Initial (#1586)

Add additional documentation to explain the passes.

src/include/migraphx/memory_coloring.hpp

@@ -33,7 +33,8 @@ inline namespace MIGRAPHX_INLINE_NS {
 struct module;
 
 /**
- * Remove memory allocations. It uses graph coloring to find memory allocations that can be reused.
+ * Remove multiple memory allocations using graph coloring to find memory allocations that can be
+ * reused.
  */
 struct memory_coloring
 {

src/include/migraphx/replace_allocate.hpp

@@ -32,6 +32,9 @@ inline namespace MIGRAPHX_INLINE_NS {
 
 struct module;
 
+/**
+ *  Replace `allocate` instructions with target allocations or output parameters.
+ */
 struct replace_allocate
 {
     allocation_model model;

src/targets/gpu/include/migraphx/gpu/lowering.hpp

@@ -33,6 +33,13 @@ inline namespace MIGRAPHX_INLINE_NS {
 struct module;
 
 namespace gpu {
+
+/**
+ * Compiler pass that makes GPU-specific instruction changes.
+ * * Copies to and from the device if `offload_copy` is true.
+ * * Maps instructions to their GPU-specific counterparts.
+ * * Inserts `allocate` instructions before GPU operators.
+ */
 struct lowering
 {
     context* ctx;