minor improvements

Author: mark-i-m

src/SUMMARY.md

@@ -54,7 +54,7 @@
 - [Constant evaluation](./const-eval.md)
     - [miri const evaluator](./miri.md)
 - [Parameter Environments](./param_env.md)
-- [Generating LLVM IR](./codegen.md)
+- [Code Generation](./codegen.md)
 - [Emitting Diagnostics](./diag.md)
 
 ---

src/codegen.md

@@ -3,6 +3,11 @@
 Code generation or "codegen" is the part of the compiler that actually
 generates an executable binary. rustc uses LLVM for code generation.
 
+> NOTE: If you are looking for hints on how to debug code generation bugs,
+> please see [this section of the debugging chapter][debug].
+
+[debug]: compiler-debugging.html#debugging-llvm
+
 ## What is LLVM?
 
 All of the preceeding chapters of this guide have one thing in common: we never