Re: [PATCH 06/12] revert "x86: Also pass -P to $(CPP) when processing i386-opc.tbl"

["H.J. Lu" <hjl.tools@gmail.com>]

On Fri, Aug 5, 2022 at 5:23 AM Jan Beulich <jbeulich@suse.com> wrote:
>
> This reverts commit 384f368958f2a5bb083660e58e5f8a010e6ad429, which
> broke i386-gen's emitting of diagnostics. As a replacement to address
> the original issue of newer gcc no longer splicing lines when dropping
> the line continuation backslashes, switch to using + as the line
> continuation character, doing the line splicing in i386-gen.
> ---
> Alternatives to using + that I see are &, \+, or \&. To me a single

Will \\ work?

> character looks preferable, but I don't really have a strong opinion on
> + vs &. An option would be to additionally require "," to be the last
> "real" character before a line continuation, reducing the risk of
> ambiguity. Yet another alternative would be to recognize template
> definitions as the only constructs (currently) wanting to be split
> across lines, and do line splicing just for them by looking for the
> trailing > character.
>
> --- a/opcodes/Makefile.am
> +++ b/opcodes/Makefile.am
> @@ -559,7 +559,7 @@ $(srcdir)/i386-tbl.h: $(srcdir)/i386-ini
>         @echo $@
>
>  $(srcdir)/i386-init.h: @MAINT@ i386-gen$(EXEEXT_FOR_BUILD) i386-opc.tbl i386-reg.tbl i386-opc.h
> -       $(CPP) -P $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) - \
> +       $(CPP) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) - \
>                 < $(srcdir)/i386-opc.tbl \
>                 | ./i386-gen$(EXEEXT_FOR_BUILD) --srcdir $(srcdir)
>
> --- a/opcodes/Makefile.in
> +++ b/opcodes/Makefile.in
> @@ -1534,7 +1534,7 @@ $(srcdir)/i386-tbl.h: $(srcdir)/i386-ini
>         @echo $@
>
>  $(srcdir)/i386-init.h: i386-gen$(EXEEXT_FOR_BUILD) i386-opc.tbl i386-reg.tbl i386-opc.h
> -       $(CPP) -P $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) - \
> +       $(CPP) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) - \
>                 < $(srcdir)/i386-opc.tbl \
>                 | ./i386-gen$(EXEEXT_FOR_BUILD) --srcdir $(srcdir)
>
> --- a/opcodes/i386-gen.c
> +++ b/opcodes/i386-gen.c
> @@ -1764,17 +1764,36 @@ process_i386_opcodes (FILE *table)
>        if (fgets (buf, sizeof (buf), fp) == NULL)
>         break;
>
> -      lineno++;
> -
>        p = remove_leading_whitespaces (buf);
>
> -      /* Skip comments.  */
> -      str = strstr (p, "//");
> -      if (str != NULL)
> -       str[0] = '\0';
> +      for ( ; ; )
> +       {
> +         lineno++;
> +
> +         /* Skip comments.  */
> +         str = strstr (p, "//");
> +         if (str != NULL)
> +           {
> +             str[0] = '\0';
> +             remove_trailing_whitespaces (p);
> +             break;
> +           }
> +
