[LFI] Update docs based on feedback

Author: zyedidia

llvm/docs/CodeGenerator.rst

@@ -2493,9 +2493,10 @@ The AMDGPU code generator lives in the ``lib/Target/AMDGPU``
 directory. This code generator is capable of targeting a variety of
 AMD GPU processors. Refer to :doc:`AMDGPUUsage` for more information.
 
-The Lightweight Fault Isolation (LFI) backend
----------------------------------------------
+The Lightweight Fault Isolation (LFI) sub-architecture
+------------------------------------------------------
 
-LFI is a backend that allows programs compiled for the target to run in a
-sandboxed environment that is within the same address space as host code. Refer
-to :doc:`LFI` for more information about the LFI backend.
+LFI is a sub-architecture available for certain backends that allows programs
+compiled for the target to run in a sandboxed environment that is within the
+same address space as host code. Refer to :doc:`LFI` for more information about
+LFI.

llvm/docs/LFI.rst

@@ -24,7 +24,7 @@ LFI aims for the following goals:
 * Performance: LFI aims for minimal overhead vs. unsandboxed code.
 * Security: The LFI runtime and compiler elements aim to be simple and
   verifiable when possible.
-* Usability: LFI aims to make it easy as possible to used retrofit sandboxing,
+* Usability: LFI aims to make it as easy as possible to retrofit sandboxing,
   i.e., to migrate from unsandboxed to sandboxed libraries with minimal effort.
 
 When building a program for the LFI target the compiler is designed to ensure
@@ -116,10 +116,10 @@ Control flow
 ~~~~~~~~~~~~
 
 Indirect branches get rewritten to branch through register ``x28``, which must
-always contain an address within the sandbox. An ``add`` is used to safely load
-``x28`` with the destination address. Since ``ret`` uses ``x30`` by default,
-which already must contain an address within the sandbox, it does not require
-any rewrite.
+always contain an address within the sandbox. An ``add`` is used to safely
+update ``x28`` with the destination address. Since ``ret`` uses ``x30`` by
+default, which already must contain an address within the sandbox, it does not
+require any rewrite.
 
 +--------------------+---------------------------+
 |      Original      |         Rewritten         |
@@ -220,7 +220,7 @@ Stack pointer modification
 ~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 When the stack pointer is modified, we write the modified value to a temporary,
-before loading it back into ``sp`` with a safe ``add``.
+before moving it back into ``sp`` with a safe ``add``.
 
 +------------------------------+-------------------------------+
 |           Original           |           Rewritten           |