[SubZero] Implement load and store for MIPS

src/IceTargetLoweringMIPS32.h

 //===- subzero/src/IceTargetLoweringMIPS32.h - MIPS32 lowering ---*- C++-*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 83 matching lines @@
     return (typeWidthInBytes(Ty) + 3) & ~3;
   }
   uint32_t getStackAlignment() const override;
   void reserveFixedAllocaArea(size_t Size, size_t Align) override {
     FixedAllocaSizeBytes = Size;
     assert(llvm::isPowerOf2_32(Align));
     FixedAllocaAlignBytes = Align;
     PrologEmitsFixedAllocas = true;
   }
   int32_t getFrameFixedAllocaOffset() const override {
-    // TODO(sehr): Implement fixed stack layout.
-    llvm::report_fatal_error("Not yet implemented");
-    return 0;
+    return FixedAllocaSizeBytes - (SpillAreaSizeBytes - MaxOutArgsSizeBytes);
   }
 
   uint32_t maxOutArgsSizeBytes() const override { return MaxOutArgsSizeBytes; }
 
   bool shouldSplitToVariable64On32(Type Ty) const override {
     return Ty == IceType_i64;
   }
 
   // TODO(ascull): what is the best size of MIPS?
   SizeT getMinJumpTableSize() const override { return 3; }
@@ skipping 324 matching lines @@
   /// the helpers will create a new Operand and emit instructions that
   /// guarantee that the Operand kind is one of those indicated by the
   /// LegalMask (a bitmask of allowed kinds).  If the input Operand is known
   /// to already meet the constraints, it may be simply returned as the result,
   /// without creating any new instructions or operands.
   enum OperandLegalization {
     Legal_None = 0,
     Legal_Reg = 1 << 0, // physical register, not stack location
     Legal_Imm = 1 << 1,
     Legal_Mem = 1 << 2,
+    Legal_Rematerializable = 1 << 3,
     Legal_Default = ~Legal_None
   };
   typedef uint32_t LegalMask;
   Operand *legalize(Operand *From, LegalMask Allowed = Legal_Default,
                     RegNumT RegNum = RegNumT());
 
   Variable *legalizeToVar(Operand *From, RegNumT RegNum = RegNumT());
 
   Variable *legalizeToReg(Operand *From, RegNumT RegNum = RegNumT());
 
@@ skipping 266 matching lines @@
   explicit TargetHeaderMIPS32(GlobalContext *Ctx);
 
 private:
   ~TargetHeaderMIPS32() = default;
 };
 
 } // end of namespace MIPS32
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICETARGETLOWERINGMIPS32_H