Hello! Actually a v3 of TARGET_REJECT_COMBINED_INSN target hook.
Changes: - rename the hook and reverse the return value 2012-08-25 Uros Bizjak <ubiz...@gmail.com> * target.def (legitimate_combined_insn): New target hook. * doc/tm.texi.in (TARGET_LEGITIMATE_COMBINED_INSN): New hook. * doc/tm.texi: Regenerated. * combine.c (recog_for_combine): Call targetm.legitimate_combined_insn to allow targets to reject combined insn. * hooks.h (hook_bool_rtx_true): New. * hooks.c (hook_bool_rtx_true): Ditto. Bootstrapped and regression tested on x86_64-pc-linux-gnu {,-m32}, also with target-dependant x86 patch that implements the hook. Uros.
Index: target.def =================================================================== --- target.def (revision 190665) +++ target.def (working copy) @@ -1984,7 +1984,16 @@ DEFHOOK const char *, (const_rtx insn), default_invalid_within_doloop) +/* Returns true for a legitimate combined insn. */ DEFHOOK +(legitimate_combined_insn, +"Take an instruction in @var{insn} and return @code{false} if the instruction\ + is not appropriate as a combination of two or more instructions. The\ + default is to accept all instructions.", + bool, (rtx insn), + hook_bool_rtx_true) + +DEFHOOK (valid_dllimport_attribute_p, "@var{decl} is a variable or function with @code{__attribute__((dllimport))}\ specified. Use this hook if the target needs to add extra validation\ Index: hooks.c =================================================================== --- hooks.c (revision 190665) +++ hooks.c (working copy) @@ -269,6 +269,12 @@ hook_bool_tree_bool_false (tree a ATTRIBUTE_UNUSED } bool +hook_bool_rtx_true (rtx a ATTRIBUTE_UNUSED) +{ + return true; +} + +bool hook_bool_rtx_false (rtx a ATTRIBUTE_UNUSED) { return false; Index: hooks.h =================================================================== --- hooks.h (revision 190665) +++ hooks.h (working copy) @@ -50,6 +50,7 @@ extern bool hook_bool_const_tree_hwi_hwi_const_tre HOST_WIDE_INT, HOST_WIDE_INT, const_tree); +extern bool hook_bool_rtx_true (rtx); extern bool hook_bool_rtx_false (rtx); extern bool hook_bool_rtx_int_false (rtx, int); extern bool hook_bool_uintp_uintp_false (unsigned int *, unsigned int *); Index: doc/tm.texi =================================================================== --- doc/tm.texi (revision 190665) +++ doc/tm.texi (working copy) @@ -10938,6 +10938,10 @@ By default, the RTL loop optimizer does not use a loops containing function calls or branch on table instructions. @end deftypefn +@deftypefn {Target Hook} bool TARGET_LEGITIMATE_COMBINED_INSN (rtx @var{insn}) +Take an instruction in @var{insn} and return @code{false} if the instruction is not appropriate as a combination of two or more instructions. The default is to accept all instructions. +@end deftypefn + @defmac MD_CAN_REDIRECT_BRANCH (@var{branch1}, @var{branch2}) Take a branch insn in @var{branch1} and another in @var{branch2}. Index: doc/tm.texi.in =================================================================== --- doc/tm.texi.in (revision 190665) +++ doc/tm.texi.in (working copy) @@ -10796,6 +10796,8 @@ By default, the RTL loop optimizer does not use a loops containing function calls or branch on table instructions. @end deftypefn +@hook TARGET_LEGITIMATE_COMBINED_INSN + @defmac MD_CAN_REDIRECT_BRANCH (@var{branch1}, @var{branch2}) Take a branch insn in @var{branch1} and another in @var{branch2}. Index: combine.c =================================================================== --- combine.c (revision 190665) +++ combine.c (working copy) @@ -10500,11 +10500,13 @@ static int recog_for_combine (rtx *pnewpat, rtx insn, rtx *pnotes) { rtx pat = *pnewpat; + rtx pat_without_clobbers; int insn_code_number; int num_clobbers_to_add = 0; int i; - rtx notes = 0; + rtx notes = NULL_RTX; rtx old_notes, old_pat; + int old_icode; /* If PAT is a PARALLEL, check to see if it contains the CLOBBER we use to indicate that something didn't match. If we find such a @@ -10518,7 +10520,7 @@ recog_for_combine (rtx *pnewpat, rtx insn, rtx *pn old_pat = PATTERN (insn); old_notes = REG_NOTES (insn); PATTERN (insn) = pat; - REG_NOTES (insn) = 0; + REG_NOTES (insn) = NULL_RTX; insn_code_number = recog (pat, insn, &num_clobbers_to_add); if (dump_file && (dump_flags & TDF_DETAILS)) @@ -10564,6 +10566,9 @@ recog_for_combine (rtx *pnewpat, rtx insn, rtx *pn print_rtl_single (dump_file, pat); } } + + pat_without_clobbers = pat; + PATTERN (insn) = old_pat; REG_NOTES (insn) = old_notes; @@ -10605,6 +10610,35 @@ recog_for_combine (rtx *pnewpat, rtx insn, rtx *pn pat = newpat; } + if (insn_code_number >= 0 + && insn_code_number != NOOP_MOVE_INSN_CODE) + { + old_pat = PATTERN (insn); + old_notes = REG_NOTES (insn); + old_icode = INSN_CODE (insn); + PATTERN (insn) = pat; + REG_NOTES (insn) = notes; + + /* Allow targets to reject combined insn. */ + if (!targetm.legitimate_combined_insn (insn)) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + fputs ("Instruction not appropriate for target.", + dump_file); + + /* Callers expect recog_for_combine to strip + clobbers from the pattern on failure. */ + pat = pat_without_clobbers; + notes = NULL_RTX; + + insn_code_number = -1; + } + + PATTERN (insn) = old_pat; + REG_NOTES (insn) = old_notes; + INSN_CODE (insn) = old_icode; + } + *pnewpat = pat; *pnotes = notes;