[LSR] Tweak debug output to always print initial cost

Author: preames

llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp

@@ -5251,8 +5251,6 @@ void LSRInstance::Solve(SmallVectorImpl<const Formula *> &Solution) const {
   assert(Solution.size() == Uses.size() && "Malformed solution!");
 
   if (BaselineCost.isLess(SolutionCost)) {
-    LLVM_DEBUG(dbgs() << "The baseline solution requires ";
-               BaselineCost.print(dbgs()); dbgs() << "\n");
     if (!AllowDropSolutionIfLessProfitable)
       LLVM_DEBUG(
           dbgs() << "Baseline is more profitable than chosen solution, "
@@ -5931,6 +5929,8 @@ LSRInstance::LSRInstance(Loop *L, IVUsers &IU, ScalarEvolution &SE,
 
   LLVM_DEBUG(dbgs() << "LSR found " << Uses.size() << " uses:\n";
              print_uses(dbgs()));
+  LLVM_DEBUG(dbgs() << "The baseline solution requires ";
+             BaselineCost.print(dbgs()); dbgs() << "\n");
 
   // Now use the reuse data to generate a bunch of interesting ways
   // to formulate the values needed for the uses.

llvm/test/Transforms/LoopStrengthReduce/RISCV/lsr-drop-solution-dbg-msg.ll

@@ -6,8 +6,8 @@ target datalayout = "e-m:e-p:64:64-i64:64-i128:128-n64-S128"
 target triple = "riscv64-unknown-linux-gnu"
 
 define ptr @foo(ptr %a0, ptr %a1, i64 %a2) {
-;DEBUG: The chosen solution requires 3 instructions 6 regs, with addrec cost 1, plus 2 base adds, plus 5 setup cost
 ;DEBUG: The baseline solution requires 2 instructions 4 regs, with addrec cost 2, plus 3 setup cost
+;DEBUG: The chosen solution requires 3 instructions 6 regs, with addrec cost 1, plus 2 base adds, plus 5 setup cost
 ;DEBUG: Baseline is more profitable than chosen solution, dropping LSR solution.
 
 ;DEBUG2: Baseline is more profitable than chosen solution, add option 'lsr-drop-solution' to drop LSR solution.