[llvm] Proofread Extensions.rst (llvm#166716)

Author: kazutakahirata

llvm/docs/Extensions.rst

@@ -274,13 +274,13 @@ This would be equivalent to the following raw assembly:
 
 The following directives are specified:
 
-  - lib
+  - ``lib``
 
     The parameter identifies a library to be linked against.  The library will
     be looked up in the default and any specified library search paths
     (specified to this point).
 
-  - libpath
+  - ``libpath``
 
     The parameter identifies an additional library search path to be considered
     when looking up libraries after the inclusion of this option.
@@ -327,13 +327,13 @@ The contents of the section shall be a sequence of ``Elf_CGProfile`` entries.
     Elf_Xword cgp_weight;
   } Elf_CGProfile;
 
-cgp_from
+``cgp_from``
   The symbol index of the source of the edge.
 
-cgp_to
+``cgp_to``
   The symbol index of the destination of the edge.
 
-cgp_weight
+``cgp_weight``
   The weight of the edge.
 
 This is represented in assembly as:
@@ -352,7 +352,7 @@ table.
 ``SHT_LLVM_ADDRSIG`` Section (address-significance table)
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-This section is used to mark symbols as address-significant, i.e. the address
+This section is used to mark symbols as address-significant, i.e., the address
 of the symbol is used in a comparison or leaks outside the translation unit. It
 has the same meaning as the absence of the LLVM attributes ``unnamed_addr``
 and ``local_unnamed_addr``.
@@ -519,11 +519,11 @@ those bits are:
 #. Basic Block Frequencies - Encoded as raw block frequency value taken from
    MBFI analysis. This value is an integer that encodes the relative frequency
    compared to the entry block. More information can be found in
-   'llvm/Support/BlockFrequency.h'.
+   ``llvm/Support/BlockFrequency.h``.
 
 #. Branch Probabilities - Encoded as raw numerator for branch probability
    taken from MBPI analysis. This value is the numerator for a fixed point ratio
-   defined in 'llvm/Support/BranchProbability.h'. It indicates the probability
+   defined in ``llvm/Support/BranchProbability.h``. It indicates the probability
    that the block is followed by a given successor block during execution.
 
 This extra data requires version 2 or above. This is necessary since successors
@@ -726,7 +726,7 @@ Syntax:
 Syntax:
   ``.cv_fpo_data`` *procsym*
 
-Target Specific Behaviour
+Target-Specific Behaviour
 =========================
 
 X86