https://gcc.gnu.org/g:c781da2c10641a651019f8fe77f57ccdbc49f024
commit r15-7892-gc781da2c10641a651019f8fe77f57ccdbc49f024
Author: Sandra Loosemore <sloosem...@baylibre.com>
Date: Fri Mar 7 17:08:30 2025 +0000
x86: Improve documentation for -msse4 [PR116708]
gcc/ChangeLog
PR target/116708
* doc/invoke.texi (x86 Options): Clarify how -msse4 and -mno-sse4
interact with other SSE options.
Diff:
---
gcc/doc/invoke.texi | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index d95580220731..c61f35140702 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -35924,6 +35924,11 @@ These extensions are also available as built-in
functions: see
@ref{x86 Built-in Functions}, for details of the functions enabled and
disabled by these switches.
+Note that @option{-msse4} enables both SSE4.1 and SSE4.2 support,
+while @option{-mno-sse4} turns off those features; neither form of the
+option affects SSE4A support, controlled separately by
+@option{-msse4a}.
+
To generate SSE/SSE2 instructions automatically from floating-point
code (as opposed to 387 instructions), see @option{-mfpmath=sse}.
