Allow readonly functions to unwind exceptions. Teach
the optimizers about this. For example, a readonly
function with no uses cannot be removed unless it is
also marked nounwind.
llvm-svn: 71071
diff --git a/llvm/lib/VMCore/Instruction.cpp b/llvm/lib/VMCore/Instruction.cpp
index f33c1a2..9e030b7 100644
--- a/llvm/lib/VMCore/Instruction.cpp
+++ b/llvm/lib/VMCore/Instruction.cpp
@@ -320,6 +320,14 @@
}
}
+/// mayThrow - Return true if this instruction may throw an exception.
+///
+bool Instruction::mayThrow() const {
+ if (const CallInst *CI = dyn_cast<CallInst>(this))
+ return !CI->doesNotThrow();
+ return false;
+}
+
/// isAssociative - Return true if the instruction is associative:
///
/// Associative operators satisfy: x op (y op z) === (x op y) op z)