Make first substantial checkin of my port of ARM constant islands code to Mips.

Before I just ported the shell of the pass. I've tried to keep everything
nearly identical to the ARM version. I think it will be very easy to eventually
merge these two and create a new more general pass that other targets can
use. I have some improvements I would like to make to allow pools to 
be shared across functions and some other things. When I'm all done we
can think about making a more general pass. More to be ported but the
basic mechanism works now almost as good as gcc mips16.

llvm-svn: 193509

1 files changed, 20 insertions, 1 deletions

diff --git a/llvm/lib/Target/Mips/MipsAsmPrinter.h b/llvm/lib/Target/Mips/MipsAsmPrinter.h
index 5f6cac8f211..44b8b068dfa 100644
--- a/llvm/lib/Target/Mips/MipsAsmPrinter.h
+++ b/llvm/lib/Target/Mips/MipsAsmPrinter.h
@@ -42,6 +42,16 @@ private:
   // lowerOperand - Convert a MachineOperand into the equivalent MCOperand.
   bool lowerOperand(const MachineOperand &MO, MCOperand &MCOp);
 
+  /// MCP - Keep a pointer to constantpool entries of the current
+  /// MachineFunction.
+  const MachineConstantPool *MCP;
+
+  /// InConstantPool - Maintain state when emitting a sequence of constant
+  /// pool entries so we can properly mark them as data regions.
+  bool InConstantPool;
+
+  bool UsingConstantPools;
+
 public:
 
   const MipsSubtarget *Subtarget;
@@ -49,8 +59,11 @@ public:
   MipsMCInstLower MCInstLowering;
 
   explicit MipsAsmPrinter(TargetMachine &TM,  MCStreamer &Streamer)
-    : AsmPrinter(TM, Streamer), MCInstLowering(*this) {
+    : AsmPrinter(TM, Streamer), MCP(0), InConstantPool(false),
+      MCInstLowering(*this) {
     Subtarget = &TM.getSubtarget<MipsSubtarget>();
+    UsingConstantPools =
+      (Subtarget->inMips16Mode() && Subtarget->useConstantIslands());
   }
 
   virtual const char *getPassName() const {
@@ -59,6 +72,12 @@ public:
 
   virtual bool runOnMachineFunction(MachineFunction &MF);
 
+  virtual void EmitConstantPool() LLVM_OVERRIDE {
+    if (!UsingConstantPools)
+      AsmPrinter::EmitConstantPool();
+    // we emit constant pools customly!
+  }
+
   void EmitInstruction(const MachineInstr *MI);
   void printSavedRegsBitmask(raw_ostream &O);
   void printHex32(unsigned int Value, raw_ostream &O);