Remove unused option that gcc ignored

[MaskRay]

Can we just delete the options?

The misspelled options were added in rC214906 to work around https://clang.debian.net/status.php?version=3.4.2&key=UNKNOWN_ARG . Actually the -ftree* options were not used. Apparently our option names has been wrong for 5 years and nobody complains.

[Jim]

It should be kept for compatibility. These three options may be used in other projects compiled by gcc.
Clang should ignore it.
https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html

[MaskRay]

These three options may be used in other projects compiled by gcc.

We can add them on demand. I don't see a rationale to add them preemptively.

[Jim]

Address the comment. Delete the options.

[Jim]

ping?

[efriedma]

LGTM

clang/include/clang/Driver/Options.td

defm single_precision_constant : BooleanFFlag<"single-precision-constant">,
     Group<clang_ignored_gcc_optimization_f_Group>;
 defm spec_constr_count : BooleanFFlag<"spec-constr-count">, Group<clang_ignored_f_Group>;
 defm stack_check : BooleanFFlag<"stack-check">, Group<clang_ignored_f_Group>;
 defm strength_reduce :
     BooleanFFlag<"strength-reduce">, Group<clang_ignored_gcc_optimization_f_Group>;
 defm tls_model : BooleanFFlag<"tls-model">, Group<clang_ignored_f_Group>;
 defm tracer : BooleanFFlag<"tracer">, Group<clang_ignored_gcc_optimization_f_Group>;
 defm tree_dce : BooleanFFlag<"tree-dce">, Group<clang_ignored_gcc_optimization_f_Group>;
-defm tree_loop_im : BooleanFFlag<"tree_loop_im">,  Group<clang_ignored_gcc_optimization_f_Group>;
-defm tree_loop_ivcanon : BooleanFFlag<"tree_loop_ivcanon">,  Group<clang_ignored_gcc_optimization_f_Group>;
-defm tree_loop_linear : BooleanFFlag<"tree_loop_linear">,  Group<clang_ignored_gcc_optimization_f_Group>;
 defm tree_salias : BooleanFFlag<"tree-salias">, Group<clang_ignored_f_Group>;
 defm tree_ter : BooleanFFlag<"tree-ter">, Group<clang_ignored_gcc_optimization_f_Group>;
 defm tree_vectorizer_verbose : BooleanFFlag<"tree-vectorizer-verbose">, Group<clang_ignored_f_Group>;
 defm tree_vrp : BooleanFFlag<"tree-vrp">, Group<clang_ignored_gcc_optimization_f_Group>;
 defm unroll_all_loops : BooleanFFlag<"unroll-all-loops">, Group<clang_ignored_gcc_optimization_f_Group>;
 defm unsafe_loop_optimizations : BooleanFFlag<"unsafe-loop-optimizations">,
     Group<clang_ignored_gcc_optimization_f_Group>;
 defm unswitch_loops : BooleanFFlag<"unswitch-loops">, Group<clang_ignored_gcc_optimization_f_Group>;

clang/test/Driver/clang_f_opts.c

 // RUN:     -fipa-cp                                                          \
 // RUN:     -finline-functions-called-once                                    \
 // RUN:     -fmodulo-sched                                                    \
 // RUN:     -fmodulo-sched-allow-regmoves                                     \
 // RUN:     -fpeel-loops                                                      \
 // RUN:     -frename-registers                                                \
 // RUN:     -fschedule-insns2                                                 \
 // RUN:     -fsingle-precision-constant                                       \
-// RUN:     -ftree_loop_im                                                    \
-// RUN:     -ftree_loop_ivcanon                                               \
-// RUN:     -ftree_loop_linear                                                \
 // RUN:     -funsafe-loop-optimizations                                       \
 // RUN:     -fuse-linker-plugin                                               \
 // RUN:     -fvect-cost-model                                                 \
 // RUN:     -fvariable-expansion-in-unroller                                  \
 // RUN:     -fweb                                                             \
 // RUN:     -fwhole-program                                                   \
 // RUN:     -fno-tree-dce -ftree-dce                                          \
 // RUN:     -fno-tree-ter -ftree-ter                                          \

 // CHECK-WARNING-DAG: optimization flag '-fipa-cp' is not supported
 // CHECK-WARNING-DAG: optimization flag '-finline-functions-called-once' is not supported
 // CHECK-WARNING-DAG: optimization flag '-fmodulo-sched' is not supported
 // CHECK-WARNING-DAG: optimization flag '-fmodulo-sched-allow-regmoves' is not supported
 // CHECK-WARNING-DAG: optimization flag '-fpeel-loops' is not supported
 // CHECK-WARNING-DAG: optimization flag '-frename-registers' is not supported
 // CHECK-WARNING-DAG: optimization flag '-fschedule-insns2' is not supported
 // CHECK-WARNING-DAG: optimization flag '-fsingle-precision-constant' is not supported
-// CHECK-WARNING-DAG: optimization flag '-ftree_loop_im' is not supported
-// CHECK-WARNING-DAG: optimization flag '-ftree_loop_ivcanon' is not supported
-// CHECK-WARNING-DAG: optimization flag '-ftree_loop_linear' is not supported
 // CHECK-WARNING-DAG: optimization flag '-funsafe-loop-optimizations' is not supported
 // CHECK-WARNING-DAG: optimization flag '-fuse-linker-plugin' is not supported
 // CHECK-WARNING-DAG: optimization flag '-fvect-cost-model' is not supported
 // CHECK-WARNING-DAG: optimization flag '-fvariable-expansion-in-unroller' is not supported
 // CHECK-WARNING-DAG: optimization flag '-fweb' is not supported
 // CHECK-WARNING-DAG: optimization flag '-fwhole-program' is not supported
 // CHECK-WARNING-DAG: optimization flag '-fcaller-saves' is not supported
 // CHECK-WARNING-DAG: optimization flag '-freorder-blocks' is not supported