Index: include/llvm/ADT/APFloat.h
===================================================================
--- include/llvm/ADT/APFloat.h
+++ include/llvm/ADT/APFloat.h
@@ -1119,6 +1119,21 @@
     llvm_unreachable("Unexpected semantics");
   }
 
+  /// We don't rely on operator== working on double values, as
+  /// it returns true for things that are clearly not equal, like -0.0 and 0.0.
+  /// As such, this method can be used to do an exact bit-for-bit comparison of
+  /// two floating point values.
+  ///
+  /// We leave the version with the double argument here because it's just so
+  /// convenient to write "2.0" and the like.  Without this function we'd
+  /// have to duplicate its logic everywhere it's called.
+  bool isExactlyValue(double V) const {
+    bool ignored;
+    APFloat Tmp(V);
+    Tmp.convert(getSemantics(), APFloat::rmNearestTiesToEven, &ignored);
+    return bitwiseIsEqual(Tmp);
+  }
+
   unsigned int convertToHexString(char *DST, unsigned int HexDigits,
                                   bool UpperCase, roundingMode RM) const {
     APFLOAT_DISPATCH_ON_SEMANTICS(
Index: include/llvm/CodeGen/SelectionDAGNodes.h
===================================================================
--- include/llvm/CodeGen/SelectionDAGNodes.h
+++ include/llvm/CodeGen/SelectionDAGNodes.h
@@ -1490,11 +1490,7 @@
   /// convenient to write "2.0" and the like.  Without this function we'd
   /// have to duplicate its logic everywhere it's called.
   bool isExactlyValue(double V) const {
-    bool ignored;
-    APFloat Tmp(V);
-    Tmp.convert(Value->getValueAPF().getSemantics(),
-                APFloat::rmNearestTiesToEven, &ignored);
-    return isExactlyValue(Tmp);
+    return Value->getValueAPF().isExactlyValue(V);
   }
   bool isExactlyValue(const APFloat& V) const;
 
Index: include/llvm/Target/TargetSelectionDAG.td
===================================================================
--- include/llvm/Target/TargetSelectionDAG.td
+++ include/llvm/Target/TargetSelectionDAG.td
@@ -676,12 +676,41 @@
 // If FastIsel should ignore all instructions that have an operand of this type,
 // the FastIselShouldIgnore flag can be set.  This is an optimization to reduce
 // the code size of the generated fast instruction selector.
-class ImmLeaf<ValueType vt, code pred, SDNodeXForm xform = NOOP_SDNodeXForm>
-  : PatFrag<(ops), (vt imm), [{}], xform> {
+class ImmLeaf<ValueType vt, code pred, SDNodeXForm xform = NOOP_SDNodeXForm,
+              SDNode ImmNode = imm>
+  : PatFrag<(ops), (vt ImmNode), [{}], xform> {
   let ImmediateCode = pred;
   bit FastIselShouldIgnore = 0;
+
+  // Is the data type of the immediate an APInt?
+  bit IsAPInt = 0;
+
+  // Is the data type of the immediate an APFloat?
+  bit IsAPFloat = 0;
 }
 
+// An ImmLeaf except that Imm is an APInt. This is useful when you need to
+// zero-extend the immediate instead of sign-extend it.
+//
+// Note that FastISel does not currently understand IntImmLeaf and will not
+// generate code for rules that make use of it. As such, it does not make sense
+// to replace ImmLeaf with IntImmLeaf. However, replacing PatLeaf with an
+// IntImmLeaf will allow GlobalISel to import the rule.
+class IntImmLeaf<ValueType vt, code pred, SDNodeXForm xform = NOOP_SDNodeXForm>
+    : ImmLeaf<vt, pred, xform> {
+  let IsAPInt = 1;
+  let FastIselShouldIgnore = 1;
+}
+
+// An ImmLeaf except that Imm is an APFloat.
+//
+// Note that FastISel does not currently understand FPImmLeaf and will not
+// generate code for rules that make use of it.
+class FPImmLeaf<ValueType vt, code pred, SDNodeXForm xform = NOOP_SDNodeXForm>
+  : ImmLeaf<vt, pred, xform, fpimm> {
+  let IsAPFloat = 1;
+  let FastIselShouldIgnore = 1;
+}
 
 // Leaf fragments.
 
