From: Marek Michalkiewicz Date: Sun, 13 Mar 2005 21:49:45 +0000 (+0100) Subject: re PR target/20288 (AVR assignment of a value through a 16 bit pointer generates... X-Git-Tag: releases/gcc-3.4.4~159 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=10cac4fb1d8cf89818e7fedc2a5127c9984a2daf;p=thirdparty%2Fgcc.git re PR target/20288 (AVR assignment of a value through a 16 bit pointer generates out of order code) PR target/20288 * config/avr/avr.c (print_operand): Add 'p' and 'r'. (out_movhi_r_mr): Read low byte of volatile MEM first. (out_movhi_mr_r): Write high byte of volatile MEM first. From-SVN: r96394 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 9a50f151976d..8a1c6423b23b 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2005-03-13 Marek Michalkiewicz + + PR target/20288 + * config/avr/avr.c (print_operand): Add 'p' and 'r'. + (out_movhi_r_mr): Read low byte of volatile MEM first. + (out_movhi_mr_r): Write high byte of volatile MEM first. + 2005-03-10 Aldy Hernandez * doc/invoke.texi: Add 8540 to list of cpus in rs6000 cpu section. diff --git a/gcc/config/avr/avr.c b/gcc/config/avr/avr.c index ddd65d9fa5d7..6b623daee8e6 100644 --- a/gcc/config/avr/avr.c +++ b/gcc/config/avr/avr.c @@ -1099,6 +1099,16 @@ print_operand (FILE *file, rtx x, int code) print_operand (file, XEXP (addr, 1), 0); } + else if (code == 'p' || code == 'r') + { + if (GET_CODE (addr) != POST_INC && GET_CODE (addr) != PRE_DEC) + fatal_insn ("bad address, not post_inc or pre_dec:", addr); + + if (code == 'p') + print_operand_address (file, XEXP (addr, 0)); /* X, Y, Z */ + else + print_operand (file, XEXP (addr, 0), 0); /* r26, r28, r30 */ + } else if (GET_CODE (addr) == PLUS) { print_operand_address (file, XEXP (addr,0)); @@ -1814,6 +1824,9 @@ out_movhi_r_mr (rtx insn, rtx op[], int *l) rtx base = XEXP (src, 0); int reg_dest = true_regnum (dest); int reg_base = true_regnum (base); + /* "volatile" forces reading low byte first, even if less efficient, + for correct operation with 16-bit I/O registers. */ + int mem_volatile_p = MEM_VOLATILE_P (src); int tmp; if (!l) @@ -1907,6 +1920,25 @@ out_movhi_r_mr (rtx insn, rtx op[], int *l) if (reg_overlap_mentioned_p (dest, XEXP (base, 0))) fatal_insn ("incorrect insn:", insn); + if (mem_volatile_p) + { + if (REGNO (XEXP (base, 0)) == REG_X) + { + *l = 4; + return (AS2 (sbiw,r26,2) CR_TAB + AS2 (ld,%A0,X+) CR_TAB + AS2 (ld,%B0,X) CR_TAB + AS2 (sbiw,r26,1)); + } + else + { + *l = 3; + return (AS2 (sbiw,%r1,2) CR_TAB + AS2 (ld,%A0,%p1) CR_TAB + AS2 (ldd,%B0,%p1+1)); + } + } + *l = 2; return (AS2 (ld,%B0,%1) CR_TAB AS2 (ld,%A0,%1)); @@ -2487,7 +2519,11 @@ out_movhi_mr_r (rtx insn, rtx op[], int *l) rtx base = XEXP (dest, 0); int reg_base = true_regnum (base); int reg_src = true_regnum (src); + /* "volatile" forces writing high byte first, even if less efficient, + for correct operation with 16-bit I/O registers. */ + int mem_volatile_p = MEM_VOLATILE_P (dest); int tmp; + if (!l) l = &tmp; if (CONSTANT_ADDRESS_P (base)) @@ -2507,33 +2543,33 @@ out_movhi_mr_r (rtx insn, rtx op[], int *l) { if (reg_src == REG_X) { - /* "st X+,r26" is undefined */ - if (reg_unused_after (insn, src)) + /* "st X+,r26" and "st -X,r26" are undefined. */ + if (!mem_volatile_p && reg_unused_after (insn, src)) return *l=4, (AS2 (mov,__tmp_reg__,r27) CR_TAB AS2 (st,X,r26) CR_TAB AS2 (adiw,r26,1) CR_TAB AS2 (st,X,__tmp_reg__)); else return *l=5, (AS2 (mov,__tmp_reg__,r27) CR_TAB - AS2 (st,X,r26) CR_TAB AS2 (adiw,r26,1) CR_TAB AS2 (st,X,__tmp_reg__) CR_TAB - AS2 (sbiw,r26,1)); + AS2 (sbiw,r26,1) CR_TAB + AS2 (st,X,r26)); } else { - if (reg_unused_after (insn, base)) + if (!mem_volatile_p && reg_unused_after (insn, base)) return *l=2, (AS2 (st,X+,%A1) CR_TAB AS2 (st,X,%B1)); else - return *l=3, (AS2 (st ,X+,%A1) CR_TAB - AS2 (st ,X,%B1) CR_TAB - AS2 (sbiw,r26,1)); + return *l=3, (AS2 (adiw,r26,1) CR_TAB + AS2 (st,X,%B1) CR_TAB + AS2 (st,-X,%A1)); } } else - return *l=2, (AS2 (st ,%0,%A1) CR_TAB - AS2 (std,%0+1,%B1)); + return *l=2, (AS2 (std,%0+1,%B1) CR_TAB + AS2 (st,%0,%A1)); } else if (GET_CODE (base) == PLUS) { @@ -2546,14 +2582,14 @@ out_movhi_mr_r (rtx insn, rtx op[], int *l) if (disp <= 63 + MAX_LD_OFFSET (GET_MODE (dest))) return *l = 4, (AS2 (adiw,r28,%o0-62) CR_TAB - AS2 (std,Y+62,%A1) CR_TAB AS2 (std,Y+63,%B1) CR_TAB + AS2 (std,Y+62,%A1) CR_TAB AS2 (sbiw,r28,%o0-62)); return *l = 6, (AS2 (subi,r28,lo8(-%o0)) CR_TAB AS2 (sbci,r29,hi8(-%o0)) CR_TAB - AS2 (st,Y,%A1) CR_TAB AS2 (std,Y+1,%B1) CR_TAB + AS2 (st,Y,%A1) CR_TAB AS2 (subi,r28,lo8(%o0)) CR_TAB AS2 (sbci,r29,hi8(%o0))); } @@ -2561,31 +2597,53 @@ out_movhi_mr_r (rtx insn, rtx op[], int *l) { /* (X + d) = R */ if (reg_src == REG_X) - { + { *l = 7; return (AS2 (mov,__tmp_reg__,r26) CR_TAB AS2 (mov,__zero_reg__,r27) CR_TAB - AS2 (adiw,r26,%o0) CR_TAB - AS2 (st,X+,__tmp_reg__) CR_TAB + AS2 (adiw,r26,%o0+1) CR_TAB AS2 (st,X,__zero_reg__) CR_TAB + AS2 (st,-X,__tmp_reg__) CR_TAB AS1 (clr,__zero_reg__) CR_TAB - AS2 (sbiw,r26,%o0+1)); + AS2 (sbiw,r26,%o0)); } *l = 4; - return (AS2 (adiw,r26,%o0) CR_TAB - AS2 (st,X+,%A1) CR_TAB - AS2 (st,X,%B1) CR_TAB - AS2 (sbiw,r26,%o0+1)); + return (AS2 (adiw,r26,%o0+1) CR_TAB + AS2 (st,X,%B1) CR_TAB + AS2 (st,-X,%A1) CR_TAB + AS2 (sbiw,r26,%o0)); } - return *l=2, (AS2 (std,%A0,%A1) CR_TAB - AS2 (std,%B0,%B1)); + return *l=2, (AS2 (std,%B0,%B1) CR_TAB + AS2 (std,%A0,%A1)); } else if (GET_CODE (base) == PRE_DEC) /* (--R) */ return *l=2, (AS2 (st,%0,%B1) CR_TAB AS2 (st,%0,%A1)); else if (GET_CODE (base) == POST_INC) /* (R++) */ - return *l=2, (AS2 (st,%0,%A1) CR_TAB - AS2 (st,%0,%B1)); + { + if (mem_volatile_p) + { + if (REGNO (XEXP (base, 0)) == REG_X) + { + *l = 4; + return (AS2 (adiw,r26,1) CR_TAB + AS2 (st,X,%B1) CR_TAB + AS2 (st,-X,%A1) CR_TAB + AS2 (adiw,r26,2)); + } + else + { + *l = 3; + return (AS2 (std,%p0+1,%B1) CR_TAB + AS2 (st,%p0,%A1) CR_TAB + AS2 (adiw,%r0,2)); + } + } + + *l = 2; + return (AS2 (st,%0,%A1) CR_TAB + AS2 (st,%0,%B1)); + } fatal_insn ("unknown move insn:",insn); return ""; } diff --git a/gcc/config/avr/avr.md b/gcc/config/avr/avr.md index 7823545b9da6..aadbaf6ed4ea 100644 --- a/gcc/config/avr/avr.md +++ b/gcc/config/avr/avr.md @@ -30,6 +30,8 @@ ;; j Branch condition. ;; k Reverse branch condition. ;; o Displacement for (mem (plus (reg) (const_int))) operands. +;; p POST_INC or PRE_DEC address as a pointer (X, Y, Z) +;; r POST_INC or PRE_DEC address as a register (r26, r28, r30) ;; ~ Output 'r' if not AVR_MEGA. ;; UNSPEC usage: