From: Hau Hsu <[email protected]>
Sometimes we want to use default cmodel other than medlow. Add a GCC
configure option for that.
gcc/ChangeLog:
* config.gcc (riscv*-*-*): Add support for --with-cmodel configure
option.
(all_defaults): Add cmodel.
* config/riscv/riscv.h (TARGET_DEFAULT_CMODEL): Remove.
* doc/install.texi: Document --with-cmodel configure option.
* doc/invoke.texi (-mcmodel): Mention --with-cmodel configure option.
Co-authored-by: Kito Cheng <[email protected]>
---
v3:
I've confirmed the v2 of this patch will break all other target's build,
and I've fixed the issue in this version, tested on AArch64, passed 3 stage
bootstrap.
Also clean up this patch to remove unnecessary changes.
Will commit after CI pass.
---
gcc/config.gcc | 23 +++++++++++++++++++++--
gcc/config/riscv/riscv.h | 2 --
gcc/doc/install.texi | 4 ++++
gcc/doc/invoke.texi | 6 ++++--
4 files changed, 29 insertions(+), 6 deletions(-)
diff --git a/gcc/config.gcc b/gcc/config.gcc
index afa78453197..f4ae14c6db2 100644
--- a/gcc/config.gcc
+++ b/gcc/config.gcc
@@ -4711,7 +4711,7 @@ case "${target}" in
;;
riscv*-*-*)
- supported_defaults="abi arch tune riscv_attribute isa_spec tls"
+ supported_defaults="abi arch tune riscv_attribute isa_spec tls
cmodel"
case "${target}" in
riscv-* | riscv32*) xlen=32 ;;
@@ -4867,6 +4867,25 @@ case "${target}" in
exit 1
esac
fi
+
+ # Handle --with-cmodel.
+ # Make sure --with-cmodel is valid. If it was not specified,
+ # use medlow as the default value.
+ case "${with_cmodel}" in
+ "" | medlow)
+ tm_defines="${tm_defines}
TARGET_DEFAULT_CMODEL=CM_MEDLOW"
+ ;;
+ medany)
+ tm_defines="${tm_defines}
TARGET_DEFAULT_CMODEL=CM_MEDANY"
+ ;;
+ large)
+ tm_defines="${tm_defines}
TARGET_DEFAULT_CMODEL=CM_LARGE"
+ ;;
+ *)
+ echo "invalid option for --with-cmodel:
'${with_cmodel}', available values are 'medlow' 'medany' 'large'" 1>&2
+ exit 1
+ ;;
+ esac
;;
mips*-*-*)
@@ -6046,7 +6065,7 @@ case ${target} in
esac
t=
-all_defaults="abi cpu cpu_32 cpu_64 arch arch_32 arch_64 tune tune_32 tune_64
schedule float mode fpu nan fp_32 odd_spreg_32 divide llsc mips-plt synci tls
lxc1-sxc1 madd4 isa_spec compact-branches msa"
+all_defaults="abi cpu cpu_32 cpu_64 arch arch_32 arch_64 tune tune_32 tune_64
schedule float mode fpu nan fp_32 odd_spreg_32 divide llsc mips-plt synci tls
lxc1-sxc1 madd4 isa_spec compact-branches msa cmodel"
for option in $all_defaults
do
eval "val=\$with_"`echo $option | sed s/-/_/g`
diff --git a/gcc/config/riscv/riscv.h b/gcc/config/riscv/riscv.h
index 8a8b08b6b51..09de74667a9 100644
--- a/gcc/config/riscv/riscv.h
+++ b/gcc/config/riscv/riscv.h
@@ -119,8 +119,6 @@ ASM_MISA_SPEC
"%{march=*:%:riscv_expand_arch(%*)} " \
"%{!march=*:%{mcpu=*:%:riscv_expand_arch_from_cpu(%*)}} "
-#define TARGET_DEFAULT_CMODEL CM_MEDLOW
-
#define LOCAL_LABEL_PREFIX "."
#define USER_LABEL_PREFIX ""
diff --git a/gcc/doc/install.texi b/gcc/doc/install.texi
index 97d9aaffa69..4107697f10c 100644
--- a/gcc/doc/install.texi
+++ b/gcc/doc/install.texi
@@ -1537,6 +1537,10 @@ Use big endian by default. Provide a multilib for
little endian.
Use little endian by default. Provide a multilib for big endian.
@end table
+@item --with-cmodel=@var{cmodel}
+Specify what code model to use by default.
+Currently only implemented for riscv*-*-*.
+
@item --enable-threads
Specify that the target
supports threads. This affects the Objective-C compiler and runtime
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index d2409a41d50..0107da32b64 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -31092,8 +31092,10 @@ element-misaligned vector memory access.
@item -mcmodel=medlow
Generate code for the medium-low code model. The program and its statically
defined symbols must lie within a single 2 GiB address range and must lie
-between absolute addresses @minus{}2 GiB and +2 GiB. Programs can be
-statically or dynamically linked. This is the default code model.
+between absolute addresses @minus{}2 GiB and +2 GiB. Programs can be statically
+or dynamically linked. This is the default code model unless GCC has been
+configured with @option{--with-cmodel=} specifying a different default code
+model.
@opindex mcmodel=medany
@item -mcmodel=medany
--
2.34.1
