Add helper functions to get range attribute

Author: andjo403

llvm/include/llvm/IR/Argument.h

@@ -16,9 +16,12 @@
 #include "llvm/ADT/Twine.h"
 #include "llvm/IR/Attributes.h"
 #include "llvm/IR/Value.h"
+#include <optional>
 
 namespace llvm {
 
+class ConstantRange;
+
 /// This class represents an incoming formal argument to a Function. A formal
 /// argument, since it is ``formal'', does not contain an actual value but
 /// instead represents the type, argument number, and attributes of an argument
@@ -67,6 +70,10 @@ class Argument final : public Value {
   /// disallowed floating-point values. Otherwise, fcNone is returned.
   FPClassTest getNoFPClass() const;
 
+  /// If this argument has a range attribute, return the value range of the
+  /// argument. Otherwise, std::nullopt is returned.
+  std::optional<ConstantRange> getRange() const;
+
   /// Return true if this argument has the byval attribute.
   bool hasByValAttr() const;
 

llvm/include/llvm/IR/InstrTypes.h

@@ -43,6 +43,7 @@ namespace llvm {
 class StringRef;
 class Type;
 class Value;
+class ConstantRange;
 
 namespace Intrinsic {
 typedef unsigned ID;
@@ -1917,7 +1918,7 @@ class CallBase : public Instruction {
 
     // Look at the callee, if available.
     if (const Function *F = getCalledFunction())
-      return F->getAttributes().getRetAttr(Kind);
+      return F->getRetAttribute(Kind);
     return Attribute();
   }
 
@@ -2154,6 +2155,10 @@ class CallBase : public Instruction {
   /// parameter.
   FPClassTest getParamNoFPClass(unsigned i) const;
 
+  /// If this return value has a range attribute, return the value range of the
+  /// argument. Otherwise, std::nullopt is returned.
+  std::optional<ConstantRange> getRange() const;
+
   /// Return true if the return value is known to be not null.
   /// This may be because it has the nonnull attribute, or because at least
   /// one byte is dereferenceable and the pointer is in addrspace(0).

llvm/lib/Analysis/InstructionSimplify.cpp

@@ -3736,15 +3736,10 @@ static std::optional<ConstantRange> getRange(Value *V,
     if (MDNode *MD = IIQ.getMetadata(I, LLVMContext::MD_range))
       return getConstantRangeFromMetadata(*MD);
 
-  Attribute Range;
-  if (const Argument *A = dyn_cast<Argument>(V)) {
-    Range = A->getAttribute(llvm::Attribute::Range);
-  } else if (const CallBase *CB = dyn_cast<CallBase>(V)) {
-    Range = CB->getRetAttr(llvm::Attribute::Range);
-  }
-
-  if (Range.isValid())
-    return Range.getRange();
+  if (const Argument *A = dyn_cast<Argument>(V))
+    return A->getRange();
+  else if (const CallBase *CB = dyn_cast<CallBase>(V))
+    return CB->getRange();
 
   return std::nullopt;
 }

llvm/lib/IR/Function.cpp

@@ -24,6 +24,7 @@
 #include "llvm/IR/Attributes.h"
 #include "llvm/IR/BasicBlock.h"
 #include "llvm/IR/Constant.h"
+#include "llvm/IR/ConstantRange.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/GlobalValue.h"
@@ -256,6 +257,13 @@ FPClassTest Argument::getNoFPClass() const {
   return getParent()->getParamNoFPClass(getArgNo());
 }
 
+std::optional<ConstantRange> Argument::getRange() const {
+  const Attribute RangeAttr = getAttribute(llvm::Attribute::Range);
+  if (RangeAttr.isValid())
+    return RangeAttr.getRange();
+  return std::nullopt;
+}
+
 bool Argument::hasNestAttr() const {
   if (!getType()->isPointerTy()) return false;
   return hasAttribute(Attribute::Nest);

llvm/lib/IR/Instructions.cpp

@@ -19,6 +19,7 @@
 #include "llvm/IR/Attributes.h"
 #include "llvm/IR/BasicBlock.h"
 #include "llvm/IR/Constant.h"
+#include "llvm/IR/ConstantRange.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/DerivedTypes.h"
@@ -395,6 +396,13 @@ FPClassTest CallBase::getParamNoFPClass(unsigned i) const {
   return Mask;
 }
 
+std::optional<ConstantRange> CallBase::getRange() const {
+  const Attribute RangeAttr = getRetAttr(llvm::Attribute::Range);
+  if (RangeAttr.isValid())
+    return RangeAttr.getRange();
+  return std::nullopt;
+}
+
 bool CallBase::isReturnNonNull() const {
   if (hasRetAttr(Attribute::NonNull))
     return true;