Introduce rtx_alloca, alloca_raw_REG and alloca_rtx_fmt_*

When one passes short-lived fake rtxes to backends in order to test
their capabilities, it might be beneficial to allocate these rtxes on
stack in order to reduce the load on GC.

Provide macro counterparts of some of the gen_* functions for that
purpose.

gcc/ChangeLog:

2019-09-30  Ilya Leoshkevich  <iii@linux.ibm.com>

	* emit-rtl.c (init_raw_REG): New function.
	(gen_raw_REG): Use init_raw_REG.
	* gengenrtl.c (gendef): Emit init_* functions and alloca_*
	macros.
	* rtl.c (rtx_alloc_stat_v): Use rtx_init.
	* rtl.h (rtx_init): New function.
	(rtx_alloca): New function.
	(init_raw_REG): New function.
	(alloca_raw_REG): New macro.

From-SVN: r276303

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 74f08cc..e0acd9d 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,15 @@
+2019-09-30  Ilya Leoshkevich  <iii@linux.ibm.com>
+
+       * emit-rtl.c (init_raw_REG): New function.
+       (gen_raw_REG): Use init_raw_REG.
+       * gengenrtl.c (gendef): Emit init_* functions and alloca_*
+       macros.
+       * rtl.c (rtx_alloc_stat_v): Use rtx_init.
+       * rtl.h (rtx_init): New function.
+       (rtx_alloca): New function.
+       (init_raw_REG): New function.
+       (alloca_raw_REG): New macro.
+
 2019-09-30  Michael Meissner  <meissner@linux.ibm.com>
 
        * config/rs6000/predicates.md (pcrel_address): Delete predicate.

diff --git a/gcc/emit-rtl.c b/gcc/emit-rtl.c
index a667cda..783fdb9 100644 (file)
--- a/gcc/emit-rtl.c
+++ b/gcc/emit-rtl.c
@@ -466,6 +466,17 @@ set_mode_and_regno (rtx x, machine_mode mode, unsigned int regno)
   set_regno_raw (x, regno, nregs);
 }
 
+/* Initialize a fresh REG rtx with mode MODE and register REGNO.  */
+
+rtx
+init_raw_REG (rtx x, machine_mode mode, unsigned int regno)
+{
+  set_mode_and_regno (x, mode, regno);
+  REG_ATTRS (x) = NULL;
+  ORIGINAL_REGNO (x) = regno;
+  return x;
+}
+
 /* Generate a new REG rtx.  Make sure ORIGINAL_REGNO is set properly, and
    don't attempt to share with the various global pieces of rtl (such as
    frame_pointer_rtx).  */
@@ -474,9 +485,7 @@ rtx
 gen_raw_REG (machine_mode mode, unsigned int regno)
 {
   rtx x = rtx_alloc (REG MEM_STAT_INFO);
-  set_mode_and_regno (x, mode, regno);
-  REG_ATTRS (x) = NULL;
-  ORIGINAL_REGNO (x) = regno;
+  init_raw_REG (x, mode, regno);
   return x;
 }
 

diff --git a/gcc/gengenrtl.c b/gcc/gengenrtl.c
index 5c78fab..eebbc09 100644 (file)
--- a/gcc/gengenrtl.c
+++ b/gcc/gengenrtl.c
@@ -231,8 +231,7 @@ genmacro (int idx)
   puts (")");
 }
 
-/* Generate the code for the function to generate RTL whose
-   format is FORMAT.  */
+/* Generate the code for functions to generate RTL whose format is FORMAT.  */
 
 static void
 gendef (const char *format)
@@ -240,22 +239,18 @@ gendef (const char *format)
   const char *p;
   int i, j;
 
-  /* Start by writing the definition of the function name and the types
+  /* Write the definition of the init function name and the types
      of the arguments.  */
 
-  printf ("static inline rtx\ngen_rtx_fmt_%s_stat (RTX_CODE code, machine_mode mode", format);
+  puts ("static inline rtx");
+  printf ("init_rtx_fmt_%s (rtx rt, machine_mode mode", format);
   for (p = format, i = 0; *p != 0; p++)
     if (*p != '0')
       printf (",\n\t%sarg%d", type_from_format (*p), i++);
+  puts (")");
 
-  puts (" MEM_STAT_DECL)");
-
-  /* Now write out the body of the function itself, which allocates
-     the memory and initializes it.  */
+  /* Now write out the body of the init function itself.  */
   puts ("{");
-  puts ("  rtx rt;");
-  puts ("  rt = rtx_alloc (code PASS_MEM_STAT);\n");
-
   puts ("  PUT_MODE_RAW (rt, mode);");
 
   for (p = format, i = j = 0; *p ; ++p, ++i)
@@ -266,16 +261,53 @@ gendef (const char *format)
     else
       printf ("  %s (rt, %d) = arg%d;\n", accessor_from_format (*p), i, j++);
 