Index: lib/Target/AArch64/AArch64InstrFormats.td
===================================================================
--- lib/Target/AArch64/AArch64InstrFormats.td
+++ lib/Target/AArch64/AArch64InstrFormats.td
@@ -500,14 +500,14 @@
     let Name = "LogicalImm64Not";
   }
 }
-def logical_imm32 : Operand<i32>, PatLeaf<(imm), [{
-  return AArch64_AM::isLogicalImmediate(N->getZExtValue(), 32);
+def logical_imm32 : Operand<i32>, IntImmLeaf<i32, [{
+  return AArch64_AM::isLogicalImmediate(Imm.getZExtValue(), 32);
 }], logical_imm32_XFORM> {
   let PrintMethod = "printLogicalImm32";
   let ParserMatchClass = LogicalImm32Operand;
 }
-def logical_imm64 : Operand<i64>, PatLeaf<(imm), [{
-  return AArch64_AM::isLogicalImmediate(N->getZExtValue(), 64);
+def logical_imm64 : Operand<i64>, IntImmLeaf<i64, [{
+  return AArch64_AM::isLogicalImmediate(Imm.getZExtValue(), 64);
 }], logical_imm64_XFORM> {
   let PrintMethod = "printLogicalImm64";
   let ParserMatchClass = LogicalImm64Operand;
@@ -754,8 +754,8 @@
 
 // Floating-point immediate.
 def fpimm16 : Operand<f16>,
-              PatLeaf<(f16 fpimm), [{
-      return AArch64_AM::getFP16Imm(N->getValueAPF()) != -1;
+              FPImmLeaf<f16, [{
+      return AArch64_AM::getFP16Imm(Imm) != -1;
     }], SDNodeXForm<fpimm, [{
       APFloat InVal = N->getValueAPF();
       uint32_t enc = AArch64_AM::getFP16Imm(InVal);
@@ -765,8 +765,8 @@
   let PrintMethod = "printFPImmOperand";
 }
 def fpimm32 : Operand<f32>,
-              PatLeaf<(f32 fpimm), [{
-      return AArch64_AM::getFP32Imm(N->getValueAPF()) != -1;
+              FPImmLeaf<f32, [{
+      return AArch64_AM::getFP32Imm(Imm) != -1;
     }], SDNodeXForm<fpimm, [{
       APFloat InVal = N->getValueAPF();
       uint32_t enc = AArch64_AM::getFP32Imm(InVal);
@@ -776,8 +776,8 @@
   let PrintMethod = "printFPImmOperand";
 }
 def fpimm64 : Operand<f64>,
-              PatLeaf<(f64 fpimm), [{
-      return AArch64_AM::getFP64Imm(N->getValueAPF()) != -1;
+              FPImmLeaf<f64, [{
+      return AArch64_AM::getFP64Imm(Imm) != -1;
     }], SDNodeXForm<fpimm, [{
       APFloat InVal = N->getValueAPF();
       uint32_t enc = AArch64_AM::getFP64Imm(InVal);
@@ -792,8 +792,8 @@
   let PrintMethod = "printFPImmOperand";
 }
 
-def fpimm0 : PatLeaf<(fpimm), [{
-  return N->isExactlyValue(+0.0);
+def fpimm0 : FPImmLeaf<fAny, [{
+  return Imm.isExactlyValue(+0.0);
 }]>;
 
