[llvm] [NFC][DecoderEmitter] Arrange functions by class 1/N (PR #157107)

[Rahul Joshi via llvm-commits]

https://github.com/jurahul created https://github.com/llvm/llvm-project/pull/157107

None

>From 162a6ecf2ddccea3eee1377cf3e606162b4dc759 Mon Sep 17 00:00:00 2001
From: Rahul Joshi <rjoshi at nvidia.com>
Date: Fri, 5 Sep 2025 06:28:35 -0700
Subject: [PATCH] [NFC][DecoderEmitter] Move some Filter/FilterChooser members

---
 llvm/utils/TableGen/DecoderEmitter.cpp | 52 +++++++++++---------------
 1 file changed, 21 insertions(+), 31 deletions(-)

diff --git a/llvm/utils/TableGen/DecoderEmitter.cpp b/llvm/utils/TableGen/DecoderEmitter.cpp
index ebb7deb757c44..1fb8032716c7b 100644
--- a/llvm/utils/TableGen/DecoderEmitter.cpp
+++ b/llvm/utils/TableGen/DecoderEmitter.cpp
@@ -407,10 +407,6 @@ class DecoderEmitter {
   void parseInstructionEncodings();
 };
 
-} // end anonymous namespace
-
-namespace {
-
 /// Filter - Filter works with FilterChooser to produce the decoding tree for
 /// the ISA.
 ///
@@ -665,11 +661,8 @@ class DecoderTableBuilder {
 
 } // end anonymous namespace
 
-///////////////////////////
-//                       //
-// Filter Implementation //
-//                       //
-///////////////////////////
+//------------------------------------------------------------------------------
+// Filter Implementation
 
 Filter::Filter(ArrayRef<InstructionEncoding> Encodings,
                ArrayRef<unsigned> EncodingIDs, unsigned StartBit,
@@ -697,6 +690,15 @@ Filter::Filter(ArrayRef<InstructionEncoding> Encodings,
          "Filter returns no instruction categories");
 }
 
+// Returns the number of fanout produced by the filter.  More fanout implies
+// the filter distinguishes more categories of instructions.
+unsigned Filter::usefulness() const {
+  return FilteredIDs.size() + VariableIDs.empty();
+}
+
+//------------------------------------------------------------------------------
+// FilterChooser Implementation
+
 void FilterChooser::applyFilter(const Filter &F) {
   StartBit = F.StartBit;
   NumBits = F.NumBits;
@@ -724,18 +726,18 @@ void FilterChooser::applyFilter(const Filter &F) {
   }
 }
 
-// Returns the number of fanout produced by the filter.  More fanout implies
-// the filter distinguishes more categories of instructions.
-unsigned Filter::usefulness() const {
-  return FilteredIDs.size() + VariableIDs.empty();
+/// dumpStack - dumpStack traverses the filter chooser chain and calls
+/// dumpFilterArray on each filter chooser up to the top level one.
+void FilterChooser::dumpStack(raw_ostream &OS, indent Indent,
+                              unsigned PadToWidth) const {
+  if (Parent)
+    Parent->dumpStack(OS, Indent, PadToWidth);
+  assert(PadToWidth >= FilterBits.getBitWidth());
+  OS << Indent << indent(PadToWidth - FilterBits.getBitWidth());
+  printKnownBits(OS, FilterBits, '.');
+  OS << '\n';
 }
 
-//////////////////////////////////
-//                              //
-// Filterchooser Implementation //
-//                              //
-//////////////////////////////////
-
 // Emit the decoder state machine table. Returns a mask of MCD decoder ops
 // that were emitted.
 unsigned DecoderEmitter::emitTable(formatted_raw_ostream &OS,
@@ -1057,18 +1059,6 @@ void DecoderEmitter::emitDecoderFunction(formatted_raw_ostream &OS,
   OS << "}\n";
 }
 
-/// dumpStack - dumpStack traverses the filter chooser chain and calls
-/// dumpFilterArray on each filter chooser up to the top level one.
-void FilterChooser::dumpStack(raw_ostream &OS, indent Indent,
-                              unsigned PadToWidth) const {
-  if (Parent)
-    Parent->dumpStack(OS, Indent, PadToWidth);
-  assert(PadToWidth >= FilterBits.getBitWidth());
-  OS << Indent << indent(PadToWidth - FilterBits.getBitWidth());
-  printKnownBits(OS, FilterBits, '.');
-  OS << '\n';
-}
-
 // Calculates the island(s) needed to decode the instruction.
 // This returns a list of undecoded bits of an instructions, for example,
 // Inst{20} = 1 && Inst{3-0} == 0b1111 represents two islands of yet-to-be