diff options
| -rw-r--r-- | arch/sh/mm/Makefile_64 | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/arch/sh/mm/Makefile_64 b/arch/sh/mm/Makefile_64 index 5ff83583593..2731cf1c4e0 100644 --- a/arch/sh/mm/Makefile_64 +++ b/arch/sh/mm/Makefile_64 @@ -17,3 +17,28 @@ obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o obj-$(CONFIG_NUMA) += numa.o EXTRA_CFLAGS += -Werror + +# Special flags for fault_64.o. This puts restrictions on the number of +# caller-save registers that the compiler can target when building this file. +# This is required because the code is called from a context in entry.S where +# very few registers have been saved in the exception handler (for speed +# reasons). +# The caller save registers that have been saved and which can be used are +# r2,r3,r4,r5 : argument passing +# r15, r18 : SP and LINK +# tr0-4 : allow all caller-save TR's. The compiler seems to be able to make +# use of them, so it's probably beneficial to performance to save them +# and have them available for it. +# +# The resources not listed below are callee save, i.e. the compiler is free to +# use any of them and will spill them to the stack itself. + +CFLAGS_fault_64.o += -ffixed-r7 \ + -ffixed-r8 -ffixed-r9 -ffixed-r10 -ffixed-r11 -ffixed-r12 \ + -ffixed-r13 -ffixed-r14 -ffixed-r16 -ffixed-r17 -ffixed-r19 \ + -ffixed-r20 -ffixed-r21 -ffixed-r22 -ffixed-r23 \ + -ffixed-r24 -ffixed-r25 -ffixed-r26 -ffixed-r27 \ + -ffixed-r36 -ffixed-r37 -ffixed-r38 -ffixed-r39 -ffixed-r40 \ + -ffixed-r41 -ffixed-r42 -ffixed-r43 \ + -ffixed-r60 -ffixed-r61 -ffixed-r62 \ + -fomit-frame-pointer |