This patch fixes an issue Aaron Sawdey with vector extracts. The vector address adjust functions have a single base register temporary. However for PC-relative addresses where the vector element is not constant, it logically will need two temporary registers, one to load up the PC-relative address, and the other to hold the offset of the vector element being extracted.
If a vector has a prefixed address and the vector element being extracted is not constant, this code will load the vector into a register, and then do the variable extract from that register, insted of just loading the scalar value up. 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 (rs6000_adjust_vec_address): Add support for optimizing PC-relative addresses with a constant element number. Assert that PC-relative vectors do not have variable element numbers. Add support for prefixed addresses with 34-bit offsets. * config/rs6000/vsx.md (vsx_extract_<mode>_var, VSX_D iterator): Do not allow combining prefixed memory with a variable vector extract. (vsx_extract_v4sf_var): Do not allow combining prefixed memory with a variable vector extract. (vsx_extract_<mode>_var, VSX_EXTRACT_I iterator): Do not allow combining prefixed memory with a variable vector extract. (vsx_extract_<mode>_<VS_scalar>mode_var): Do not allow combining prefixed memory with a variable vector extract. Index: gcc/config/rs6000/rs6000.c =================================================================== --- gcc/config/rs6000/rs6000.c (revision 276719) +++ gcc/config/rs6000/rs6000.c (working copy) @@ -6701,6 +6701,7 @@ rs6000_adjust_vec_address (rtx scalar_re rtx element_offset; rtx new_addr; bool valid_addr_p; + bool pcrel_p = pcrel_local_address (addr, Pmode); /* Vector addresses should not have PRE_INC, PRE_DEC, or PRE_MODIFY. */ gcc_assert (GET_RTX_CLASS (GET_CODE (addr)) != RTX_AUTOINC); @@ -6738,6 +6739,38 @@ rs6000_adjust_vec_address (rtx scalar_re else if (REG_P (addr) || SUBREG_P (addr)) new_addr = gen_rtx_PLUS (Pmode, addr, element_offset); + /* Optimize PC-relative addresses with a constant offset. */ + else if (pcrel_p && CONST_INT_P (element_offset)) + { + rtx addr2 = addr; + HOST_WIDE_INT offset = INTVAL (element_offset); + + if (GET_CODE (addr2) == CONST) + addr2 = XEXP (addr2, 0); + + if (GET_CODE (addr2) == PLUS) + { + offset += INTVAL (XEXP (addr2, 1)); + addr2 = XEXP (addr2, 0); + } + + gcc_assert (SIGNED_34BIT_OFFSET_P (offset)); + if (offset) + { + addr2 = gen_rtx_PLUS (Pmode, addr2, GEN_INT (offset)); + new_addr = gen_rtx_CONST (Pmode, addr2); + } + else + new_addr = addr2; + } + + /* With only one temporary base register, we can't support a PC-relative + address added to a variable offset. This is because the PADDI instruction + requires RA to be 0 when doing a PC-relative add (i.e. no register to add + to). */ + else if (pcrel_p) + gcc_unreachable (); + /* Optimize D-FORM addresses with constant offset with a constant element, to include the element offset in the address directly. */ else if (GET_CODE (addr) == PLUS) @@ -6752,8 +6785,11 @@ rs6000_adjust_vec_address (rtx scalar_re HOST_WIDE_INT offset = INTVAL (op1) + INTVAL (element_offset); rtx offset_rtx = GEN_INT (offset); - if (IN_RANGE (offset, -32768, 32767) - && (scalar_size < 8 || (offset & 0x3) == 0)) + if (TARGET_PREFIXED_ADDR && SIGNED_34BIT_OFFSET_P (offset)) + new_addr = gen_rtx_PLUS (Pmode, op0, offset_rtx); + + else if (SIGNED_16BIT_OFFSET_P (offset) + && (scalar_size < 8 || (offset & 0x3) == 0)) new_addr = gen_rtx_PLUS (Pmode, op0, offset_rtx); else { @@ -6801,11 +6837,11 @@ rs6000_adjust_vec_address (rtx scalar_re new_addr = gen_rtx_PLUS (Pmode, base_tmp, element_offset); } - /* If we have a PLUS, we need to see whether the particular register class - allows for D-FORM or X-FORM addressing. */ - if (GET_CODE (new_addr) == PLUS) + /* If we have a PLUS or a PC-relative address without the PLUS, we need to + see whether the particular register class allows for D-FORM or X-FORM + addressing. */ + if (GET_CODE (new_addr) == PLUS || pcrel_p) { - rtx op1 = XEXP (new_addr, 1); addr_mask_type addr_mask; unsigned int scalar_regno = reg_or_subregno (scalar_reg); @@ -6822,10 +6858,16 @@ rs6000_adjust_vec_address (rtx scalar_re else gcc_unreachable (); - if (REG_P (op1) || SUBREG_P (op1)) - valid_addr_p = (addr_mask & RELOAD_REG_INDEXED) != 0; - else + if (pcrel_p) valid_addr_p = (addr_mask & RELOAD_REG_OFFSET) != 0; + else + { + rtx op1 = XEXP (new_addr, 1); + if (REG_P (op1) || SUBREG_P (op1)) + valid_addr_p = (addr_mask & RELOAD_REG_INDEXED) != 0; + else + valid_addr_p = (addr_mask & RELOAD_REG_OFFSET) != 0; + } } else if (REG_P (new_addr) || SUBREG_P (new_addr)) Index: gcc/config/rs6000/vsx.md =================================================================== --- gcc/config/rs6000/vsx.md (revision 276720) +++ gcc/config/rs6000/vsx.md (working copy) @@ -3239,9 +3239,10 @@ (define_insn "vsx_vslo_<mode>" ;; Variable V2DI/V2DF extract (define_insn_and_split "vsx_extract_<mode>_var" [(set (match_operand:<VS_scalar> 0 "gpc_reg_operand" "=v,wa,r") - (unspec:<VS_scalar> [(match_operand:VSX_D 1 "input_operand" "v,m,m") - (match_operand:DI 2 "gpc_reg_operand" "r,r,r")] - UNSPEC_VSX_EXTRACT)) + (unspec:<VS_scalar> + [(match_operand:VSX_D 1 "reg_or_non_prefixed_memory" "v,em,em") + (match_operand:DI 2 "gpc_reg_operand" "r,r,r")] + UNSPEC_VSX_EXTRACT)) (clobber (match_scratch:DI 3 "=r,&b,&b")) (clobber (match_scratch:V2DI 4 "=&v,X,X"))] "VECTOR_MEM_VSX_P (<MODE>mode) && TARGET_DIRECT_MOVE_64BIT" @@ -3309,9 +3310,10 @@ (define_insn_and_split "*vsx_extract_v4s ;; Variable V4SF extract (define_insn_and_split "vsx_extract_v4sf_var" [(set (match_operand:SF 0 "gpc_reg_operand" "=wa,wa,?r") - (unspec:SF [(match_operand:V4SF 1 "input_operand" "v,m,m") - (match_operand:DI 2 "gpc_reg_operand" "r,r,r")] - UNSPEC_VSX_EXTRACT)) + (unspec:SF + [(match_operand:V4SF 1 "reg_or_non_prefixed_memory" "v,em,em") + (match_operand:DI 2 "gpc_reg_operand" "r,r,r")] + UNSPEC_VSX_EXTRACT)) (clobber (match_scratch:DI 3 "=r,&b,&b")) (clobber (match_scratch:V2DI 4 "=&v,X,X"))] "VECTOR_MEM_VSX_P (V4SFmode) && TARGET_DIRECT_MOVE_64BIT" @@ -3672,7 +3674,7 @@ (define_insn_and_split "*vsx_extract_<mo (define_insn_and_split "vsx_extract_<mode>_var" [(set (match_operand:<VS_scalar> 0 "gpc_reg_operand" "=r,r,r") (unspec:<VS_scalar> - [(match_operand:VSX_EXTRACT_I 1 "input_operand" "v,v,m") + [(match_operand:VSX_EXTRACT_I 1 "reg_or_non_prefixed_memory" "v,v,em") (match_operand:DI 2 "gpc_reg_operand" "r,r,r")] UNSPEC_VSX_EXTRACT)) (clobber (match_scratch:DI 3 "=r,r,&b")) @@ -3692,7 +3694,7 @@ (define_insn_and_split "*vsx_extract_<mo [(set (match_operand:<VS_scalar> 0 "gpc_reg_operand" "=r,r,r") (zero_extend:<VS_scalar> (unspec:<VSX_EXTRACT_I:VS_scalar> - [(match_operand:VSX_EXTRACT_I 1 "input_operand" "v,v,m") + [(match_operand:VSX_EXTRACT_I 1 "reg_or_non_prefixed_memory" "v,v,em") (match_operand:DI 2 "gpc_reg_operand" "r,r,r")] UNSPEC_VSX_EXTRACT))) (clobber (match_scratch:DI 3 "=r,r,&b")) -- 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