-  puts ("\n  return rt;\n}\n");
+  puts ("  return rt;\n}\n");
+
+  /* Write the definition of the gen function name and the types
+     of the arguments.  */
+
+  puts ("static inline rtx");
+  printf ("gen_rtx_fmt_%s_stat (RTX_CODE code, machine_mode mode", format);
+  for (p = format, i = 0; *p != 0; p++)
+    if (*p != '0')
+      printf (",\n\t%sarg%d", type_from_format (*p), i++);
+  puts (" MEM_STAT_DECL)");
+
+  /* Now write out the body of the function itself, which allocates
+     the memory and initializes it.  */
+  puts ("{");
+  puts ("  rtx rt;\n");
+
+  puts ("  rt = rtx_alloc (code PASS_MEM_STAT);");
+  printf ("  return init_rtx_fmt_%s (rt, mode", format);
+  for (p = format, i = 0; *p != 0; p++)
+    if (*p != '0')
+      printf (", arg%d", i++);
+  puts (");\n}\n");
+
+  /* Write the definition of gen macro.  */
+
   printf ("#define gen_rtx_fmt_%s(c, m", format);
   for (p = format, i = 0; *p != 0; p++)
     if (*p != '0')
-      printf (", p%i",i++);
-  printf (")\\\n        gen_rtx_fmt_%s_stat (c, m", format);
+      printf (", arg%d", i++);
+  printf (") \\\n  gen_rtx_fmt_%s_stat ((c), (m)", format);
   for (p = format, i = 0; *p != 0; p++)
     if (*p != '0')
-      printf (", p%i",i++);
+      printf (", (arg%d)", i++);
   printf (" MEM_STAT_INFO)\n\n");
+
+  /* Write the definition of alloca macro.  */
+
+  printf ("#define alloca_rtx_fmt_%s(c, m", format);
+  for (p = format, i = 0; *p != 0; p++)
+    if (*p != '0')
+      printf (", arg%d", i++);
+  printf (") \\\n  init_rtx_fmt_%s (rtx_alloca ((c)), (m)", format);
+  for (p = format, i = 0; *p != 0; p++)
+    if (*p != '0')
+      printf (", (arg%d)", i++);
+  printf (")\n\n");
 }
 
 /* Generate the documentation header for files we write.  */

diff --git a/gcc/rtl.c b/gcc/rtl.c
index d7b8e98..0be52d3 100644 (file)
--- a/gcc/rtl.c
+++ b/gcc/rtl.c
@@ -219,12 +219,7 @@ rtx_alloc_stat_v (RTX_CODE code MEM_STAT_DECL, int extra)
   rtx rt = ggc_alloc_rtx_def_stat (RTX_CODE_SIZE (code) + extra
                                   PASS_MEM_STAT);
 
-  /* We want to clear everything up to the FLD array.  Normally, this
-     is one int, but we don't want to assume that and it isn't very
-     portable anyway; this is.  */
-
-  memset (rt, 0, RTX_HDR_SIZE);
-  PUT_CODE (rt, code);
+  rtx_init (rt, code);
 
   if (GATHER_STATISTICS)
     {

diff --git a/gcc/rtl.h b/gcc/rtl.h
index 9cadac7..b75b3ed 100644 (file)
--- a/gcc/rtl.h
+++ b/gcc/rtl.h
@@ -2957,6 +2957,15 @@ extern HOST_WIDE_INT get_stack_check_protect (void);
 
 /* In rtl.c */
 extern rtx rtx_alloc (RTX_CODE CXX_MEM_STAT_INFO);
+inline rtx
+rtx_init (rtx rt, RTX_CODE code)
+{
+  memset (rt, 0, RTX_HDR_SIZE);
+  PUT_CODE (rt, code);
+  return rt;
+}
+#define rtx_alloca(code) \
+  rtx_init ((rtx) alloca (RTX_CODE_SIZE ((code))), (code))
 extern rtx rtx_alloc_stat_v (RTX_CODE MEM_STAT_DECL, int);
 #define rtx_alloc_v(c, SZ) rtx_alloc_stat_v (c MEM_STAT_INFO, SZ)
 #define const_wide_int_alloc(NWORDS)                           \
@@ -3823,7 +3832,10 @@ gen_rtx_INSN (machine_mode mode, rtx_insn *prev_insn, rtx_insn *next_insn,
 extern rtx gen_rtx_CONST_INT (machine_mode, HOST_WIDE_INT);
 extern rtx gen_rtx_CONST_VECTOR (machine_mode, rtvec);
 extern void set_mode_and_regno (rtx, machine_mode, unsigned int);
+extern rtx init_raw_REG (rtx, machine_mode, unsigned int);
 extern rtx gen_raw_REG (machine_mode, unsigned int);
+#define alloca_raw_REG(mode, regno) \
+  init_raw_REG (rtx_alloca (REG), (mode), (regno))
 extern rtx gen_rtx_REG (machine_mode, unsigned int);
 extern rtx gen_rtx_SUBREG (machine_mode, rtx, poly_uint64);
 extern rtx gen_rtx_MEM (machine_mode, rtx);