From b1210c059d1ef084ecd275ed0ffb8343ac3cdfad Mon Sep 17 00:00:00 2001
From: Roman Lebedev <lebedev.ri@gmail.com>
Date: Sun, 26 Jul 2020 14:05:00 +0300
Subject: [PATCH] [NFC][XRay] Account: migrate to DenseMap + SmallVector, -16%
 faster on large (3.8G) input

DenseMap is a single allocation underneath, so this is has pretty expected
performance impact on large-ish (3.8G) xray log processing time.
---
 llvm/tools/llvm-xray/xray-account.h | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/llvm/tools/llvm-xray/xray-account.h b/llvm/tools/llvm-xray/xray-account.h
index b63ecc59b71ad..575114d6096a2 100644
--- a/llvm/tools/llvm-xray/xray-account.h
+++ b/llvm/tools/llvm-xray/xray-account.h
@@ -27,12 +27,14 @@ namespace xray {
 
 class LatencyAccountant {
 public:
-  typedef std::map<int32_t, std::vector<uint64_t>> FunctionLatencyMap;
-  typedef std::map<uint32_t, std::pair<uint64_t, uint64_t>>
+  typedef llvm::DenseMap<int32_t, llvm::SmallVector<uint64_t, 0>>
+      FunctionLatencyMap;
+  typedef llvm::DenseMap<uint32_t, std::pair<uint64_t, uint64_t>>
       PerThreadMinMaxTSCMap;
-  typedef std::map<uint8_t, std::pair<uint64_t, uint64_t>> PerCPUMinMaxTSCMap;
-  typedef std::vector<std::pair<int32_t, uint64_t>> FunctionStack;
-  typedef std::map<uint32_t, FunctionStack> PerThreadFunctionStackMap;
+  typedef llvm::DenseMap<uint8_t, std::pair<uint64_t, uint64_t>>
+      PerCPUMinMaxTSCMap;
+  typedef llvm::SmallVector<std::pair<int32_t, uint64_t>, 32> FunctionStack;
+  typedef llvm::DenseMap<uint32_t, FunctionStack> PerThreadFunctionStackMap;
 
 private:
   PerThreadFunctionStackMap PerThreadFunctionStack;