 // Vector lane operands
@@ -847,10 +847,9 @@
 // aaaaaaaa bbbbbbbb cccccccc dddddddd eeeeeeee ffffffff gggggggg hhhhhhhh
 // are encoded as the eight bit value 'abcdefgh'.
 def simdimmtype10 : Operand<i32>,
-                    PatLeaf<(f64 fpimm), [{
-      return AArch64_AM::isAdvSIMDModImmType10(N->getValueAPF()
-                                               .bitcastToAPInt()
-                                               .getZExtValue());
+                    FPImmLeaf<f64, [{
+      return AArch64_AM::isAdvSIMDModImmType10(
+                 Imm.bitcastToAPInt().getZExtValue());
     }], SDNodeXForm<fpimm, [{
       APFloat InVal = N->getValueAPF();
       uint32_t enc = AArch64_AM::encodeAdvSIMDModImmType10(N->getValueAPF()
Index: utils/TableGen/CodeGenDAGPatterns.h
===================================================================
--- utils/TableGen/CodeGenDAGPatterns.h
+++ utils/TableGen/CodeGenDAGPatterns.h
@@ -475,9 +475,14 @@
   /// appropriate.
   std::string getCodeToRunOnSDNode() const;
 
+  /// Get the data type of the argument to getImmediatePredicateCode().
+  std::string getImmType() const;
+
 private:
   std::string getPredCode() const;
   std::string getImmCode() const;
+  bool immCodeUsesAPInt() const;
+  bool immCodeUsesAPFloat() const;
 };
 
 
Index: utils/TableGen/CodeGenDAGPatterns.cpp
===================================================================
--- utils/TableGen/CodeGenDAGPatterns.cpp
+++ utils/TableGen/CodeGenDAGPatterns.cpp
@@ -862,6 +862,24 @@
   return PatFragRec->getRecord()->getValueAsString("ImmediateCode");
 }
 
+bool TreePredicateFn::immCodeUsesAPInt() const {
+  return getOrigPatFragRecord()->getRecord()->getValueAsBit("IsAPInt");
+}
+
+bool TreePredicateFn::immCodeUsesAPFloat() const {
+  bool Unset;
+  // The return value will be false when IsAPFloat is unset.
+  return getOrigPatFragRecord()->getRecord()->getValueAsBitOrUnset("IsAPFloat",
+                                                                   Unset);
+}
+
+std::string TreePredicateFn::getImmType() const {
+  if (immCodeUsesAPInt())
+    return "const APInt &";
+  if (immCodeUsesAPFloat())
+    return "const APFloat &";
+  return "int64_t";
+}
 
 /// isAlwaysTrue - Return true if this is a noop predicate.
 bool TreePredicateFn::isAlwaysTrue() const {
@@ -882,8 +900,13 @@
   // Handle immediate predicates first.
   std::string ImmCode = getImmCode();
   if (!ImmCode.empty()) {
-    std::string Result =
-      "    int64_t Imm = cast<ConstantSDNode>(Node)->getSExtValue();\n";
+    std::string Result = "    " + getImmType() + " Imm = ";
+    if (immCodeUsesAPFloat())
+      Result += "cast<ConstantFPSDNode>(Node)->getValueAPF();\n";
+    else if (immCodeUsesAPInt())
+      Result += "cast<ConstantSDNode>(Node)->getAPIntValue();\n";
+    else
+      Result += "cast<ConstantSDNode>(Node)->getSExtValue();\n";
     return Result + ImmCode;
   }
 
Index: utils/TableGen/GlobalISelEmitter.cpp
===================================================================
--- utils/TableGen/GlobalISelEmitter.cpp
+++ utils/TableGen/GlobalISelEmitter.cpp
@@ -1913,6 +1913,9 @@
   importImplicitDefRenderers(BuildMIAction &DstMIBuilder,
                              const std::vector<Record *> &ImplicitDefs) const;
 
