Remove the "VM" and "bytecode" features (#745)

* Remove the "VM" and "bytecode" features

The "bytecode" in `bc.{h,cpp}` was an initial attempt at a serialized encoding for the Slang IR, but we now have the `ir-serialize.{h,cpp}` approach which was has been kept up to date much better.

Similarly, the "VM" in `vm.{h,cpp}` was intended to be a system for interpreting Slang code in the bytecode format directly (so that you could load and evaluate code in a Slang module in a lightweight fashion). This never got used past a single test, which we eventually disabled.

There are good ideas in some of this code, but at this point the implementations have bit-rotted to a point where trying to maintain it is more costly than it would be to re-created it if/when we ever decide these features are important again.

* fixup: remove slang-eval-test from Makefile

1 files changed, 14 insertions, 1 deletions

diff --git a/source/slang/ir.cpp b/source/slang/ir.cpp
index 2f16f4ebc..c0715fca3 100644
--- a/source/slang/ir.cpp
+++ b/source/slang/ir.cpp
@@ -2617,7 +2617,20 @@ namespace Slang
         }
     }
 
-    bool opHasResult(IRInst* inst);
+    bool opHasResult(IRInst* inst)
+    {
+        auto type = inst->getDataType();
+        if (!type) return false;
+
+        // As a bit of a hack right now, we need to check whether
+        // the function returns the distinguished `Void` type,
+        // since that is conceptually the same as "not returning
+        // a value."
+        if(type->op == kIROp_VoidType)
+            return false;
+
+        return true;
+    }
 
     bool instHasUses(IRInst* inst)
     {