Subzero: Use a setcc sequence for better icmp lowering.

src/IceInstX8632.h

 //===- subzero/src/IceInstX8632.h - x86-32 machine instructions -*- C++ -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file declares the InstX8632 and OperandX8632 classes and
@@ skipping 224 matching lines @@
     Psll,
     Psra,
     Psrl,
     Psub,
     Push,
     Pxor,
     Ret,
     Rol,
     Sar,
     Sbb,
+    Setcc,
     Shl,
     Shld,
     Shr,
     Shrd,
     Shufps,
     Sqrtss,
     Store,
     StoreP,
     StoreQ,
     Sub,
@@ skipping 1323 matching lines @@
   void emit(const Cfg *Func) const override;
   void emitIAS(const Cfg *Func) const override;
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return isClassof(Inst, Ret); }
 
 private:
   InstX8632Ret(Cfg *Func, Variable *Source);
   ~InstX8632Ret() override {}
 };
 
+// Conditional set-byte instruction.
+class InstX8632Setcc : public InstX8632 {
+  InstX8632Setcc() = delete;
+  InstX8632Setcc(const InstX8632Cmov &) = delete;
+  InstX8632Setcc &operator=(const InstX8632Setcc &) = delete;
+
+public:
+  static InstX8632Setcc *create(Cfg *Func, Variable *Dest,
+                                CondX86::BrCond Cond) {
+    return new (Func->allocate<InstX8632Setcc>())
+        InstX8632Setcc(Func, Dest, Cond);
+  }
+  void emit(const Cfg *Func) const override;
+  void emitIAS(const Cfg *Func) const override;
+  void dump(const Cfg *Func) const override;
+  static bool classof(const Inst *Inst) { return isClassof(Inst, Setcc); }
+
+private:
+  InstX8632Setcc(Cfg *Func, Variable *Dest, CondX86::BrCond Cond);
+  ~InstX8632Setcc() override {}
+
+  const CondX86::BrCond Condition;
+};
+
 // Exchanging Add instruction.  Exchanges the first operand (destination
 // operand) with the second operand (source operand), then loads the sum
 // of the two values into the destination operand. The destination may be
 // a register or memory, while the source must be a register.
 //
 // Both the dest and source are updated. The caller should then insert a
 // FakeDef to reflect the second udpate.
 class InstX8632Xadd : public InstX8632Lockable {
   InstX8632Xadd() = delete;
   InstX8632Xadd(const InstX8632Xadd &) = delete;
@@ skipping 81 matching lines @@
 template <> void InstX8632Pinsr::emitIAS(const Cfg *Func) const;
 template <> void InstX8632Movsx::emitIAS(const Cfg *Func) const;
 template <> void InstX8632Movzx::emitIAS(const Cfg *Func) const;
 template <> void InstX8632Pmull::emitIAS(const Cfg *Func) const;
 template <> void InstX8632Pshufd::emitIAS(const Cfg *Func) const;
 template <> void InstX8632Shufps::emitIAS(const Cfg *Func) const;
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICEINSTX8632_H