Divergence analysis for GPU programs

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

diff --git a/include/llvm/CodeGen/IntrinsicLowering.h b/include/llvm/CodeGen/IntrinsicLowering.h
index 7f0cd81ca6e7ff715bc1ac01f3d13e90ac01feb5..9e6ab7d45977e960b4dae4231106e92e32a93d33 100644 (file)
--- a/include/llvm/CodeGen/IntrinsicLowering.h
+++ b/include/llvm/CodeGen/IntrinsicLowering.h
@@ -1,63 +1,58 @@
-//===-- llvm/IntrinsicLowering.h - Intrinsic Function Lowering --*- C++ -*-===//
-// 
+//===-- IntrinsicLowering.h - Intrinsic Function Lowering -------*- C++ -*-===//
+//
 //                     The LLVM Compiler Infrastructure
 //
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-// 
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
 //===----------------------------------------------------------------------===//
-// 
+//
 // This file defines the IntrinsicLowering interface.  This interface allows
 // addition of domain-specific or front-end specific intrinsics to LLVM without
-// having to modify all of the target-machines to support the new intrinsic.
-// Later, as desired, code generators can incrementally add support for
-// particular intrinsic functions, as desired, to generate better code.
-//
-// If a code generator cannot handle or does not know about an intrinsic
-// function, it will use the intrinsic lowering interface to change an intrinsic
-// function name into a concrete function name which can be used to implement
-// the functionality of the intrinsic.  For example, llvm.acos can be
-// implemented as a call to the math library 'acos' function if the target
-// doesn't have hardware support for the intrinsic, or if it has not yet been
-// implemented yet.
-//
-// Another use for this interface is the addition of domain-specific intrinsics.
-// The default implementation of this interface would then lower the intrinsics
-// to noop calls, allowing the direct execution of programs with instrumentation
-// or other hooks placed in them.  When a specific tool or flag is used, a
-// different implementation of these interfaces may be used, which activates the
-// intrinsics in some way.
+// having to modify all of the C backend or interpreter.
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_INTRINSICLOWERING_H
-#define LLVM_INTRINSICLOWERING_H
+#ifndef LLVM_CODEGEN_INTRINSICLOWERING_H
+#define LLVM_CODEGEN_INTRINSICLOWERING_H
+
+#include "llvm/IR/Intrinsics.h"
 
 namespace llvm {
   class CallInst;
-  
-  struct IntrinsicLowering {
-    virtual ~IntrinsicLowering() {}
+  class Module;
+  class DataLayout;
+
+  class IntrinsicLowering {
+    const DataLayout& DL;
+
+    
+    bool Warned;
+  public:
+    explicit IntrinsicLowering(const DataLayout &DL) :
+      DL(DL), Warned(false) {}
 
-    /// LowerIntrinsicCall - This method returns the LLVM function which should
-    /// be used to implement the specified intrinsic function call.  If an
-    /// intrinsic function must be implemented by the code generator (such as
-    /// va_start), this function should print a message and abort.
+    /// AddPrototypes - This method, if called, causes all of the prototypes
+    /// that might be needed by an intrinsic lowering implementation to be
+    /// inserted into the module specified.
+    void AddPrototypes(Module &M);
+
+    /// LowerIntrinsicCall - This method replaces a call with the LLVM function
+    /// which should be used to implement the specified intrinsic function call.
+    /// If an intrinsic function must be implemented by the code generator 
+    /// (such as va_start), this function should print a message and abort.
     ///
     /// Otherwise, if an intrinsic function call can be lowered, the code to
     /// implement it (often a call to a non-intrinsic function) is inserted
     /// _after_ the call instruction and the call is deleted.  The caller must
     /// be capable of handling this kind of change.
     ///
-    virtual void LowerIntrinsicCall(CallInst *CI) = 0;
-  };
+    void LowerIntrinsicCall(CallInst *CI);
 
-  /// DefaultIntrinsicLower - This is the default intrinsic lowering pass which
-  /// is used if no other one is specified.  Custom intrinsic lowering
-  /// implementations should pass any unhandled intrinsics to this
-  /// implementation to allow for future extensibility.
-  struct DefaultIntrinsicLowering : public IntrinsicLowering {
-    virtual void LowerIntrinsicCall(CallInst *CI);    
+    /// LowerToByteSwap - Replace a call instruction into a call to bswap
+    /// intrinsic. Return false if it has determined the call is not a
+    /// simple integer bswap.
+    static bool LowerToByteSwap(CallInst *CI);
   };
 }