> +         /* Look for line continuation character.  */
> +         remove_trailing_whitespaces (p);
> +         j = strlen (buf);
> +         if (!j || buf[j - 1] != '+')
> +           break;
> +         if (j >= sizeof (buf) - 1)
> +           fail (_("%s: %d: (continued) line too long\n"), filename, lineno);
>
> -      /* Remove trailing white spaces.  */
> -      remove_trailing_whitespaces (p);
> +         if (fgets (buf + j - 1, sizeof (buf) - j + 1, fp) == NULL)
> +           {
> +             fprintf (stderr, "%s: Line continuation on last line?\n",
> +                      filename);
> +             break;
> +           }
> +       }
>
>        switch (p[0])
>         {
> --- a/opcodes/i386-opc.tbl
> +++ b/opcodes/i386-opc.tbl
> @@ -455,7 +455,7 @@ enter, 0xc8, None, Cpu64, DefaultSize|No
>  leave, 0xc9, None, Cpu186|CpuNo64, DefaultSize|No_bSuf|No_sSuf|No_qSuf|No_ldSuf, {}
>  leave, 0xc9, None, Cpu64, DefaultSize|No_bSuf|No_lSuf|No_sSuf|No_ldSuf|NoRex64, {}
>
> -<cc:opc, o:0, no:1, b:2, c:2, nae:2, nb:3, nc:3, ae:3, e:4, z:4, ne:5, nz:5, be:6, na:6, nbe:7, a:7, \
> +<cc:opc, o:0, no:1, b:2, c:2, nae:2, nb:3, nc:3, ae:3, e:4, z:4, ne:5, nz:5, be:6, na:6, nbe:7, a:7, +
>           s:8, ns:9, p:a, pe:a, np:b, po:b, l:c, nge:c, nl:d, ge:d, le:e, ng:e, nle:f, g:f>
>
>  // Conditional jumps.
> @@ -871,9 +871,9 @@ rex.wrxb, 0x4f, None, Cpu64, No_bSuf|No_
>
>  // Pseudo prefixes (base_opcode == PSEUDO_PREFIX)
>
> -<pseudopfx:ident:cpu, disp8:Disp8:0, disp16:Disp16:0, disp32:Disp32:0, \
> -                      load:Load:0, store:Store:0, \
> -                      vex:VEX:0, vex2:VEX:0, vex3:VEX3:0, evex:EVEX:0, \
> +<pseudopfx:ident:cpu, disp8:Disp8:0, disp16:Disp16:0, disp32:Disp32:0, +
> +                      load:Load:0, store:Store:0, +
> +                      vex:VEX:0, vex2:VEX:0, vex3:VEX3:0, evex:EVEX:0, +
>                        rex:REX:Cpu64, nooptimize:NoOptimize:0>
>
>  {<pseudopfx>}, PSEUDO_PREFIX, Prefix_<pseudopfx:ident>, <pseudopfx:cpu>, No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf|IsPrefix, {}
> @@ -962,13 +962,13 @@ pause, 0xf390, None, Cpu186, No_bSuf|No_
>
>  // MMX/SSE2 instructions.
>
> -<mmx:cpu:pfx:attr:shimm:reg:mem, \
> -    $avx:CpuAVX:66:Vex128|VexVVVV|VexW0|SSE2AVX:Vex128|VexVVVV=2|VexW0|SSE2AVX:RegXMM:Xmmword, \
> -    $sse:CpuSSE2:66:::RegXMM:Xmmword, \
> +<mmx:cpu:pfx:attr:shimm:reg:mem, +
> +    $avx:CpuAVX:66:Vex128|VexVVVV|VexW0|SSE2AVX:Vex128|VexVVVV=2|VexW0|SSE2AVX:RegXMM:Xmmword, +
> +    $sse:CpuSSE2:66:::RegXMM:Xmmword, +
>      $mmx:CpuMMX::NoRex64::RegMMX:Qword>
>
> -<sse2:cpu:attr:scal:vvvv:shimm, \
> -    $avx:CpuAVX:Vex128|VexW0|SSE2AVX:VexLIG|VexW0|SSE2AVX:VexVVVV:Vex128|VexVVVV=2|VexW0|SSE2AVX, \
> +<sse2:cpu:attr:scal:vvvv:shimm, +
> +    $avx:CpuAVX:Vex128|VexW0|SSE2AVX:VexLIG|VexW0|SSE2AVX:VexVVVV:Vex128|VexVVVV=2|VexW0|SSE2AVX, +
