From 3eddf499b785903050e9f7e8b5bd696654503b73 Mon Sep 17 00:00:00 2001
From: Peter Collingbourne <peter@pcc.me.uk>
Date: Wed, 29 Jul 2015 18:12:36 +0000
Subject: [PATCH] LowerBitSets: Add debugging output.

Differential Revision: http://reviews.llvm.org/D11583

llvm-svn: 243546
---
 llvm/include/llvm/Transforms/IPO/LowerBitSets.h |  3 +++
 llvm/lib/Transforms/IPO/LowerBitSets.cpp        | 22 ++++++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/llvm/include/llvm/Transforms/IPO/LowerBitSets.h b/llvm/include/llvm/Transforms/IPO/LowerBitSets.h
index 55d7d84..f678e86 100644
--- a/llvm/include/llvm/Transforms/IPO/LowerBitSets.h
+++ b/llvm/include/llvm/Transforms/IPO/LowerBitSets.h
@@ -28,6 +28,7 @@ namespace llvm {
 class DataLayout;
 class GlobalVariable;
 class Value;
+class raw_ostream;
 
 struct BitSetInfo {
   // The indices of the set bits in the bitset.
@@ -57,6 +58,8 @@ struct BitSetInfo {
   bool containsValue(const DataLayout &DL,
                      const DenseMap<GlobalVariable *, uint64_t> &GlobalLayout,
                      Value *V, uint64_t COffset = 0) const;
+
+  void print(raw_ostream &OS) const;
 };
 
 struct BitSetBuilder {
diff --git a/llvm/lib/Transforms/IPO/LowerBitSets.cpp b/llvm/lib/Transforms/IPO/LowerBitSets.cpp
index c6795c6..bf386a6 100644
--- a/llvm/lib/Transforms/IPO/LowerBitSets.cpp
+++ b/llvm/lib/Transforms/IPO/LowerBitSets.cpp
@@ -26,6 +26,8 @@
 #include "llvm/IR/Module.h"
 #include "llvm/IR/Operator.h"
 #include "llvm/Pass.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
 
 using namespace llvm;
@@ -90,6 +92,22 @@ bool BitSetInfo::containsValue(
   return false;
 }
 
+void BitSetInfo::print(raw_ostream &OS) const {
+  OS << "offset " << ByteOffset << " size " << BitSize << " align "
+     << (1 << AlignLog2);
+
+  if (isAllOnes()) {
+    OS << " all-ones\n";
+    return;
+  }
+
+  OS << " { ";
+  for (uint64_t B : Bits)
+    OS << B << ' ';
+  OS << "}\n";
+  return;
+}
+
 BitSetInfo BitSetBuilder::build() {
   if (Min > Max)
     Min = 0;
@@ -532,6 +550,10 @@ void LowerBitSets::buildBitSetsFromGlobals(
   for (MDString *BS : BitSets) {
     // Build the bitset.
     BitSetInfo BSI = buildBitSet(BS, GlobalLayout);
+    DEBUG({
+      dbgs() << BS->getString() << ": ";
+      BSI.print(dbgs());
+    });
 
     ByteArrayInfo *BAI = 0;
 
-- 
2.7.4