[llvm] [BOLT] Sort TakenBranches immediately before use. NFCI (PR #83333)

[Maksim Panchenko via llvm-commits]

https://github.com/maksfb created https://github.com/llvm/llvm-project/pull/83333

Move code that sorts TakenBranches right before the branches are used. We can populate TakenBranches in pre-CFG post-processing and hence have to postpone the sorting to a later point in the processing pipeline. Will add such a pass later. For now it's NFC.

>From 6197986122a9d00806226e27603d71027d5e0176 Mon Sep 17 00:00:00 2001
From: Maksim Panchenko <maks at fb.com>
Date: Tue, 12 Dec 2023 17:45:17 -0800
Subject: [PATCH] [BOLT] Sort TakenBranches immediately before use. NFCI

Move code that sorts TakenBranches right before the branches are used.
We can populate TakenBranches in pre-CFG post-processing and hence have to
postpone the sorting to a later point in the processing pipeline. Will
add such a pass later. For now it's NFC.
---
 bolt/lib/Core/BinaryFunction.cpp | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/bolt/lib/Core/BinaryFunction.cpp b/bolt/lib/Core/BinaryFunction.cpp
index 00df42c11e2239..957a9c2f72e41d 100644
--- a/bolt/lib/Core/BinaryFunction.cpp
+++ b/bolt/lib/Core/BinaryFunction.cpp
@@ -1759,13 +1759,6 @@ void BinaryFunction::postProcessJumpTables() {
       }
     }
   }
-
-  // Remove duplicates branches. We can get a bunch of them from jump tables.
-  // Without doing jump table value profiling we don't have use for extra
-  // (duplicate) branches.
-  llvm::sort(TakenBranches);
-  auto NewEnd = std::unique(TakenBranches.begin(), TakenBranches.end());
-  TakenBranches.erase(NewEnd, TakenBranches.end());
 }
 
 bool BinaryFunction::validateExternallyReferencedOffsets() {
@@ -2128,6 +2121,13 @@ Error BinaryFunction::buildCFG(MCPlusBuilder::AllocatorIdTy AllocatorId) {
   // e.g. exit(3), etc. Otherwise we'll see a false fall-through
   // blocks.
 
+  // Remove duplicates branches. We can get a bunch of them from jump tables.
+  // Without doing jump table value profiling we don't have a use for extra
+  // (duplicate) branches.
+  llvm::sort(TakenBranches);
+  auto NewEnd = std::unique(TakenBranches.begin(), TakenBranches.end());
+  TakenBranches.erase(NewEnd, TakenBranches.end());
+
   for (std::pair<uint32_t, uint32_t> &Branch : TakenBranches) {
     LLVM_DEBUG(dbgs() << "registering branch [0x"
                       << Twine::utohexstr(Branch.first) << "] -> [0x"