MSP430: Add -fno-exceptions multilib

ChangeLog:

2019-12-11  Jozef Lawrynowicz  <jozef.l@mittosystems.com>

	* config-ml.in (msp430-*-*): Support --disable-no-exceptions configure
	flag.

gcc/ChangeLog:

2019-12-11  Jozef Lawrynowicz  <jozef.l@mittosystems.com>

	* config/msp430/msp430.h (STARTFILE_SPEC) [!fexceptions]: Use
	crtbegin_no_eh.o if building for the C language.
	[fno-exceptions]: Use crtbegin_no_eh.o if building for any language
	except C.
	(ENDFILE_SPEC) [!fexceptions]: Use crtend_no_eh.o if building for 
	the C language.
	[fno-exceptions]: Use crtend_no_eh.o if building for any language
	except C.
	* config/msp430/t-msp430: Add -fno-exceptions multilib.
	* doc/install.texi: Document --disable-no-exceptions multilib configure
	option.
	* doc/sourcebuild.texi: Document exceptions_enabled effective target.

gcc/testsuite/ChangeLog:

2019-12-11  Jozef Lawrynowicz  <jozef.l@mittosystems.com>

	* lib/gcc-dg.exp: Add dg-prune messages for when exception handling is
	disabled.
	* lib/target-supports.exp (check_effective_target_exceptions_enabled):
	New.

libgcc/ChangeLog:

2019-12-11  Jozef Lawrynowicz  <jozef.l@mittosystems.com>

	* config.host: Add crt{begin,end}_no_eh.o to "extra_parts".
	* config.host (msp430*-*-elf): Add crt{begin,end}_no_eh.o to
	"extra_parts".

From-SVN: r279246

8 files changed, 73 insertions, 6 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 747b04d..7772383 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,18 @@
+2019-12-11  Jozef Lawrynowicz  <jozef.l@mittosystems.com>
+
+	* config/msp430/msp430.h (STARTFILE_SPEC) [!fexceptions]: Use
+	crtbegin_no_eh.o if building for the C language.
+	[fno-exceptions]: Use crtbegin_no_eh.o if building for any language
+	except C.
+	(ENDFILE_SPEC) [!fexceptions]: Use crtend_no_eh.o if building for 
+	the C language.
+	[fno-exceptions]: Use crtend_no_eh.o if building for any language
+	except C.
+	* config/msp430/t-msp430: Add -fno-exceptions multilib.
+	* doc/install.texi: Document --disable-no-exceptions multilib configure
+	option.
+	* doc/sourcebuild.texi: Document exceptions_enabled effective target.
+
 2019-12-11  David Malcolm  <dmalcolm@redhat.com>
 
 	* pretty-print.c (pretty_printer::pretty_printer): New copy-ctor.
diff --git a/gcc/config/msp430/msp430.h b/gcc/config/msp430/msp430.h
index 0ea6b0a..7b94918 100644
--- a/gcc/config/msp430/msp430.h
+++ b/gcc/config/msp430/msp430.h
@@ -44,13 +44,20 @@ extern bool msp430x;
     }						\
   while (0)
 
+/* For the "c" language where exceptions are implicitly disabled, use
+   crt*_no_eh.o unless -fexceptions is passed.  For other languages, only use
+   crt*_no_eh.o if -fno-exceptions is explicitly passed.  */
 #undef  STARTFILE_SPEC
 #define STARTFILE_SPEC "%{pg:gcrt0.o%s}" \
-  "%{!pg:%{minrt:crt0-minrt.o%s}%{!minrt:crt0.o%s}} %{!minrt:crtbegin.o%s}"
+  "%{!pg:%{minrt:crt0-minrt.o%s}%{!minrt:crt0.o%s}} " \
+  "%{!minrt:%{,c:%{!fexceptions:crtbegin_no_eh.o%s; :crtbegin.o%s}; " \
+    ":%{fno-exceptions:crtbegin_no_eh.o%s; :crtbegin.o%s}}}"
 
 /* -lgcc is included because crtend.o needs __mspabi_func_epilog_1.  */
 #undef  ENDFILE_SPEC
-#define ENDFILE_SPEC "%{!minrt:crtend.o%s} " \
+#define ENDFILE_SPEC \
+  "%{!minrt:%{,c:%{!fexceptions:crtend_no_eh.o%s; :crtend.o%s}; " \
+    ":%{fno-exceptions:crtend_no_eh.o%s; :crtend.o%s}}} " \
   "%{minrt:%:if-exists(crtn-minrt.o%s)}%{!minrt:%:if-exists(crtn.o%s)} -lgcc"
 
