[Statepoints 2/4] Statepoint infrastructure for garbage collection: MI & x86-64 Backend

[oota-llvm.git] / include / llvm / CodeGen / StackMaps.h

diff --git a/include/llvm/CodeGen/StackMaps.h b/include/llvm/CodeGen/StackMaps.h
index e343980d2abec10148df1571b1d429bc43e870f1..4e48afe140042b2bf25fcd8155687e03c24d42bd 100644 (file)
--- a/include/llvm/CodeGen/StackMaps.h
+++ b/include/llvm/CodeGen/StackMaps.h
@@ -81,6 +81,52 @@ public:
   unsigned getNextScratchIdx(unsigned StartIdx = 0) const;
 };
 
+/// MI-level Statepoint operands
+///
+/// Statepoint operands take the form:
+///   <num call arguments>, <call target>, [call arguments],
+///   <StackMaps::ConstantOp>, <flags>,
+///   <StackMaps::ConstantOp>, <num other args>, [other args],
+///   [gc values]
+class StatepointOpers {
+private:
+  enum {
+    NCallArgsPos = 0,
+    CallTargetPos = 1
+  };
+
+public:
+  explicit StatepointOpers(const MachineInstr *MI):
+    MI(MI) { }
+
+  /// Get starting index of non call related arguments
+  /// (statepoint flags, vm state and gc state).
+  unsigned getVarIdx() const {
+    return MI->getOperand(NCallArgsPos).getImm() + 2;
+  }
+
+  /// Returns the index of the operand containing the number of non-gc non-call
+  /// arguments. 
+  unsigned getNumVMSArgsIdx() const {
+    return getVarIdx() + 3;
+  }
+
+  /// Returns the number of non-gc non-call arguments attached to the
+  /// statepoint.  Note that this is the number of arguments, not the number of
+  /// operands required to represent those arguments.
+  unsigned getNumVMSArgs() const {
+    return MI->getOperand(getNumVMSArgsIdx()).getImm();
+  }
+
+  /// Returns the target of the underlying call.
+  const MachineOperand &getCallTarget() const {
+    return MI->getOperand(CallTargetPos);
+  }
+
+private:
+  const MachineInstr *MI;
+};
+
 class StackMaps {
 public:
   struct Location {
@@ -132,6 +178,9 @@ public:
   /// \brief Generate a stackmap record for a patchpoint instruction.
   void recordPatchPoint(const MachineInstr &MI);
 
+  /// \brief Generate a stackmap record for a statepoint instruction.
+  void recordStatepoint(const MachineInstr &MI);
+
   /// If there is any stack map data, create a stack map section and serialize
   /// the map info into it. This clears the stack map data structures
   /// afterwards.
@@ -139,7 +188,6 @@ public:
 
 private:
   static const char *WSMP;
-
   typedef SmallVector<Location, 8> LocationVec;
   typedef SmallVector<LiveOutReg, 8> LiveOutVec;
   typedef MapVector<uint64_t, uint64_t> ConstantPool;