From c7c21969e889f9b15827cb8c4d2da818df8cb596 Mon Sep 17 00:00:00 2001
From: Roland Conybeare <rconybeare@gmail.com>
Date: Fri, 21 Jun 2024 14:05:26 -0400
Subject: [PATCH] xo-expression: + llvmintrinsics enum

---
 include/xo/expression/llvmintrinsic.hpp | 92 +++++++++++++++++++++++++
 1 file changed, 92 insertions(+)
 create mode 100644 include/xo/expression/llvmintrinsic.hpp

diff --git a/include/xo/expression/llvmintrinsic.hpp b/include/xo/expression/llvmintrinsic.hpp
new file mode 100644
index 00000000..37f231fe
--- /dev/null
+++ b/include/xo/expression/llvmintrinsic.hpp
@@ -0,0 +1,92 @@
+/** @file llvmintrinsic.hpp
+ *
+ *  Author: Roland Conybeare
+ **/
+
+#pragma once
+
+//#include <cstdint>
+
+namespace xo {
+    namespace ast {
+        /** @enum llvminstrinsic
+         *  @brief enum to identify an LLVM instrinsic, e.g. @c IRBuilder::CreateFAdd
+         *
+         *  Associate an @c llvminstrinsic with an AST @c Primitive p.
+         *  Later, in @c xo::jit::IrPipeline
+         *  - when generating code for @c xo::ast::Apply
+         *  - with *p* is in the function-call position
+         *  can use the associated llvm instrinsic instead of generating a function call
+         *  @c Primitive::value
+         *
+         *  @note llvm will still need to use @c Primitive::value,  for example
+         *  when handling an @c xo::ast::Apply instance where the function position
+         *  is a computed function.
+         *  @endnote
+         *
+         *  @note
+         *  NSW stands for 'no signed wrap' -> poison value if overflow (costs more)
+         *  NUW stands for 'no unsigned wrap' -> poison value if overflow (costs more)
+         *  @endnote
+         **/
+        enum class llvmintrinsic {
+            /** sentinel value **/
+            invalid = -1,
+
+            /** -> IRBuilder::CreateAdd (add 2 integers, overflow silently) **/
+            i_add,
+
+            /** -> IRBuilder::CreateMul (multiply 2 integers, overflow silently) **/
+            i_mul,
+
+            /** -> IRBuilder::CreateFadd (add 2 floating-point numbers) **/
+            fp_add,
+
+            /** -> IRBuilder::CreateFmul (multiply 2 floating-point numbers) **/
+            fp_mul,
+
+            /**
+             *  want to do whatever llvm IR @c llvm.sqrt.f64 and friends do.
+             *  Not sure if that's an always-available function of something else
+             **/
+            fp_sqrt,
+
+            /** WIP **/
+            fp_pow,
+
+            /** WIP **/
+            fp_sin,
+
+            /** WIP **/
+            fp_cos,
+
+            /** WIP **/
+            fp_tan,
+
+            /** not an intrinsic.  comes last, counts entries **/
+            n_intrinsic
+        };
+
+        inline const char *
+        llvmintrinsic2str(llvmintrinsic x)
+        {
+            switch(x) {
+            case llvmintrinsic::invalid: return "?llvminstrinsic";
+            case llvmintrinsic::i_add: return "i_add";
+            case llvmintrinsic::i_mul: return "i_mul";
+            case llvmintrinsic::fp_add: return "fp_add";
+            case llvmintrinsic::fp_mul: return "fp_mul";
+            case llvmintrinsic::fp_sqrt: return "fp_sqrt";
+            case llvmintrinsic::fp_pow: return "fp_pow";
+            case llvmintrinsic::fp_sin: return "fp_sin";
+            case llvmintrinsic::fp_cos: return "fp_cos";
+            case llvmintrinsic::fp_tan: return "fp_tan";
+            default: break;
+            }
+
+            return "???llvmintrinsic???";
+        } /*llvmintrinsic2str*/
+    } /*namespace ast*/
+} /*namespace xo*/
+
+/** end llvmintrinsic.hpp **/