Merge branch 'main' into lwg-3990-clang

Author: frederick-vs-ja

.ci/metrics/metrics.py

@@ -3,6 +3,7 @@
 import os
 from dataclasses import dataclass
 import sys
+import logging
 
 import github
 from github import Github
@@ -192,6 +193,10 @@ def get_per_workflow_metrics(
             # in nanoseconds.
             created_at_ns = int(created_at.timestamp()) * 10**9
 
+            logging.info(
+                f"Adding a job metric for job {workflow_job.id} in workflow {workflow_run.id}"
+            )
+
             workflow_metrics.append(
                 JobMetrics(
                     workflow_run.name + "-" + workflow_job.name,
@@ -220,7 +225,7 @@ def upload_metrics(workflow_metrics, metrics_userid, api_key):
     """
 
     if len(workflow_metrics) == 0:
-        print("No metrics found to upload.", file=sys.stderr)
+        logging.info("No metrics found to upload.")
         return
 
     metrics_batch = []
@@ -249,9 +254,7 @@ def upload_metrics(workflow_metrics, metrics_userid, api_key):
     )
 
     if response.status_code < 200 or response.status_code >= 300:
-        print(
-            f"Failed to submit data to Grafana: {response.status_code}", file=sys.stderr
-        )
+        logging.info(f"Failed to submit data to Grafana: {response.status_code}")
 
 
 def main():
@@ -275,7 +278,7 @@ def main():
         current_metrics += get_sampled_workflow_metrics(github_repo)
 
         upload_metrics(current_metrics, grafana_metrics_userid, grafana_api_key)
-        print(f"Uploaded {len(current_metrics)} metrics", file=sys.stderr)
+        logging.info(f"Uploaded {len(current_metrics)} metrics")
 
         for workflow_metric in reversed(current_metrics):
             if isinstance(workflow_metric, JobMetrics):
@@ -287,4 +290,5 @@ def main():
 
 
 if __name__ == "__main__":
+    logging.basicConfig(level=logging.INFO)
     main()

.github/workflows/libcxx-build-and-test.yaml

@@ -255,11 +255,11 @@ jobs:
       - name: Install a current LLVM
         if: ${{ matrix.mingw != true }}
         run: |
-          choco install -y llvm --version=18.1.6 --allow-downgrade
+          choco install -y llvm --version=19.1.7 --allow-downgrade
       - name: Install llvm-mingw
         if: ${{ matrix.mingw == true }}
         run: |
-          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/20240606/llvm-mingw-20240606-ucrt-x86_64.zip
+          curl -LO https://github.com/mstorsjo/llvm-mingw/releases/download/20250114/llvm-mingw-20250114-ucrt-x86_64.zip
           powershell Expand-Archive llvm-mingw*.zip -DestinationPath .
           del llvm-mingw*.zip
           mv llvm-mingw* c:\llvm-mingw

