On 05/03/2012 09:31 AM, Steven Bosscher wrote:
+/* This gen* file is unique, in that it writes out multiple files.
+
+ Before GCC 4.8, insn-attrtab.c was written out containing many large
+ functions and tables. This made insn-attrtab.c_the_ bottle-neck in
+ a parallel build, and even made it impossible to build GCC on machines
+ with relatively small RAM space (PR other/29442). Therefore, the
+ atrribute functions/tables are now written out to three separate
+ files: "*insn_default_latency" and "*internal_dfa_insn_code"
+ can be output to separate files, stdout and DFA_FILE_NAME respectively.
+ The remaining attributes can be output to ATTR_FILE_NAME.
+
+ Because the gen* support functions write their output to stdout, we have
+ to play tricks with freopen to redirect the output to the right files. */
+
+static const char *attr_file_name = "tmp-attrtab.c";
+static const char *dfa_file_name = "tmp-dfatab.c";
+static const char *latency_file_name = "tmp-latencytab.c";
+
+static void
+switch_stdout (const char *file_name)
+{
+ if (fflush (stdout) || ferror (stdout))
+ exit (FATAL_EXIT_CODE);
+ if (!freopen (file_name, "a", stdout))
+ fatal ("cannot open file %s: %s", file_name, xstrerror (errno));
+}
I like the idea of the split, but this is unnecessarily gross.
I see nothing in gen* support that has anything to do with output at all;
it's all about input.
I see no reason you can't pass the output filenames at the beginning of
the argument list, increment argv for passing to init_rtx_reader_args,
and use normal fopen/fclose instead of freopen.
r~
