Updating register classes so that the narrowest class for the SRP register is now a singleton class, instead of having other register members without means to move to/from SRP cheaper than memory, matching the documentation update. Also fixing the buglet of not fixing the condition-code-register, ehm. (Not that there could be moves for anything but CCmode to or from it, which is useless anyway for a CC0 port.) All-in-all, together with the ira-costs.c patch just committed, unbreaking build for cris-elf with results at patched r174780 similar to those of r174114 before the breakage, just adding a libstdc++ SEGV for 20_util/is_nothrow_copy_assignable/value.cc; a regression which seems unrelated anyway -save-temps makes it go away. Committed.
PR rtl-optimization/49154 * config/cris/cris.h (FIXED_REGISTERS): Include CRIS_CC0_REGNUM. (enum reg_class): Add SRP_REGS and MOF_SRP_REGS. (REG_CLASS_NAMES, REG_CLASS_CONTENTS, REGNO_REG_CLASS) (PREFERRED_RELOAD_CLASS, SECONDARY_RELOAD_CLASS): Adjust to fit. * config/cris/cris.h (cris_register_move_cost): Remove !TARGET_V32 code. Tweak comments. diff --git gcc/config/cris/cris.c gcc/config/cris/cris.c index 110e985..159b31b 100644 --- gcc/config/cris/cris.c +++ gcc/config/cris/cris.c @@ -1360,24 +1360,11 @@ static int cris_register_move_cost (enum machine_mode mode ATTRIBUTE_UNUSED, reg_class_t from, reg_class_t to) { - if (!TARGET_V32) - { - /* Pretend that classes that we don't support are ALL_REGS, so - we give them the highest cost. */ - if (from != SPECIAL_REGS && from != MOF_REGS - && from != GENERAL_REGS && from != GENNONACR_REGS) - from = ALL_REGS; - - if (to != SPECIAL_REGS && to != MOF_REGS - && to != GENERAL_REGS && to != GENNONACR_REGS) - to = ALL_REGS; - } - /* Can't move to and from a SPECIAL_REGS register, so we have to say their move cost within that class is higher. How about 7? That's 3 for a move to a GENERAL_REGS register, 3 for the move from the GENERAL_REGS register, and 1 for the increased register pressure. - Also, it's higher than the memory move cost, which is in order. + Also, it's higher than the memory move cost, as it should. We also do this for ALL_REGS, since we don't want that class to be preferred (even to memory) at all where GENERAL_REGS doesn't fit. Whenever it's about to be used, it's for SPECIAL_REGS. If we don't @@ -1386,13 +1373,15 @@ cris_register_move_cost (enum machine_mode mode ATTRIBUTE_UNUSED, GENERAL_REGS left to allocate. This is because the fall-back when the most preferred register class isn't available, isn't the next (or next good) wider register class, but the *most widest* register - class. */ + class. FIXME: pre-IRA comment, perhaps obsolete now. */ if ((reg_classes_intersect_p (from, SPECIAL_REGS) && reg_classes_intersect_p (to, SPECIAL_REGS)) || from == ALL_REGS || to == ALL_REGS) return 7; + /* Make moves to/from SPECIAL_REGS slightly more expensive, as we + generally prefer GENERAL_REGS. */ if (reg_classes_intersect_p (from, SPECIAL_REGS) || reg_classes_intersect_p (to, SPECIAL_REGS)) return 3; diff --git gcc/config/cris/cris.h gcc/config/cris/cris.h index 57bdd46..872165e 100644 --- gcc/config/cris/cris.h +++ gcc/config/cris/cris.h @@ -418,7 +418,7 @@ extern int cris_cpu_version; registers are fixed at the moment. The faked argument pointer register is fixed too. */ #define FIXED_REGISTERS \ - {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0} + {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 1} /* Register r9 is used for structure-address, r10-r13 for parameters, r10- for return values. */ @@ -488,17 +488,17 @@ extern int cris_cpu_version; /* Node: Register Classes */ -/* FIXME: A separate class for the return register would make sense. - - We need a separate register class to handle register allocation for +/* We need a separate register class to handle register allocation for ACR, since it can't be used for post-increment. It's not obvious, but having subunions of all movable-between - register classes does really help register allocation. */ + register classes does really help register allocation (pre-IRA + comment). */ enum reg_class { NO_REGS, - ACR_REGS, MOF_REGS, CC0_REGS, SPECIAL_REGS, + ACR_REGS, MOF_REGS, SRP_REGS, CC0_REGS, + MOF_SRP_REGS, SPECIAL_REGS, SPEC_ACR_REGS, GENNONACR_REGS, SPEC_GENNONACR_REGS, GENERAL_REGS, ALL_REGS, @@ -509,7 +509,8 @@ enum reg_class #define REG_CLASS_NAMES \ {"NO_REGS", \ - "ACR_REGS", "MOF_REGS", "CC0_REGS", "SPECIAL_REGS", \ + "ACR_REGS", "MOF_REGS", "SRP_REGS", "CC0_REGS", \ + "MOF_SRP_REGS", "SPECIAL_REGS", \ "SPEC_ACR_REGS", "GENNONACR_REGS", "SPEC_GENNONACR_REGS", \ "GENERAL_REGS", "ALL_REGS"} @@ -522,7 +523,10 @@ enum reg_class {0}, \ {1 << CRIS_ACR_REGNUM}, \ {1 << CRIS_MOF_REGNUM}, \ + {1 << CRIS_SRP_REGNUM}, \ {1 << CRIS_CC0_REGNUM}, \ + {(1 << CRIS_MOF_REGNUM) \ + | (1 << CRIS_SRP_REGNUM)}, \ {CRIS_SPECIAL_REGS_CONTENTS}, \ {CRIS_SPECIAL_REGS_CONTENTS \ | (1 << CRIS_ACR_REGNUM)}, \ @@ -539,8 +543,8 @@ enum reg_class #define REGNO_REG_CLASS(REGNO) \ ((REGNO) == CRIS_ACR_REGNUM ? ACR_REGS : \ (REGNO) == CRIS_MOF_REGNUM ? MOF_REGS : \ + (REGNO) == CRIS_SRP_REGNUM ? SRP_REGS : \ (REGNO) == CRIS_CC0_REGNUM ? CC0_REGS : \ - (REGNO) == CRIS_SRP_REGNUM ? SPECIAL_REGS : \ GENERAL_REGS) #define BASE_REG_CLASS GENERAL_REGS @@ -590,6 +594,7 @@ enum reg_class #define PREFERRED_RELOAD_CLASS(X, CLASS) \ ((CLASS) != ACR_REGS \ && (CLASS) != MOF_REGS \ + && (CLASS) != SRP_REGS \ && (CLASS) != CC0_REGS \ && (CLASS) != SPECIAL_REGS \ ? GENERAL_REGS : (CLASS)) @@ -601,7 +606,7 @@ enum reg_class the effect that any X that isn't a special-register is treated as a non-empty intersection with GENERAL_REGS. */ #define SECONDARY_RELOAD_CLASS(CLASS, MODE, X) \ - ((((CLASS) == SPECIAL_REGS || (CLASS) == MOF_REGS) \ + ((reg_class_subset_p (CLASS, SPECIAL_REGS) \ && ((GET_MODE_SIZE (MODE) < 4 && MEM_P (X)) \ || !reg_classes_intersect_p (REGNO_REG_CLASS (true_regnum (X)), \ GENERAL_REGS))) \ brgds, H-P