From 13f52d26149c900378d315478779b02753ae2826 Mon Sep 17 00:00:00 2001
From: Garret Kelly <gdk@google.com>
Date: Thu, 26 May 2016 09:45:37 -0400
Subject: Improve handling of --with-arch in configure.ac

Augment the handling of --with-arch such that it can properly set XLEN,
atomics flags, and floating point flags.  The original
--enable-atomics/float flags are still respected, but if --with-arch is
provided then it supersedes other options.
---
 configure.ac | 45 ++++++++++++++++++++++++++++++++++-----------
 1 file changed, 34 insertions(+), 11 deletions(-)

(limited to 'configure.ac')

diff --git a/configure.ac b/configure.ac
index 3baa839..a8bc9e1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2,6 +2,7 @@ AC_INIT(riscv-toolchain, 1.0)
 
 AC_PROG_CC
 AC_PROG_FGREP
+AC_PROG_GREP
 
 AC_PATH_PROG([BASH], [bash],
 	[AC_MSG_ERROR([bash not found])])
@@ -56,13 +57,6 @@ AC_ARG_WITH(xlen,
 	AC_SUBST(XLEN, 64)
 	)
 
-AC_ARG_WITH(arch,
-	[AS_HELP_STRING([--with-arch=IMAFD],
-		[Sets the base RISC-V ISA, defaults to IMAFD])],
-	AC_SUBST(WITH_ARCH, --with-arch=$withval),
-	AC_SUBST(WITH_ARCH,)
-	)
-
 AC_ARG_ENABLE(atomic,
 	[AS_HELP_STRING([--disable-atomic],
 		[disable use of atomic memory instructions in glibc @<:@--enable-atomic@:>@])],
@@ -70,10 +64,6 @@ AC_ARG_ENABLE(atomic,
 	[enable_atomic=yes]
 	)
 
-AS_IF([test "x$enable_atomic" != xno],
-        [],
-	[AC_SUBST(atomic_cflags,-mno-atomic)])
-
 AC_ARG_ENABLE(float,
 	[AS_HELP_STRING([--disable-float],
 		[use software floating point in glibc @<:@--enable-float@:>@])],
@@ -81,6 +71,39 @@ AC_ARG_ENABLE(float,
 	[enable_float=yes]
 	)
 
+AC_DEFUN([MATCH_PATTERN], [echo "$1" | $GREP -qE "$2"])
+
+AC_DEFUN([GENERATE_EXTENSION],
+	[AS_IF([MATCH_PATTERN([$1], [^RV(32|64).*$2])],
+		[$3=yes],
+		[$3=no])]
+	)
+
+AC_DEFUN([PARSE_EXTENSIONS],
+	[GENERATE_EXTENSION([$1], A, enable_atomic)
+	 GENERATE_EXTENSION([$1], F, enable_float)]
+	)
+
+AC_DEFUN([PARSE_BASE_ARCH],
+	[AS_IF([MATCH_PATTERN([$1], [^RV32])],
+		AC_SUBST(XLEN, 32))
+	 AS_IF([MATCH_PATTERN([$1], [^RV64])],
+		AC_SUBST(XLEN, 64))]
+	)
+
+AC_ARG_WITH(arch,
+	[AS_HELP_STRING([--with-arch=RV64IMAFD],
+		[Sets the base RISC-V ISA, defaults to RV64IMAFD])],
+	[PARSE_BASE_ARCH([$withval])
+	 PARSE_EXTENSIONS([$withval])
+	 AC_SUBST(WITH_ARCH, --with-arch=$withval)],
+	[]
+	)
+
+AS_IF([test "x$enable_atomic" != xno],
+        [],
+	[AC_SUBST(atomic_cflags,-mno-atomic)])
+
 AS_IF([test "x$enable_float" != xno],
 	    [AC_SUBST(float_cflags,-mhard-float)dnl
 AC_SUBST(float_asflags,-mhard-float)dnl
-- 
cgit v1.1