From 5d67d8916e711daf4dd961d27f49ed408938be7c Mon Sep 17 00:00:00 2001
From: Sanjay Patel <spatel@rotateright.com>
Date: Thu, 24 Aug 2017 14:43:33 +0000
Subject: [PATCH] [BypassSlowDivision] move map helper code to header; NFC

We can reuse this code with other div/rem transforms as shown in:
https://reviews.llvm.org/D31037
https://bugs.llvm.org/show_bug.cgi?id=31028

llvm-svn: 311661
---
 .../Transforms/Utils/BypassSlowDivision.h     | 30 ++++++++++++++++
 .../Transforms/Utils/BypassSlowDivision.cpp   | 36 ++-----------------
 2 files changed, 32 insertions(+), 34 deletions(-)

diff --git a/llvm/include/llvm/Transforms/Utils/BypassSlowDivision.h b/llvm/include/llvm/Transforms/Utils/BypassSlowDivision.h
index af0d60b2625f..663bef2594b0 100644
--- a/llvm/include/llvm/Transforms/Utils/BypassSlowDivision.h
+++ b/llvm/include/llvm/Transforms/Utils/BypassSlowDivision.h
@@ -23,6 +23,36 @@
 
 namespace llvm {
 
+struct DivRemMapKey {
+  bool SignedOp;
+  Value *Dividend;
+  Value *Divisor;
+
+  DivRemMapKey(bool InSignedOp, Value *InDividend, Value *InDivisor)
+      : SignedOp(InSignedOp), Dividend(InDividend), Divisor(InDivisor) {}
+};
+
+template <> struct DenseMapInfo<DivRemMapKey> {
+  static bool isEqual(const DivRemMapKey &Val1, const DivRemMapKey &Val2) {
+    return Val1.SignedOp == Val2.SignedOp && Val1.Dividend == Val2.Dividend &&
+           Val1.Divisor == Val2.Divisor;
+  }
+
+  static DivRemMapKey getEmptyKey() {
+    return DivRemMapKey(false, nullptr, nullptr);
+  }
+
+  static DivRemMapKey getTombstoneKey() {
+    return DivRemMapKey(true, nullptr, nullptr);
+  }
+
+  static unsigned getHashValue(const DivRemMapKey &Val) {
+    return (unsigned)(reinterpret_cast<uintptr_t>(Val.Dividend) ^
+                      reinterpret_cast<uintptr_t>(Val.Divisor)) ^
+           (unsigned)Val.SignedOp;
+  }
+};
+
 /// This optimization identifies DIV instructions in a BB that can be
 /// profitably bypassed and carried out with a shorter, faster divide.
 ///
diff --git a/llvm/lib/Transforms/Utils/BypassSlowDivision.cpp b/llvm/lib/Transforms/Utils/BypassSlowDivision.cpp
index 83ec7f55d1af..d6c31f282e87 100644
--- a/llvm/lib/Transforms/Utils/BypassSlowDivision.cpp
+++ b/llvm/lib/Transforms/Utils/BypassSlowDivision.cpp
@@ -30,15 +30,6 @@ using namespace llvm;
 #define DEBUG_TYPE "bypass-slow-division"
 
 namespace {
-  struct DivOpInfo {
-    bool SignedOp;
-    Value *Dividend;
-    Value *Divisor;
-
-    DivOpInfo(bool InSignedOp, Value *InDividend, Value *InDivisor)
-      : SignedOp(InSignedOp), Dividend(InDividend), Divisor(InDivisor) {}
-  };
-
   struct QuotRemPair {
     Value *Quotient;
     Value *Remainder;
@@ -58,30 +49,7 @@ namespace {
 }
 
 namespace llvm {
-  template<>
-  struct DenseMapInfo<DivOpInfo> {
-    static bool isEqual(const DivOpInfo &Val1, const DivOpInfo &Val2) {
-      return Val1.SignedOp == Val2.SignedOp &&
-             Val1.Dividend == Val2.Dividend &&
-             Val1.Divisor == Val2.Divisor;
-    }
-
-    static DivOpInfo getEmptyKey() {
-      return DivOpInfo(false, nullptr, nullptr);
-    }
-
-    static DivOpInfo getTombstoneKey() {
-      return DivOpInfo(true, nullptr, nullptr);
-    }
-
-    static unsigned getHashValue(const DivOpInfo &Val) {
-      return (unsigned)(reinterpret_cast<uintptr_t>(Val.Dividend) ^
-                        reinterpret_cast<uintptr_t>(Val.Divisor)) ^
-                        (unsigned)Val.SignedOp;
-    }
-  };
-
-  typedef DenseMap<DivOpInfo, QuotRemPair> DivCacheTy;
+  typedef DenseMap<DivRemMapKey, QuotRemPair> DivCacheTy;
   typedef DenseMap<unsigned, unsigned> BypassWidthsTy;
   typedef SmallPtrSet<Instruction *, 4> VisitedSetTy;
 }
@@ -175,7 +143,7 @@ Value *FastDivInsertionTask::getReplacement(DivCacheTy &Cache) {
   // Then, look for a value in Cache.
   Value *Dividend = SlowDivOrRem->getOperand(0);
   Value *Divisor = SlowDivOrRem->getOperand(1);
-  DivOpInfo Key(isSignedOp(), Dividend, Divisor);
+  DivRemMapKey Key(isSignedOp(), Dividend, Divisor);
   auto CacheI = Cache.find(Key);
 
   if (CacheI == Cache.end()) {