From cfa3c236b23aff80e48df11ef5833b7e63fab802 Mon Sep 17 00:00:00 2001
From: Duncan Sands <baldrick@free.fr>
Date: Tue, 8 Jul 2008 09:41:30 +0000
Subject: [PATCH] Add some helpers for manipulating function parameter
 attributes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53228 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/Function.h | 38 +++++++++++++++++++++++++++++---------
 lib/VMCore/Function.cpp | 28 +++++++++++-----------------
 2 files changed, 40 insertions(+), 26 deletions(-)

diff --git a/include/llvm/Function.h b/include/llvm/Function.h
index ef824579262..f48eb38d1da 100644
--- a/include/llvm/Function.h
+++ b/include/llvm/Function.h
@@ -174,29 +174,49 @@ public:
   /// addParamAttr - adds the attribute to the list of attributes.
   void addParamAttr(unsigned i, ParameterAttributes attr);
   
+  /// removeParamAttr - removes the attribute from the list of attributes.
+  void removeParamAttr(unsigned i, ParameterAttributes attr);
+
   /// @brief Extract the alignment for a call or parameter (0=unknown).
   unsigned getParamAlignment(unsigned i) const {
     return ParamAttrs.getParamAlignment(i);
   }
 
-  /// @brief Determine if the function cannot return.
-  bool doesNotReturn() const { return paramHasAttr(0, ParamAttr::NoReturn); }
-  void setDoesNotThrow(bool doesNotThrow = true);
-
-  /// @brief Determine if the function cannot unwind.
-  bool doesNotThrow() const {
-    return paramHasAttr(0, ParamAttr::NoUnwind);
-  }
-
   /// @brief Determine if the function does not access memory.
   bool doesNotAccessMemory() const {
     return paramHasAttr(0, ParamAttr::ReadNone);
   }
+  void setDoesNotAccessMemory(bool doesNotAccessMemory = true) {
+    if (doesNotAccessMemory) addParamAttr(0, ParamAttr::ReadNone);
+    else removeParamAttr(0, ParamAttr::ReadNone);
+  }
 
   /// @brief Determine if the function does not access or only reads memory.
   bool onlyReadsMemory() const {
     return doesNotAccessMemory() || paramHasAttr(0, ParamAttr::ReadOnly);
   }
+  void setOnlyReadsMemory(bool onlyReadsMemory = true) {
+    if (onlyReadsMemory) addParamAttr(0, ParamAttr::ReadOnly);
+    else removeParamAttr(0, ParamAttr::ReadOnly | ParamAttr::ReadNone);
+  }
+
+  /// @brief Determine if the function cannot return.
+  bool doesNotReturn() const {
+    return paramHasAttr(0, ParamAttr::NoReturn);
+  }
+  void setDoesNotReturn(bool doesNotReturn = true) {
+    if (doesNotReturn) addParamAttr(0, ParamAttr::NoReturn);
+    else removeParamAttr(0, ParamAttr::NoReturn);
+  }
+
+  /// @brief Determine if the function cannot unwind.
+  bool doesNotThrow() const {
+    return paramHasAttr(0, ParamAttr::NoUnwind);
+  }
+  void setDoesNotThrow(bool doesNotThrow = true) {
+    if (doesNotThrow) addParamAttr(0, ParamAttr::NoUnwind);
+    else removeParamAttr(0, ParamAttr::NoUnwind);
+  }
 
   /// @brief Determine if the function returns a structure through first 
   /// pointer argument.
diff --git a/lib/VMCore/Function.cpp b/lib/VMCore/Function.cpp
index 7533185be1d..1b4e39f952a 100644
--- a/lib/VMCore/Function.cpp
+++ b/lib/VMCore/Function.cpp
@@ -113,16 +113,13 @@ bool Argument::hasStructRetAttr() const {
 
 /// addAttr - Add a ParamAttr to an argument
 void Argument::addAttr(ParameterAttributes attr) {
-  getParent()->setParamAttrs(
-    getParent()->getParamAttrs().addAttr(getArgNo() + 1, attr));
-}
-  
-/// removeAttr - Remove a ParamAttr from an argument
-void Argument::removeAttr(ParameterAttributes attr) {
-  getParent()->setParamAttrs(
-    getParent()->getParamAttrs().removeAttr(getArgNo() + 1, attr));
+  getParent()->addParamAttr(getArgNo() + 1, attr);
 }
 
+/// removeAttr - Remove a ParamAttr from an argument
+void Argument::removeAttr(ParameterAttributes attr) {
+  getParent()->removeParamAttr(getArgNo() + 1, attr);
+}
 
 
 //===----------------------------------------------------------------------===//
@@ -231,21 +228,18 @@ void Function::dropAllReferences() {
   BasicBlocks.clear();    // Delete all basic blocks...
 }
 
-void Function::setDoesNotThrow(bool doesNotThrow) {
-  PAListPtr PAL = getParamAttrs();
-  if (doesNotThrow)
-    PAL = PAL.addAttr(0, ParamAttr::NoUnwind);
-  else
-    PAL = PAL.removeAttr(0, ParamAttr::NoUnwind);
-  setParamAttrs(PAL);
-}
-
 void Function::addParamAttr(unsigned i, ParameterAttributes attr) {
   PAListPtr PAL = getParamAttrs();
   PAL = PAL.addAttr(i, attr);
   setParamAttrs(PAL);
 }
 
+void Function::removeParamAttr(unsigned i, ParameterAttributes attr) {
+  PAListPtr PAL = getParamAttrs();
+  PAL = PAL.removeAttr(i, attr);
+  setParamAttrs(PAL);
+}
+
 // Maintain the collector name for each function in an on-the-side table. This
 // saves allocating an additional word in Function for programs which do not use
 // GC (i.e., most programs) at the cost of increased overhead for clients which