bolt/include/bolt/Passes/ContinuityStats.h

@@ -0,0 +1,98 @@
+//===- bolt/Passes/ProfileQualityStats.h ------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass checks the BOLT input profile quality.
+//
+// Check 1: how well the input profile satisfies the following
+// "CFG continuity" property of a perfect profile:
+//
+//        Each positive-execution-count block in the function’s CFG
+//        is *reachable* from a positive-execution-count function
+//        entry block through a positive-execution-count path.
+//
+// More specifically, for each of the hottest 1000 functions, the pass
+// calculates the function’s fraction of basic block execution counts
+// that is *unreachable*. It then reports the 95th percentile of the
+// distribution of the 1000 unreachable fractions in a single BOLT-INFO line.
+// The smaller the reported value is, the better the BOLT profile
+// satisfies the CFG continuity property.
+//
+// Check 2: how well the input profile satisfies the "call graph flow
+// conservation" property of a perfect profile:
+//
+//        For each function that is not a program entry, the number of times the
+//        function is called is equal to the net CFG outflow of the
+//        function's entry block(s).
+//
+// More specifically, for each of the hottest 1000 functions, the pass obtains
+// A = number of times the function is called, B = the function's entry blocks'
+// inflow, C = the function's entry blocks' outflow, where B and C are computed
+// using the function's weighted CFG. It then computes gap = 1 - MIN(A,C-B) /
+// MAX(A, C-B). The pass reports the 95th percentile of the distribution of the
+// 1000 gaps in a single BOLT-INFO line. The smaller the reported value is, the
+// better the BOLT profile satisfies the call graph flow conservation property.
+//
+// Check 3: how well the input profile satisfies the "function CFG flow
+// conservation property" of a perfect profile:
+//
+//       A non-entry non-exit basic block's inflow is equal to its outflow.
+//
+// More specifically, for each of the hottest 1000 functions, the pass loops
+// over its basic blocks that are non-entry and non-exit, and for each block
+// obtains a block gap = 1 - MIN(block inflow, block outflow, block call count
+// if any) / MAX(block inflow, block outflow, block call count if any). It then
+// aggregates the block gaps into 2 values for the function: "weighted" is the
+// weighted average of the block conservation gaps, where the weights depend on
+// each block's execution count and instruction count; "worst" is the worst
+// (biggest) block gap acorss all basic blocks in the function with an execution
+// count of > 500. The pass then reports the 95th percentile of the weighted and
+// worst values of the 1000 functions in a single BOLT-INFO line. The smaller
+// the reported values are, the better the BOLT profile satisfies the function
+// CFG flow conservation property.
+//
+// The default value of 1000 above can be changed via the hidden BOLT option
+// `-top-functions-for-profile-quality-check=[N]`.
+// The default reporting of the 95th percentile can be changed via the hidden
+// BOLT option `-percentile-for-profile-quality-check=[M]`.
+//
+// If more detailed stats are needed, `-v=1` can be used: the hottest N
+// functions will be grouped into 5 equally-sized buckets, from the hottest
+// to the coldest; for each bucket, various summary statistics of the
+// profile quality will be reported.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef BOLT_PASSES_PROFILEQUALITYSTATS_H
+#define BOLT_PASSES_PROFILEQUALITYSTATS_H
+
+#include "bolt/Passes/BinaryPasses.h"
+#include <vector>
+
+namespace llvm {
+
+class raw_ostream;
+
+namespace bolt {
+class BinaryContext;
+
+/// Compute and report to the user the profile quality
+class PrintProfileQualityStats : public BinaryFunctionPass {
+public:
+  explicit PrintProfileQualityStats(const cl::opt<bool> &PrintPass)
+      : BinaryFunctionPass(PrintPass) {}
+
+  bool shouldOptimize(const BinaryFunction &BF) const override;
+  const char *getName() const override { return "profile-quality-stats"; }
+  bool shouldPrint(const BinaryFunction &) const override { return false; }
+  Error runOnFunctions(BinaryContext &BC) override;
+};
+
+} // namespace bolt
+} // namespace llvm
+
+#endif // BOLT_PASSES_PROFILEQUALITYSTATS_H

bolt/include/bolt/Passes/ProfileQualityStats.h

@@ -505,6 +505,9 @@ class RewriteInstance {
   /// Number of local symbols in newly written symbol table.
   uint64_t NumLocalSymbols{0};
 
+  /// Flag indicating runtime library linking just started.
+  bool StartLinkingRuntimeLib{false};
+
   /// Information on special Procedure Linkage Table sections. There are
   /// multiple variants generated by different linkers.
   struct PLTSectionInfo {

bolt/include/bolt/Rewrite/RewriteInstance.h

@@ -1544,15 +1544,11 @@ MCSymbol *BinaryFunction::registerBranch(uint64_t Src, uint64_t Dst) {
 }
 
 void BinaryFunction::analyzeInstructionForFuncReference(const MCInst &Inst) {
-  for (const MCOperand &Op : MCPlus::primeOperands(Inst)) {
-    if (!Op.isExpr())
+  for (unsigned OpNum = 0; OpNum < MCPlus::getNumPrimeOperands(Inst); ++OpNum) {
+    const MCSymbol *Symbol = BC.MIB->getTargetSymbol(Inst, OpNum);
+    if (!Symbol)
       continue;
-    const MCExpr &Expr = *Op.getExpr();
-    if (Expr.getKind() != MCExpr::SymbolRef)
-      continue;
-    const MCSymbol &Symbol = cast<MCSymbolRefExpr>(Expr).getSymbol();
-    // Set HasAddressTaken for a function regardless of the ICF level.
-    if (BinaryFunction *BF = BC.getFunctionForSymbol(&Symbol))
+    if (BinaryFunction *BF = BC.getFunctionForSymbol(Symbol))
       BF->setHasAddressTaken(true);
   }
 }

bolt/lib/Core/BinaryFunction.cpp

@@ -27,7 +27,7 @@ add_llvm_library(LLVMBOLTPasses
   PatchEntries.cpp
   PettisAndHansen.cpp
   PLTCall.cpp
-  ContinuityStats.cpp
+  ProfileQualityStats.cpp
   RegAnalysis.cpp
   RegReAssign.cpp
   ReorderAlgorithm.cpp