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[PATCH rs6000: document options (PR85321)
- From: Aaron Sawdey <acsawdey at linux dot vnet dot ibm dot com>
- To: gcc-patches at gcc dot gnu dot org
- Cc: Segher Boessenkool <segher at kernel dot crashing dot org>, David Edelsohn <dje dot gcc at gmail dot com>
- Date: Tue, 10 Apr 2018 16:49:44 -0500
- Subject: [PATCH rs6000: document options (PR85321)
This updates invoke.texi to document -mblock-compare-inline-limit,
-mblock-compare-inline-loop-limit, and -mstring-compare-inline-limit.
Tested with "make pdf", ok for trunk?
2018-04-10 Aaron Sawdey <acsawdey@linux.ibm.com>
PR target/85321
* doc/invoke.texi (RS/6000 and PowerPC Options): Document options
-mblock-compare-inline-limit, -mblock-compare-inline-loop-limit,
and -mstring-compare-inline-limit.
--
Aaron Sawdey, Ph.D. acsawdey@linux.vnet.ibm.com
050-2/C113 (507) 253-7520 home: 507/263-0782
IBM Linux Technology Center - PPC Toolchain
Index: gcc/doc/invoke.texi
===================================================================
--- gcc/doc/invoke.texi (revision 259295)
+++ gcc/doc/invoke.texi (working copy)
@@ -1080,6 +1080,9 @@
-maix-struct-return -msvr4-struct-return @gol
-mabi=@var{abi-type} -msecure-plt -mbss-plt @gol
-mblock-move-inline-limit=@var{num} @gol
+-mblock-compare-inline-limit=@var{num} @gol
+-mblock-compare-inline-loop-limit=@var{num} @gol
+-mstring-compare-inline-limit=@var{num} @gol
-misel -mno-isel @gol
-misel=yes -misel=no @gol
-mpaired @gol
@@ -24142,6 +24145,31 @@
@var{num} is 32 bytes on 32-bit targets and 64 bytes on 64-bit
targets. The default value is target-specific.
+@item -mblock-compare-inline-limit=@var{num}
+@opindex mblock-compare-inline-limit
+Generate non-looping inline code for all block compares (such as calls
+to @code{memcmp} or structure compares) less than or equal to @var{num}
+bytes. If @var{num} is 0, all inline expansion (non-loop and loop) of
+block compare is disabled. The default value is target-specific.
+
+@item -mblock-compare-inline-loop-limit=@var{num}
+@opindex mblock-compare-inline-loop-limit
+Generate an inline expansion using loop code for all block compares that
+are less than or equal to @var{num} bytes, but greater than the limit
+for non-loop inline block compare expansion. If the block length is not
+constant, at most @var{num} bytes will be compared before @code{memcmp}
+is called to compare the remainder of the block. The default value is
+target-specific.
+
+@item -mstring-compare-inline-limit=@var{num}
+@opindex mstring-compare-inline-limit
+Generate at most @var{num} pairs of load instructions to compare the
+string inline. If the difference or end of string is not found at the
+end of the inline compare a call to @code{strcmp} or @code{strncmp} will
+take care of the rest of the comparison. The default is 8 pairs of
+loads, which will compare 64 bytes on a 64-bit target and 32 bytes on a
+32-bit target.
+
@item -G @var{num}
@opindex G
@cindex smaller data references (PowerPC)