>      $sse:CpuSSE2::NoRex64::>
>
>  emms, 0xf77, None, CpuMMX, No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, {}
> @@ -1052,8 +1052,8 @@ pxor<mmx>, 0x<mmx:pfx>0fef, None, <mmx:c
>
>  // SSE instructions.
>
> -<sse:cpu:attr:scal:vvvv, \
> -    $avx:CpuAVX:Vex128|VexW0|SSE2AVX:VexLIG|VexW0|SSE2AVX:VexVVVV, \
> +<sse:cpu:attr:scal:vvvv, +
> +    $avx:CpuAVX:Vex128|VexW0|SSE2AVX:VexLIG|VexW0|SSE2AVX:VexVVVV, +
>      $sse:CpuSSE::IgnoreSize:>
>  <sse_frel:imm:comm, eq:0:C, lt:1:, le:2:, unord:3:C, neq:4:C, nlt:5:, nle:6:, ord:7:C>
>
> @@ -1309,9 +1309,9 @@ invpcid, 0x660f3882, None, CpuINVPCID|Cp
>
>  // SSSE3 instructions.
>
> -<ssse3:cpu:pfx:attr:vvvv:reg:mem, \
> -    $avx:CpuAVX:66:Vex128|VexW0|SSE2AVX:VexVVVV:RegXMM:Xmmword, \
> -    $sse:CpuSSSE3:66:::RegXMM:Xmmword, \
> +<ssse3:cpu:pfx:attr:vvvv:reg:mem, +
> +    $avx:CpuAVX:66:Vex128|VexW0|SSE2AVX:VexVVVV:RegXMM:Xmmword, +
> +    $sse:CpuSSSE3:66:::RegXMM:Xmmword, +
>      $mmx:CpuSSSE3::NoRex64::RegMMX:Qword>
>
>  phaddw<ssse3>, 0x<ssse3:pfx>0f3801, None, <ssse3:cpu>, Modrm|<ssse3:attr>|<ssse3:vvvv>|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { <ssse3:reg>|<ssse3:mem>|Unspecified|BaseIndex, <ssse3:reg> }
> @@ -1469,14 +1469,14 @@ gf2p8mulb<gfni>, 0x660f38cf, None, <gfni
>
>  // AVX instructions.
>
> -<avx_frel:imm:comm, eq:00:C, eq_oq:00:C, lt:01:, lt_os:01:, le:02:, le_os:02:, \
> -    unord:03:C, unord_q:03:C, neq:04:C, neq_uq:04:C, nlt:05:, nlt_us:05:, \
> -    nle:06:, nle_us:06:, ord:07:C, ord_q:07:C, eq_uq:08:C, \
> -    nge:09:, nge_us:09:, ngt:0a:, ngt_us:0a:, false:0b:C, false_oq:0b:C, \
> -    neq_oq:0c:C, ge:0d:, ge_os:0d:, gt:0e:, gt_os:0e:, true:0f:C, \
> -    true_uq:0f:C, eq_os:10:C, lt_oq:11:, le_oq:12:, \
> -    unord_s:13:C, neq_us:14:C, nlt_uq:15:, nle_uq:16:, ord_s:17:C, eq_us:18:C, \
> -    nge_uq:19:, ngt_uq:1a:, false_os:1b:C, neq_os:1c:C, ge_oq:1d:, gt_oq:1e:, \
> +<avx_frel:imm:comm, eq:00:C, eq_oq:00:C, lt:01:, lt_os:01:, le:02:, le_os:02:, +
> +    unord:03:C, unord_q:03:C, neq:04:C, neq_uq:04:C, nlt:05:, nlt_us:05:, +
> +    nle:06:, nle_us:06:, ord:07:C, ord_q:07:C, eq_uq:08:C, +
> +    nge:09:, nge_us:09:, ngt:0a:, ngt_us:0a:, false:0b:C, false_oq:0b:C, +
> +    neq_oq:0c:C, ge:0d:, ge_os:0d:, gt:0e:, gt_os:0e:, true:0f:C, +
> +    true_uq:0f:C, eq_os:10:C, lt_oq:11:, le_oq:12:, +
> +    unord_s:13:C, neq_us:14:C, nlt_uq:15:, nle_uq:16:, ord_s:17:C, eq_us:18:C, +
> +    nge_uq:19:, ngt_uq:1a:, false_os:1b:C, neq_os:1c:C, ge_oq:1d:, gt_oq:1e:, +
>      true_us:1f:C>
>
>  vaddpd, 0x6658, None, CpuAVX, Modrm|Vex|Space0F|VexVVVV=1|VexWIG|CheckRegSize|No_bSuf|No_wSuf|No_lSuf|No_sSuf|No_qSuf|No_ldSuf, { Unspecified|BaseIndex|RegXMM|RegYMM, RegXMM|RegYMM, RegXMM|RegYMM }
>


-- 
H.J.