Apply suggestions from code review

Co-authored-by: Josh Triplett <[email protected]>

Author: chorman0773

src/inline-assembly.md

@@ -87,7 +87,7 @@ On x86, the `.intel_syntax noprefix` mode of GAS is used by default.
 On ARM, the `.syntax unified` mode is used.
 These targets impose an additional restriction on the assembly code: any assembler state (e.g. the current section which can be changed with `.section`) must be restored to its original value at the end of the asm string.
 Assembly code that does not conform to the GAS syntax will result in assembler-specific behavior. 
-Further constraints on the directives used by the assembly are indicated by [Directives Support](#directives-support). 
+Further constraints on the directives used by inline assembly are indicated by [Directives Support](#directives-support). 
 
 [format-syntax]: ../std/fmt/index.html#syntax
 [rfc-2795]: https://github.com/rust-lang/rfcs/pull/2795
@@ -481,9 +481,11 @@ To avoid undefined behavior, these rules must be followed when using function-sc
 
 ### Directives Support
 
-Inline ASM supports a subset of the directives supported by both GNU AS and LLVM's internal assembler, given as follows.
+Inline assembly supports a subset of the directives supported by both GNU AS and LLVM's internal assembler, given as follows.
 The result of using other directives is assembler-specific (and may cause an error, or may be accepted as-is).
 
+If inline assembly includes any "stateful" directive that modifies how subsequent assembly is processed, the block must undo the effects of any such directives before the inline assembly ends.
+
 The following directives are guaranteed to be supported by the assembler:
 
 
@@ -515,6 +517,7 @@ The following directives are guaranteed to be supported by the assembler:
 - `.section`
 - `.pushsection`
 - `.popsection`
+- `.subsection`
 - `.text`
 - `.bss`
 - `.data`
@@ -584,9 +587,9 @@ On targets with structured exception Handling, the following additional directiv
 - `.seh_stackalloc`
 
 
-##### x86
+##### x86 (32-bit and 64-bit)
 
-On x86, the following additional directives are guaranteed to be supported:
+On x86 targets, both 32-bit and 64-bit, the following additional directives are guaranteed to be supported:
 - `.nops`
 
 On x86 for `global_asm!` only, the following additional directives are guaranteed to be supported (it is unspecified whether `.code16` or `.code32` are supported for `asm!()`):
@@ -610,3 +613,4 @@ On ARM, the following additional directives are guaranteed to be supported:
 - `.fnend`
 - `.save`
 - `.movsp`
+- `.even`