+  void emitImmPredicates(raw_ostream &OS,
+                         std::function<bool(const Record *R)> Filter);
+
   /// Analyze pattern \p P, returning a matcher for it if possible.
   /// Otherwise, return an Error explaining why we don't support it.
   Expected<RuleMatcher> runOnPattern(const PatternToMatch &P);
@@ -2559,6 +2562,38 @@
   return std::move(M);
 }
 
+// Emit imm predicate table and an enum to reference them with.
+// The 'Predicate_' part of the name is redundant but eliminating it is more
+// trouble than it's worth.
+void GlobalISelEmitter::emitImmPredicates(
+    raw_ostream &OS, std::function<bool(const Record *R)> Filter) {
+  std::vector<const Record *> MatchedRecords;
+  const auto &Defs = RK.getAllDerivedDefinitions("PatFrag");
+  std::copy_if(Defs.begin(), Defs.end(), std::back_inserter(MatchedRecords),
+               [&](Record *Record) {
+                 return !Record->getValueAsString("ImmediateCode").empty() &&
+                        Filter(Record);
+               });
+
+  OS << "// PatFrag predicates.\n"
+     << "enum {\n";
+  StringRef EnumeratorSeparator = " = GIPFP_Invalid + 1,\n";
+  for (const auto *Record : MatchedRecords) {
+    OS << "  GIPFP_Predicate_" << Record->getName() << EnumeratorSeparator;
+    EnumeratorSeparator = ",\n";
+  }
+  OS << "};\n";
+  for (const auto *Record : MatchedRecords)
+    OS << "  static bool Predicate_" << Record->getName() << "(int64_t Imm) {"
+       << Record->getValueAsString("ImmediateCode") << "  }\n";
+  OS << "static InstructionSelector::ImmediatePredicateFn ImmPredicateFns[] = "
+        "{\n"
+     << "  nullptr,\n";
+  for (const auto *Record : MatchedRecords)
+    OS << "  Predicate_" << Record->getName() << ",\n";
+  OS << "};\n";
+}
+
 void GlobalISelEmitter::run(raw_ostream &OS) {
   // Track the GINodeEquiv definitions.
   gatherNodeEquivs();
@@ -2742,32 +2777,11 @@
   OS << "};\n"
      << "// See constructor for table contents\n\n";
 
-  // Emit imm predicate table and an enum to reference them with.
-  // The 'Predicate_' part of the name is redundant but eliminating it is more
-  // trouble than it's worth.
-  {
-    OS << "// PatFrag predicates.\n"
-       << "enum {\n";
-    StringRef EnumeratorSeparator = " = GIPFP_Invalid + 1,\n";
-    for (const auto *Record : RK.getAllDerivedDefinitions("PatFrag")) {
-      if (!Record->getValueAsString("ImmediateCode").empty()) {
-        OS << "  GIPFP_Predicate_" << Record->getName() << EnumeratorSeparator;
-        EnumeratorSeparator = ",\n";
-      }
-    }
-    OS << "};\n";
-  }
-  for (const auto *Record : RK.getAllDerivedDefinitions("PatFrag"))
-    if (!Record->getValueAsString("ImmediateCode").empty())
-      OS << "  static bool Predicate_" << Record->getName() << "(int64_t Imm) {"
-         << Record->getValueAsString("ImmediateCode") << "  }\n";
-  OS << "static InstructionSelector::ImmediatePredicateFn ImmPredicateFns[] = "
-        "{\n"
-     << "  nullptr,\n";
-  for (const auto *Record : RK.getAllDerivedDefinitions("PatFrag"))
-    if (!Record->getValueAsString("ImmediateCode").empty())
-      OS << "  Predicate_" << Record->getName() << ",\n";
-  OS << "};\n";
+  emitImmPredicates(OS, [](const Record *R) {
+    bool Unset;
+    return !R->getValueAsBitOrUnset("IsAPFloat", Unset) &&
+           !R->getValueAsBit("IsAPInt");
+  });
 
   OS << "bool " << Target.getName()
      << "InstructionSelector::selectImpl(MachineInstr &I) const {\n"