Commit 5be645a introduces the support of --with-cpu. The current
implementation specifies an `-march` option based on the default cpu
value. This behavior is not consistent with how the `-mcpu` option
works, however, as the `-mcpu` option involves both `-march` and
`-mtune`. Only setting the `-march` value can be confusing for users,
who may expect the --with-cpu option to act the same way as an explicit
`-mcpu` option.
If it is some design choice, though, I would be glad to know.
Thanks,
Bohan
gcc/ChangeLog:
* config/riscv/riscv.h (riscv_arch_help):
(OPTION_DEFAULT_SPECS): Specify -mcpu instead of -march when
--with-cpu is used.
---
gcc/config/riscv/riscv.h | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/gcc/config/riscv/riscv.h b/gcc/config/riscv/riscv.h
index 195012f216b..6ff3e09ecc7 100644
--- a/gcc/config/riscv/riscv.h
+++ b/gcc/config/riscv/riscv.h
@@ -60,7 +60,8 @@ extern const char *riscv_arch_help (int argc, const char
**argv);
{ "riscv_arch_help", riscv_arch_help },
/* Support for a compile-time default CPU, et cetera. The rules are:
- --with-arch and --with-cpu are ignored if -march or -mcpu is specified.
+ --with-cpu is ignored if -mcpu is specified.
+ --with-arch is ignored if -march or -mcpu is specified.
--with-abi is ignored if -mabi is specified.
--with-tune is ignored if -mtune or -mcpu is specified.
--with-isa-spec is ignored if -misa-spec is specified.
@@ -68,10 +69,10 @@ extern const char *riscv_arch_help (int argc, const char
**argv);
Uses default values if -mcpu doesn't have a valid option. */
#define OPTION_DEFAULT_SPECS \
+ {"cpu", "%{!mcpu=*:-mcpu=%(VALUE)}" }, \
{"tune", "%{!mtune=*:" \
" %{!mcpu=*:-mtune=%(VALUE)}" \
" %{mcpu=*:-mtune=%:riscv_default_mtune(%* %(VALUE))}}" }, \
- {"cpu", "%{!march=*:%{!mcpu=*:%:riscv_expand_arch_from_cpu(%(VALUE))}}" }, \
{"arch", "%{!march=*|march=unset:" \
" %{!mcpu=*:-march=%(VALUE)}" \
" %{mcpu=*:%:riscv_expand_arch_from_cpu(%* %(VALUE))}}" }, \
--
2.46.0
