From patchwork Thu Sep 27 22:58:32 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: RFC: LRA for x86/x86-64 [6/9] Date: Thu, 27 Sep 2012 12:58:32 -0000 From: Vladimir Makarov X-Patchwork-Id: 187523 Message-Id: <5064DA18.20404@redhat.com> To: GCC Patches The following patch modifies some code in the rest of compiler for correct work of LRA. The code works the same way when LRA is not used. It is achieved by checking a new variable lra_in_progress. 2012-09-27 Vladimir Makarov * rtlanal.c (simplify_subreg_regno): Permit ARG_POINTER_REGNUM and STACK_POINTER_REGNU for LRA. * jump.c (true_regnum): Always use hard_regno for subreg_get_info when lra is in progress. * expr.c (emit_move_insn_1): Pass an additional argument to emit_move_via_integer. Use emit_move_via_integer for LRA only if the insn is recognized. * recog.c (general_operand, register_operand): Accept paradoxical FLOAD_MODE subregs for LRA. (scratch_operand): Accept pseudos for LRA. * emit-rtl.c (gen_rtx_REG): Add lra_in_progress. (validate_subreg): Don't check offset for LRA and floating point modes. * rtl.h (lra_in_progress): New external. * ira.c (lra_in_progress): Define. Index: rtl.h =================================================================== --- rtl.h (revision 191771) +++ rtl.h (working copy) @@ -2369,6 +2369,9 @@ extern int epilogue_completed; extern int reload_in_progress; +/* Set to 1 while in lra. */ +extern int lra_in_progress; + /* This macro indicates whether you may create a new pseudo-register. */ Index: ira.c =================================================================== --- ira.c (revision 191771) +++ ira.c (working copy) @@ -4308,6 +4308,9 @@ bool ira_conflicts_p; /* Saved between IRA and reload. */ static int saved_flag_ira_share_spill_slots; +/* Set to 1 while in lra. */ +int lra_in_progress = 0; + /* This is the main entry of IRA. */ static void ira (FILE *f) Index: jump.c =================================================================== --- jump.c (revision 191771) +++ jump.c (working copy) @@ -1868,7 +1868,8 @@ true_regnum (const_rtx x) { if (REG_P (x)) { - if (REGNO (x) >= FIRST_PSEUDO_REGISTER && reg_renumber[REGNO (x)] >= 0) + if (REGNO (x) >= FIRST_PSEUDO_REGISTER + && (lra_in_progress || reg_renumber[REGNO (x)] >= 0)) return reg_renumber[REGNO (x)]; return REGNO (x); } @@ -1880,7 +1881,8 @@ true_regnum (const_rtx x) { struct subreg_info info; - subreg_get_info (REGNO (SUBREG_REG (x)), + subreg_get_info (lra_in_progress + ? (unsigned) base : REGNO (SUBREG_REG (x)), GET_MODE (SUBREG_REG (x)), SUBREG_BYTE (x), GET_MODE (x), &info); Index: rtlanal.c =================================================================== --- rtlanal.c (revision 191771) +++ rtlanal.c (working copy) @@ -3465,7 +3465,9 @@ simplify_subreg_regno (unsigned int xreg /* Give the backend a chance to disallow the mode change. */ if (GET_MODE_CLASS (xmode) != MODE_COMPLEX_INT && GET_MODE_CLASS (xmode) != MODE_COMPLEX_FLOAT - && REG_CANNOT_CHANGE_MODE_P (xregno, xmode, ymode)) + && REG_CANNOT_CHANGE_MODE_P (xregno, xmode, ymode) + /* We can use mode change in LRA for some transformations. */ + && ! lra_in_progress) return -1; #endif @@ -3475,10 +3477,16 @@ simplify_subreg_regno (unsigned int xreg return -1; if (FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM - && xregno == ARG_POINTER_REGNUM) + /* We should convert arg register in LRA after the elimination + if it is possible. */ + && xregno == ARG_POINTER_REGNUM + && ! lra_in_progress) return -1; - if (xregno == STACK_POINTER_REGNUM) + if (xregno == STACK_POINTER_REGNUM + /* We should convert hard stack register in LRA if it is + possible. */ + && ! lra_in_progress) return -1; /* Try to get the register offset. */ Index: emit-rtl.c =================================================================== --- emit-rtl.c (revision 191771) +++ emit-rtl.c (working copy) @@ -581,7 +581,7 @@ gen_rtx_REG (enum machine_mode mode, uns Also don't do this when we are making new REGs in reload, since we don't want to get confused with the real pointers. */ - if (mode == Pmode && !reload_in_progress) + if (mode == Pmode && !reload_in_progress && !lra_in_progress) { if (regno == FRAME_POINTER_REGNUM && (!reload_completed || frame_pointer_needed)) @@ -723,7 +723,14 @@ validate_subreg (enum machine_mode omode (subreg:SI (reg:DF) 0) isn't. */ else if (FLOAT_MODE_P (imode) || FLOAT_MODE_P (omode)) { - if (isize != osize) + if (! (isize == osize + /* LRA can use subreg to store a floating point value in + an integer mode. Although the floating point and the + integer modes need the same number of hard registers, + the size of floating point mode can be less than the + integer mode. LRA also uses subregs for a register + should be used in different mode in on insn. */ + || lra_in_progress)) return false; } @@ -756,7 +763,8 @@ validate_subreg (enum machine_mode omode of a subword. A subreg does *not* perform arbitrary bit extraction. Given that we've already checked mode/offset alignment, we only have to check subword subregs here. */ - if (osize < UNITS_PER_WORD) + if (osize < UNITS_PER_WORD + && ! (lra_in_progress && (FLOAT_MODE_P (imode) || FLOAT_MODE_P (omode)))) { enum machine_mode wmode = isize > UNITS_PER_WORD ? word_mode : imode; unsigned int low_off = subreg_lowpart_offset (omode, wmode); Index: expr.c =================================================================== --- expr.c (revision 191771) +++ expr.c (working copy) @@ -3434,9 +3434,13 @@ emit_move_insn_1 (rtx x, rtx y) fits within a HOST_WIDE_INT. */ if (!CONSTANT_P (y) || GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT) { - rtx ret = emit_move_via_integer (mode, x, y, false); + rtx ret = emit_move_via_integer (mode, x, y, lra_in_progress); + if (ret) - return ret; + { + if (! lra_in_progress || recog (PATTERN (ret), ret, 0) >= 0) + return ret; + } } return emit_move_multi_word (mode, x, y); Index: recog.c =================================================================== --- recog.c (revision 191771) +++ recog.c (working copy) @@ -993,6 +993,12 @@ general_operand (rtx op, enum machine_mo /* FLOAT_MODE subregs can't be paradoxical. Combine will occasionally create such rtl, and we must reject it. */ if (SCALAR_FLOAT_MODE_P (GET_MODE (op)) + /* LRA can use subreg to store a floating point value in an + integer mode. Although the floating point and the + integer modes need the same number of hard registers, the + size of floating point mode can be less than the integer + mode. */ + && ! lra_in_progress && GET_MODE_SIZE (GET_MODE (op)) > GET_MODE_SIZE (GET_MODE (sub))) return 0; @@ -1068,6 +1074,12 @@ register_operand (rtx op, enum machine_m /* FLOAT_MODE subregs can't be paradoxical. Combine will occasionally create such rtl, and we must reject it. */ if (SCALAR_FLOAT_MODE_P (GET_MODE (op)) + /* LRA can use subreg to store a floating point value in an + integer mode. Although the floating point and the + integer modes need the same number of hard registers, the + size of floating point mode can be less than the integer + mode. */ + && ! lra_in_progress && GET_MODE_SIZE (GET_MODE (op)) > GET_MODE_SIZE (GET_MODE (sub))) return 0; @@ -1099,7 +1111,7 @@ scratch_operand (rtx op, enum machine_mo return (GET_CODE (op) == SCRATCH || (REG_P (op) - && REGNO (op) < FIRST_PSEUDO_REGISTER)); + && (lra_in_progress || REGNO (op) < FIRST_PSEUDO_REGISTER))); } /* Return 1 if OP is a valid immediate operand for mode MODE.