doc: Update -falign-functions/-falign-loops/-falign-jumps

Change -falign-functions=N to

    Align the start of functions to the next power-of-two greater than
    or equal to N.

Add

    If '-falign-labels' is greater than this value, then its value is
    used instead.

to -falign-loops=N and -falign-jumps=N.

	PR driver/94381
	* doc/invoke.texi: Update -falign-functions, -falign-loops and
	-falign-jumps documentation.

gcc/ChangeLog

+2020-03-29  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR driver/94381
+	* doc/invoke.texi: Update -falign-functions, -falign-loops and
+	-falign-jumps documentation.
+
 2020-03-29  Martin Liska  <mliska@suse.cz>
 
 	PR ipa/94363

gcc/doc/invoke.texi

@@ -10939,9 +10939,9 @@ The @option{-fstrict-aliasing} option is enabled at levels
 @itemx -falign-functions=@var{n}:@var{m}:@var{n2}
 @itemx -falign-functions=@var{n}:@var{m}:@var{n2}:@var{m2}
 @opindex falign-functions
-Align the start of functions to the next power-of-two greater than
-@var{n}, skipping up to @var{m}-1 bytes.  This ensures that at least
-the first @var{m} bytes of the function can be fetched by the CPU
+Align the start of functions to the next power-of-two greater than or
+equal to @var{n}, skipping up to @var{m}-1 bytes.  This ensures that at
+least the first @var{m} bytes of the function can be fetched by the CPU
 without crossing an @var{n}-byte alignment boundary.
 
 If @var{m} is not specified, it defaults to @var{n}.
@@ -11007,6 +11007,9 @@ Align loops to a power-of-two boundary.  If the loops are executed
 many times, this makes up for any execution of the dummy padding
 instructions.
 
+If @option{-falign-labels} is greater than this value, then its value
+is used instead.
+
 Parameters of this option are analogous to the @option{-falign-functions} option.
 @option{-fno-align-loops} and @option{-falign-loops=1} are
 equivalent and mean that loops are not aligned.
@@ -11026,6 +11029,9 @@ Align branch targets to a power-of-two boundary, for branch targets
 where the targets can only be reached by jumping.  In this case,
 no dummy operations need be executed.
 
+If @option{-falign-labels} is greater than this value, then its value
+is used instead.
+
 Parameters of this option are analogous to the @option{-falign-functions} option.
 @option{-fno-align-jumps} and @option{-falign-jumps=1} are
 equivalent and mean that loops are not aligned.