Create frontends/pytorch directory.

* Adds/updates readmes with some notes about code organization and direction.
* Meant to prepare a space for upcoming integration of #30.

Author: stellaraccident

README.md

@@ -11,7 +11,8 @@ In addition to providing a bridge to a variety of Python based numerical program
 
 ## Framework integrations
 
-* Coming soon
+* [PyTorch](frontends/pytorch/README.md) -- Experimental integration for
+  extracting programs from PyTorch.
 
 ## Python language compiler tookit
 

frontends/README.md

@@ -0,0 +1,17 @@
+# NPComp - Frontends
+
+NPComp maintains in-tree frontends for various popular numeric-python based
+frameworks. In general these are:
+
+* Considered optional components
+* Target dialects maintained at the top-level of the project
+* Maintained in isolation so as to facilitate moving them out to dedicated
+  projects at an appropriate point of the lifecycle (i.e. if NPComp is
+  successful as a general purpose target for such frameworks, then it may
+  make sense to contribute/build each frontend to their respective up-stream
+  project).
+
+Frontends try to stylistically fit into the outer project except for when it
+is more clear/advantageous to align them with the conventions of the source
+project. This is approached on a case by case basis as needed. Deviations
+should be documented in a local style guide for the frontend.

frontends/pytorch/README.md

@@ -0,0 +1,17 @@
+# NPComp - PyTorch frontend integration
+
+This directory contains optional components for interfacing PyTorch to NPComp.
+Integration is targeted at multiple levels:
+
+* Via program capture with a ATen pseudo-device.
+* Via IR-level integration with PyTorch (via tracing or scripting interfaces).
+* Interfaces to facilitate checking against reference implementations and
+  verification.
+
+In all situations, the target dialects are maintained in the outer project,
+along with their lowerings to common intermediate dialects and backends. This
+directory should be purely about interfacing with the PyTorch/LibTorch
+components for extracting and executing programs.
+
+See the [overall documentation for frontends](../README.md) for further details
+about code layout and integration philosophy.