From 6f73588fb9d1d9f555abd9ef3b44e92ff2d2a1b1 Mon Sep 17 00:00:00 2001
From: Davide Italiano <davide@freebsd.org>
Date: Thu, 14 Jul 2016 20:25:54 +0000
Subject: [PATCH] [SCCP] Pass the Solver by reference, copies are expensive ...

.. enough to cause LTO compile time to regress insanely.
Thanks *a lot* to Rafael for reporting the problem and testing
the fix!

llvm-svn: 275468
---
 llvm/lib/Transforms/Scalar/SCCP.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/Transforms/Scalar/SCCP.cpp b/llvm/lib/Transforms/Scalar/SCCP.cpp
index 6ef7a20..d7a541d 100644
--- a/llvm/lib/Transforms/Scalar/SCCP.cpp
+++ b/llvm/lib/Transforms/Scalar/SCCP.cpp
@@ -1510,7 +1510,7 @@ bool SCCPSolver::ResolvedUndefsIn(Function &F) {
   return false;
 }
 
-static bool tryToReplaceWithConstant(SCCPSolver Solver, Value *V) {
+static bool tryToReplaceWithConstant(SCCPSolver &Solver, Value *V) {
   Constant *Const = nullptr;
   if (V->getType()->isStructTy()) {
     std::vector<LatticeVal> IVs = Solver.getStructLatticeValueFor(V);
@@ -1540,7 +1540,7 @@ static bool tryToReplaceWithConstant(SCCPSolver Solver, Value *V) {
   return true;
 }
 
-static bool tryToReplaceInstWithConstant(SCCPSolver Solver, Instruction *Inst,
+static bool tryToReplaceInstWithConstant(SCCPSolver &Solver, Instruction *Inst,
                                          bool shouldEraseFromParent) {
   if (!tryToReplaceWithConstant(Solver, Inst))
     return false;
-- 
2.7.4