The documentation of both options is still inconsistent, in both the
trunk and the gcc-8 branch.
The following is my suggestion to clear this up (and move
-floop-unroll-and-jam close to -floop-interchange.
ChangeLog:
2018-05-17 Toon Moene
* doc/invoke.texi: Move -floop-unroll-and-jam documentation
directly after that of -floop-interchange. Indicate that both
options are enabled by default when specifying -O3.
OK for trunk and gcc-8 ?
--
Toon Moene - e-mail: t...@moene.org - phone: +31 346 214290
Saturnushof 14, 3738 XG Maartensdijk, The Netherlands
At home: http://moene.org/~toon/; weather: http://moene.org/~hirlam/
Progress of GNU Fortran: http://gcc.gnu.org/wiki/GFortran#news
Index: invoke.texi
===
--- invoke.texi (revision 260287)
+++ invoke.texi (working copy)
@@ -8866,7 +8866,14 @@
for (int j = 0; j < N; j++)
c[i][j] = c[i][j] + a[i][k]*b[k][j];
@end smallexample
+This flag is enabled by default at @option{-O3}.
+@item -floop-unroll-and-jam
+@opindex floop-unroll-and-jam
+Apply unroll and jam transformations on feasible loops. In a loop
+nest this unrolls the outer loop by some factor and fuses the resulting
+multiple inner loops. This flag is enabled by default at @option{-O3}.
+
@item -ftree-loop-im
@opindex ftree-loop-im
Perform loop invariant motion on trees. This pass moves only invariants that
@@ -10038,12 +10045,6 @@
Move branches with loop invariant conditions out of the loop, with duplicates
of the loop on both branches (modified according to result of the condition).
-@item -floop-unroll-and-jam
-@opindex floop-unroll-and-jam
-Apply unroll and jam transformations on feasible loops. In a loop
-nest this unrolls the outer loop by some factor and fuses the resulting
-multiple inner loops.
-
@item -ffunction-sections
@itemx -fdata-sections
@opindex ffunction-sections