[src/trunk]: src/sys/arch/sparc/include Instead of using a matrix of configur...

[thorpej <thorpej%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/0e76b88d49aa
branches:  trunk
changeset: 534114:0e76b88d49aa
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Wed Jul 17 05:57:47 2002 +0000

description:
Instead of using a matrix of configured CPU types, first count
how many CPU types are configured into the kernel.  Then, use this
information to define the CPU predicate macros according to the
following rules:

1. If support for a CPU type is not configured into the kernel,
   then the test is always false.

2. Otherwise, if only one CPU type is configured into the kernel,
   then the test is always true.

3. Otherwise, we have to reference the cputyp variable.

Use a similar strategy for short-cutting the page size related
definitions.

diffstat:

 sys/arch/sparc/include/param.h |  108 +++++++++++++++++++---------------------
 1 files changed, 52 insertions(+), 56 deletions(-)

diffs (135 lines):

diff -r 84cfa98ee6ff -r 0e76b88d49aa sys/arch/sparc/include/param.h
--- a/sys/arch/sparc/include/param.h    Wed Jul 17 04:56:49 2002 +0000
+++ b/sys/arch/sparc/include/param.h    Wed Jul 17 05:57:47 2002 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: param.h,v 1.53 2002/07/17 04:55:57 thorpej Exp $ */
+/*     $NetBSD: param.h,v 1.54 2002/07/17 05:57:47 thorpej Exp $ */
 
 /*
  * Copyright (c) 1992, 1993
@@ -198,74 +198,70 @@
 #endif /* MSIIEP */
 
 /*
- * Shorthand CPU-type macros. Enumerate all eight cases.
- * Let compiler optimize away code conditional on constants.
+ * Shorthand CPU-type macros.  Let compiler optimize away code
+ * conditional on constants.
+ */
+
+/*
+ * Step 1: Count the number of CPU types configured into the
+ * kernel.
+ */
+#define        CPU_NTYPES      (defined(SUN4) + defined(SUN4C) + \
+                        defined(SUN4M))
+
+/*
+ * Step 2: Define the CPU type predicates.  Rules:
  *
- * On a sun4 machine, the page size is 8192, while on a sun4c and sun4m
- * it is 4096. Therefore, in the (SUN4 && (SUN4C || SUN4M)) cases below,
- * NBPG, PGOFSET and PGSHIFT are defined as variables which are initialized
- * early in locore.s after the machine type has been detected.
+ *     * If support for a CPU type is not configured into
+ *       the kernel, the test is always false.
  *
- * Note that whenever the macros defined below evaluate to expressions
- * involving variables, the kernel will perform slighly worse due to the
- * extra memory references they'll generate.
+ *     * Otherwise, if there is only one CPU type configured
+ *       in to the kernel, then the test is always true.
+ *
+ *     * Otherwise, we have to reference the cputyp variable.
  */
-#define CPU_ISSUN4U    (0)
-#if   defined(SUN4M) && defined(SUN4C) && defined(SUN4)
-#      define CPU_ISSUN4M      (cputyp == CPU_SUN4M)
-#      define CPU_ISSUN4C      (cputyp == CPU_SUN4C)
+#if !defined(SUN4)
+#      define CPU_ISSUN4       (0)
+#elif CPU_NTYPES == 1
+#      define CPU_ISSUN4       (1)
+#else
 #      define CPU_ISSUN4       (cputyp == CPU_SUN4)
-#      define NBPG             nbpg
-#      define PGOFSET          pgofset
-#      define PGSHIFT          pgshift
-#elif defined(SUN4M) && defined(SUN4C) && !defined(SUN4)
+#endif
+
+#if !defined(SUN4C)
+#      define CPU_ISSUN4C      (0)
+#elif CPU_NTYPES == 1
+#      define CPU_ISSUN4C      (1)
+#else
+#      define CPU_ISSUN4C      (cputyp == CPU_SUN4C)
+#endif
+
+#if !defined(SUN4M)
+#      define CPU_ISSUN4M      (0)
+#elif CPU_NTYPES == 1
+#      define CPU_ISSUN4M      (1)
+#else
 #      define CPU_ISSUN4M      (cputyp == CPU_SUN4M)
-#      define CPU_ISSUN4C      (cputyp == CPU_SUN4C)
-#      define CPU_ISSUN4       (0)
+#endif
+
+#define        CPU_ISSUN4U             (0)
+
+/*
+ * Step 3: Sun4 machines have a page size of 8192.  All other machines
+ * have a page size of 4096.  Short cut page size variables if we can.
+ */
+#if !defined(SUN4)
 #      define NBPG             4096
 #      define PGOFSET          (NBPG-1)
 #      define PGSHIFT          SUN4CM_PGSHIFT
-#elif defined(SUN4M) && !defined(SUN4C) && defined(SUN4)
-#      define CPU_ISSUN4M      (cputyp == CPU_SUN4M)
-#      define CPU_ISSUN4C      (0)
-#      define CPU_ISSUN4       (cputyp == CPU_SUN4)
-#      define NBPG             nbpg
-#      define PGOFSET          pgofset
-#      define PGSHIFT          pgshift
-#elif defined(SUN4M) && !defined(SUN4C) && !defined(SUN4)
-#      define CPU_ISSUN4M      (1)
-#      define CPU_ISSUN4C      (0)
-#      define CPU_ISSUN4       (0)
-#      define NBPG             4096
-#      define PGOFSET          (NBPG-1)
-#      define PGSHIFT          SUN4CM_PGSHIFT
-#elif !defined(SUN4M) && defined(SUN4C) && defined(SUN4)
-#      define CPU_ISSUN4M      (0)
-#      define CPU_ISSUN4C      (cputyp == CPU_SUN4C)
-#      define CPU_ISSUN4       (cputyp == CPU_SUN4)
-#      define NBPG             nbpg
-#      define PGOFSET          pgofset
-#      define PGSHIFT          pgshift
-#elif !defined(SUN4M) && defined(SUN4C) && !defined(SUN4)
-#      define CPU_ISSUN4M      (0)
-#      define CPU_ISSUN4C      (1)
-#      define CPU_ISSUN4       (0)
-#      define NBPG             4096
-#      define PGOFSET          (NBPG-1)
-#      define PGSHIFT          SUN4CM_PGSHIFT
-#elif !defined(SUN4M) && !defined(SUN4C) && defined(SUN4)
-#      define CPU_ISSUN4M      (0)
-#      define CPU_ISSUN4C      (0)
-#      define CPU_ISSUN4       (1)
+#elif CPU_NTYPES == 1  /* only SUN4 */
 #      define NBPG             8192
 #      define PGOFSET          (NBPG-1)
 #      define PGSHIFT          SUN4_PGSHIFT
-#elif !defined(SUN4M) && !defined(SUN4C) && !defined(SUN4)
-#      define CPU_ISSUN4M      (cputyp == CPU_SUN4M)
-#      define CPU_ISSUN4C      (cputyp == CPU_SUN4C)
-#      define CPU_ISSUN4       (cputyp == CPU_SUN4)
+#else                  /* more than one type */
 #      define NBPG             nbpg
 #      define PGOFSET          pgofset
 #      define PGSHIFT          pgshift
 #endif
+
 #endif /* _KERNEL || _STANDALONE */