This patch adds support in the various functions that check memory offsets for the 34-bit offset with prefixed instructions on the 'future' machine.
Along with the other patches, I have done bootstraps on a little endian power8 system, and there were no regressions in the test suite. Can I check this into the trunk? 2019-10-08 Michael Meissner <meiss...@linux.ibm.com> * config/rs6000/rs6000.c (quad_address_p): Add check for prefixed addresses. (mem_operand_gpr): Add check for prefixed addresses. (mem_operand_ds_form): Add check for prefixed addresses. (rs6000_legitimate_offset_address_p): If we support prefixed addresses, check for a 34-bit offset instead of 16-bit. (rs6000_legitimate_address_p): Add check for prefixed addresses. Do not allow load/store with update if the address is prefixed. (rs6000_mode_dependent_address): If we support prefixed addresses, check for a 34-bit offset instead of 16-bit. Index: gcc/config/rs6000/rs6000.c =================================================================== --- gcc/config/rs6000/rs6000.c (revision 276713) +++ gcc/config/rs6000/rs6000.c (working copy) @@ -7250,6 +7250,13 @@ quad_address_p (rtx addr, machine_mode m if (VECTOR_MODE_P (mode) && !mode_supports_dq_form (mode)) return false; + /* Is this a valid prefixed address? If the bottom four bits of the offset + are non-zero, we could use a prefixed instruction (which does not have the + DQ-form constraint that the traditional instruction had) instead of + forcing the unaligned offset to a GPR. */ + if (address_is_prefixed (addr, mode, NON_PREFIXED_DQ)) + return true; + if (GET_CODE (addr) != PLUS) return false; @@ -7351,6 +7358,13 @@ mem_operand_gpr (rtx op, machine_mode mo && legitimate_indirect_address_p (XEXP (addr, 0), false)) return true; + /* Allow prefixed instructions if supported. If the bottom two bits of the + offset are non-zero, we could use a prefixed instruction (which does not + have the DS-form constraint that the traditional instruction had) instead + of forcing the unaligned offset to a GPR. */ + if (address_is_prefixed (addr, mode, NON_PREFIXED_DS)) + return true; + /* Don't allow non-offsettable addresses. See PRs 83969 and 84279. */ if (!rs6000_offsettable_memref_p (op, mode, false)) return false; @@ -7385,6 +7399,13 @@ mem_operand_ds_form (rtx op, machine_mod int extra; rtx addr = XEXP (op, 0); + /* Allow prefixed instructions if supported. If the bottom two bits of the + offset are non-zero, we could use a prefixed instruction (which does not + have the DS-form constraint that the traditional instruction had) instead + of forcing the unaligned offset to a GPR. */ + if (address_is_prefixed (addr, mode, NON_PREFIXED_DS)) + return true; + if (!offsettable_address_p (false, mode, addr)) return false; @@ -7754,7 +7775,10 @@ rs6000_legitimate_offset_address_p (mach break; } - return SIGNED_16BIT_OFFSET_EXTRA_P (offset, extra); + if (TARGET_PREFIXED_ADDR) + return SIGNED_34BIT_OFFSET_EXTRA_P (offset, extra); + else + return SIGNED_16BIT_OFFSET_EXTRA_P (offset, extra); } bool @@ -8651,6 +8675,11 @@ rs6000_legitimate_address_p (machine_mod && mode_supports_pre_incdec_p (mode) && legitimate_indirect_address_p (XEXP (x, 0), reg_ok_strict)) return 1; + + /* Handle prefixed addresses (PC-relative or 34-bit offset). */ + if (address_is_prefixed (x, mode, NON_PREFIXED_DEFAULT)) + return 1; + /* Handle restricted vector d-form offsets in ISA 3.0. */ if (quad_offset_p) { @@ -8709,7 +8738,11 @@ rs6000_legitimate_address_p (machine_mod || (!avoiding_indexed_address_p (mode) && legitimate_indexed_address_p (XEXP (x, 1), reg_ok_strict))) && rtx_equal_p (XEXP (XEXP (x, 1), 0), XEXP (x, 0))) - return 1; + { + /* There is no prefixed version of the load/store with update. */ + rtx addr = XEXP (x, 1); + return !address_is_prefixed (addr, mode, NON_PREFIXED_DEFAULT); + } if (reg_offset_p && !quad_offset_p && legitimate_lo_sum_address_p (mode, x, reg_ok_strict)) return 1; @@ -8773,7 +8806,10 @@ rs6000_mode_dependent_address (const_rtx { HOST_WIDE_INT val = INTVAL (XEXP (addr, 1)); HOST_WIDE_INT extra = TARGET_POWERPC64 ? 8 : 12; - return !SIGNED_16BIT_OFFSET_EXTRA_P (val, extra); + if (TARGET_PREFIXED_ADDR) + return !SIGNED_34BIT_OFFSET_EXTRA_P (val, extra); + else + return !SIGNED_16BIT_OFFSET_EXTRA_P (val, extra); } break; -- Michael Meissner, IBM IBM, M/S 2506R, 550 King Street, Littleton, MA 01460-6245, USA email: meiss...@linux.ibm.com, phone: +1 (978) 899-4797