiteMDAdded = false;
for (const auto &CallSiteEntry : CallSiteEntries) {
// If we found and thus matched all frames on the call, create and
// attach call stack metadata.
if (stackFrameIncludesInlinedCallStack(CallSiteEntry.Frames,
InlinedCallStack)) {
NumOfMemProfMatchedCallSites++;
- addCallsiteMetadata(I, InlinedCallStack, Ctx);
-
- // Try to attach indirect call metadata if possible.
- if (!CalledFunction)
- addVPMetadata(M, I, CallSiteEntry.CalleeGuids);
-
// Only need to find one with a matching call stack and add a single
// callsite metadata.
-
- // Accumulate call site matching information upon request.
- if (ClPrintMemProfMatchInfo) {
- std::vector<uint64_t> CallStack;
- append_range(CallStack, InlinedCallStack);
- MatchedCallSites.insert(std::move(CallStack));
+ if (!CallsiteMDAdded) {
+ addCallsiteMetadata(I, InlinedCallStack, Ctx);
+
+ // Accumulate call site matching information upon request.
+ if (ClPrintMemProfMatchInfo) {
+ std::vector<uint64_t> CallStack;
+ append_range(CallStack, InlinedCallStack);
+ MatchedCallSites.insert(std::move(CallStack));
+ }
+ ORE.emit(OptimizationRemark(DEBUG_TYPE, "MemProfUse", &I)
+ << ore::NV("CallSite", &I) << " in function "
+ << ore::NV("Caller", I.getFunction())
+ << " matched callsite with frame count "
+ << ore::NV("Frames", InlinedCallStack.size()));
+
+ // If this is a direct call, we're done.
+ if (CalledFunction)
+ break;
+ CallsiteMDAdded = true;
}
- ORE.emit(OptimizationRemark(DEBUG_TYPE, "MemProfUse", &I)
- << ore::NV("CallSite", &I) << " in function "
- << ore::NV("Caller", I.getFunction())
- << " matched callsite with frame count "
- << ore::NV("Frames", InlinedCallStack.size()));
- break;
+
+ assert(!CalledFunction && "Didn't expect direct call");
+
+ // Collect Callee GUIDs from all matching CallSiteEntries.
+ CalleeGuids.insert(CallSiteEntry.CalleeGuids.begin(),
+ CallSiteEntry.CalleeGuids.end());
}
}
+ // Try to attach indirect call metadata if possible.
+ addVPMetadata(M, I, CalleeGuids.getArrayRef());
}
static void readMemprof(Module &M, Function &F,
diff --git a/llvm/test/Transforms/PGOProfile/memprof_annotate_indirect_call.test b/llvm/test/Transforms/PGOProfile/memprof_annotate_indirect_call.test
index ad83da285694a..54f3ed2d9e65e 100644
--- a/llvm/test/Transforms/PGOProfile/memprof_annotate_indirect_call.test
+++ b/llvm/test/Transforms/PGOProfile/memprof_annotate_indirect_call.test
@@ -18,6 +18,18 @@ HeapProfileRecords:
- Frames:
- { Function: _Z3barv, LineOffset: 3, Column: 5, IsInlineFrame: false }
CalleeGuids: [0x123456789abcdef0, 0x23456789abcdef01]
+ # The next 2 sets of frames simulates the case where this function was
+ # eventually inlined into multiple callers. We would have propagated the
+ # resulting frames and callee guids here for matching with they not yet
+ # inlined bar. We should aggregate all callee guids into the metadata.
+ - Frames:
+ - { Function: _Z3barv, LineOffset: 3, Column: 5, IsInlineFrame: true }
+ - { Function: _Z3foov, LineOffset: 1, Column: 6, IsInlineFrame: false }
+ CalleeGuids: [0x1234, 0x2345]
+ - Frames:
+ - { Function: _Z3barv, LineOffset: 3, Column: 5, IsInlineFrame: true }
+ - { Function: _Z3foov, LineOffset: 10, Column: 7, IsInlineFrame: false }
+ CalleeGuids: [0x3456, 0x4567]
...
;--- basic.ll
@@ -31,7 +43,7 @@ entry:
ret void
}
-; CHECK-ENABLE: !6 = !{!"VP", i32 0, i64 2, i64 1311768467463790320, i64 1, i64 2541551405711093505, i64 1}
+; CHECK-ENABLE: !6 = !{!"VP", i32 0, i64 6, i64 13398, i64 1, i64 17767, i64 1, i64 4660, i64 1, i64 9029, i64 1, i64 1311768467463790320, i64 1, i64 2541551405711093505, i64 1}
!llvm.module.flags = !{!2, !3}
|
passed using a std::unordered set, which defeated the MapVector's attempt at deterministic ordering. Change the unordered_set to a vector. In theory there should not be duplicated sets of call site frames within a function's profile, but even if there are, there's no harm as we only create callsite metadata for the first, and we want to include all callee guids anyway.
Collaborator
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LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/123/builds/31873 Here is the relevant piece of the build log for the reference |
honeygoyal
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Dec 9, 2025
…170964) When matching memprof profiles, for indirect calls we use the callee guids recorded on callsites in the profile to synthesize indirect call VP metadata when none exists. However, we only do this for the first matching CallSiteEntry from the profile. In some case there can be multiple, for example when the current function was eventually inlined into multiple callers. Profile generation propagates the CallSiteEntry from those callers into the inlined callee's profile as it may not yet have been inlined in the new compile. To capture all of these potential indirect call targets, merge callee guids across all matching CallSiteEntries.
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When matching memprof profiles, for indirect calls we use the callee
guids recorded on callsites in the profile to synthesize indirect call
VP metadata when none exists. However, we only do this for the first
matching CallSiteEntry from the profile.
In some case there can be multiple, for example when the current
function was eventually inlined into multiple callers. Profile
generation propagates the CallSiteEntry from those callers into the
inlined callee's profile as it may not yet have been inlined in the
new compile.
To capture all of these potential indirect call targets, merge callee
guids across all matching CallSiteEntries.