From: Maciej W. Rozycki Date: Fri, 8 Jan 2021 01:50:10 +0000 (+0000) Subject: RTL: Update `const_double_zero' handling for mode and callable insns X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=859be2e44aceb3766e4517e827e2aad7c9711b4c;p=gcc.git RTL: Update `const_double_zero' handling for mode and callable insns Handle machine mode specification with `const_double_zero' and handle the rtx with callable code produced from named insns. Complementing commit 20ab43b5cad6 ("RTL: Add `const_double_zero' syntactic rtx") and removing a commit c60d0736dff7 ("PDP11: Use `const_double_zero' to express double zero constant") build regression observed with the `pdp11-aout' target: genemit: Internal error: abort in gen_exp, at genemit.c:202 make[2]: *** [Makefile:2427: s-emit] Error 1 where a: (const_double 0 [0] 0 [0] 0 [0] 0 [0]) rtx coming from: (parallel [ (set (reg:CC 16) (compare:CC (abs:DF (match_operand:DF 1 ("general_operand") ("0,0"))) (const_double 0 [0] 0 [0] 0 [0] 0 [0]))) (set (match_operand:DF 0 ("nonimmediate_operand") ("=fR,Q")) (abs:DF (match_dup 1))) ]) and ultimately `(const_double_zero)' referred in a named RTL insn cannot be interpreted. Handle the rtx then by supplying the constant 0 double operand requested, resulting in the following update to insn-emit.c code produced for the `pdp11-aout' target, relative to before the triggering commit: @@ -1514,7 +1514,7 @@ gen_absdf2_cc (rtx operand0 ATTRIBUTE_UN gen_rtx_COMPARE (CCmode, gen_rtx_ABS (DFmode, operand1), - const0_rtx)), + CONST_DOUBLE_ATOF ("0", VOIDmode))), gen_rtx_SET (operand0, gen_rtx_ABS (DFmode, copy_rtx (operand1))))); @@ -1555,7 +1555,7 @@ gen_negdf2_cc (rtx operand0 ATTRIBUTE_UN gen_rtx_COMPARE (CCmode, gen_rtx_NEG (DFmode, operand1), - const0_rtx)), + CONST_DOUBLE_ATOF ("0", VOIDmode))), gen_rtx_SET (operand0, gen_rtx_NEG (DFmode, copy_rtx (operand1))))); @@ -1790,7 +1790,7 @@ gen_muldf3_cc (rtx operand0 ATTRIBUTE_UN gen_rtx_MULT (DFmode, operand1, operand2), - const0_rtx)), + CONST_DOUBLE_ATOF ("0", VOIDmode))), gen_rtx_SET (operand0, gen_rtx_MULT (DFmode, copy_rtx (operand1), @@ -1942,7 +1942,7 @@ gen_divdf3_cc (rtx operand0 ATTRIBUTE_UN gen_rtx_DIV (DFmode, operand1, operand2), - const0_rtx)), + CONST_DOUBLE_ATOF ("0", VOIDmode))), gen_rtx_SET (operand0, gen_rtx_DIV (DFmode, copy_rtx (operand1), This does not (yet) remove VOIDmode CONST_DOUBLE use, as it is up to individual machine descriptions to choose. gcc/ * genemit.c (gen_exp) : Handle `const_double_zero' rtx. * read-rtl.c (rtx_reader::read_rtx_code): Handle machine mode with `const_double_zero'. * doc/rtl.texi (Constant Expression Types): Document it. --- diff --git a/gcc/doc/rtl.texi b/gcc/doc/rtl.texi index 69c481fb7a4..edbc60fdfba 100644 --- a/gcc/doc/rtl.texi +++ b/gcc/doc/rtl.texi @@ -1719,13 +1719,13 @@ of code @code{const_double} and therefore a syntactic alias has been provided: @smallexample -(const_double_zero) +(const_double_zero:@var{m}) @end smallexample standing for: @smallexample -(const_double 0 0 @dots{}) +(const_double:@var{m} 0 0 @dots{}) @end smallexample for matching the floating-point value zero, possibly the only useful one. diff --git a/gcc/genemit.c b/gcc/genemit.c index 3cd6499037d..89d9e990b73 100644 --- a/gcc/genemit.c +++ b/gcc/genemit.c @@ -195,6 +195,14 @@ gen_exp (rtx x, enum rtx_code subroutine_type, char *used, md_rtx_info *info) return; case CONST_DOUBLE: + /* Handle `const_double_zero' rtx. */ + if (CONST_DOUBLE_REAL_VALUE (x)->cl == rvc_zero) + { + printf ("CONST_DOUBLE_ATOF (\"0\", %smode)", + GET_MODE_NAME (GET_MODE (x))); + return; + } + /* Fall through. */ case CONST_FIXED: case CONST_WIDE_INT: /* These shouldn't be written in MD files. Instead, the appropriate diff --git a/gcc/read-rtl.c b/gcc/read-rtl.c index 11e2686262c..925402877ec 100644 --- a/gcc/read-rtl.c +++ b/gcc/read-rtl.c @@ -1658,6 +1658,15 @@ rtx_reader::read_rtx_code (const char *code_name) return_rtx = rtx_alloc (code); memset (return_rtx, 0, RTX_CODE_SIZE (code)); PUT_CODE (return_rtx, code); + c = read_skip_spaces (); + if (c == ':') + { + file_location loc = read_name (&name); + record_potential_iterator_use (&modes, loc, return_rtx, 0, + name.string); + } + else + unread_char (c); return return_rtx; }