 #define ASM_SPEC "-mP " /* Enable polymorphic instructions.  */ \
diff --git a/gcc/config/msp430/t-msp430 b/gcc/config/msp430/t-msp430
index f8ba775..e180ce3 100644
--- a/gcc/config/msp430/t-msp430
+++ b/gcc/config/msp430/t-msp430
@@ -28,8 +28,8 @@ msp430-devices.o: $(srcdir)/config/msp430/msp430-devices.c \
 
 # Enable multilibs:
 
-MULTILIB_OPTIONS    = mcpu=msp430 mlarge  mdata-region=none
-MULTILIB_DIRNAMES   = 430	   large  full-memory-range
+MULTILIB_OPTIONS    = mcpu=msp430 mlarge  mdata-region=none fno-exceptions
+MULTILIB_DIRNAMES   = 430	   large  full-memory-range no-exceptions
 
 # Match -mcpu=430
 MULTILIB_MATCHES    = mcpu?msp430=mcpu?430
@@ -41,9 +41,10 @@ MULTILIB_MATCHES   += mdata-region?none=mdata-region?either
 # hard-coded data here, because DRIVER_SELF_SPECS will place the correct
 # -mcpu option for a given mcu onto the command line.
 
-MULTILIB_REQUIRED = mcpu=msp430
-MULTILIB_REQUIRED += mlarge
+MULTILIB_REQUIRED =		    mcpu=msp430		       mlarge
+MULTILIB_REQUIRED += fno-exceptions mcpu=msp430/fno-exceptions mlarge/fno-exceptions
 MULTILIB_REQUIRED += mlarge/mdata-region=none
+MULTILIB_REQUIRED += mlarge/mdata-region=none/fno-exceptions
 
 
 MULTILIB_EXTRA_OPTS =
diff --git a/gcc/doc/install.texi b/gcc/doc/install.texi
index 80b4781..19d649c 100644
--- a/gcc/doc/install.texi
+++ b/gcc/doc/install.texi
@@ -1086,6 +1086,9 @@ softfloat, m68881, m68000, m68020.
 @item mips*-*-*
 single-float, biendian, softfloat.
 
+@item msp430-*-*
+no-exceptions
+
 @item powerpc*-*-*, rs6000*-*-*
 aix64, pthread, softfloat, powercpu, powerpccpu, powerpcos, biendian,
 sysv, aix.
diff --git a/gcc/doc/sourcebuild.texi b/gcc/doc/sourcebuild.texi
index 3950c82..85573a4 100644
--- a/gcc/doc/sourcebuild.texi
+++ b/gcc/doc/sourcebuild.texi
@@ -2274,6 +2274,10 @@ Target has packed layout of structure members by default.
 @item exceptions
 Target supports exceptions.
 
+@item exceptions_enabled
+Target supports exceptions and they are enabled in the current
+testing configuration.
+
 @item fgraphite
 Target supports Graphite optimizations.
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 0c22a9c..57d2a11 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2019-12-11  Jozef Lawrynowicz  <jozef.l@mittosystems.com>
+
+	* lib/gcc-dg.exp: Add dg-prune messages for when exception handling is
+	disabled.
+	* lib/target-supports.exp (check_effective_target_exceptions_enabled):
+	New.
+
 2019-12-11  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/92869
diff --git a/gcc/testsuite/lib/gcc-dg.exp b/gcc/testsuite/lib/gcc-dg.exp
index 1df645e..7396daa 100644
--- a/gcc/testsuite/lib/gcc-dg.exp
+++ b/gcc/testsuite/lib/gcc-dg.exp
@@ -417,6 +417,18 @@ proc gcc-dg-prune { system text } {
 	return "::unsupported::large return values"
     }
 
+    # If exceptions are disabled, mark tests expecting exceptions to be enabled
+    # as unsupported.
+    if { ![check_effective_target_exceptions_enabled] } {
+	if [regexp "(^|\n)\[^\n\]*: error: exception handling disabled" $text] {
+	    return "::unsupported::exception handling disabled"
+	}
+
+	if [regexp "(^|\n)\[^\n\]*: error: #error .__cpp_exceptions." $text] {
+	    return "::unsupported::exception handling disabled"
+	}
+    }
+
     return $text
 }
 
diff --git a/gcc/testsuite/lib/target-supports.exp b/gcc/testsuite/lib/target-supports.exp
index 5b4cc02..80e9d67 100644
--- a/gcc/testsuite/lib/target-supports.exp
+++ b/gcc/testsuite/lib/target-supports.exp
@@ -8990,6 +8990,24 @@ proc check_effective_target_exceptions {} {
     return 1
 }
 
+# Used to check if the testing configuration supports exceptions.
+# Returns 0 if exceptions are unsupported or disabled (e.g. by passing
+# -fno-exceptions). Returns 1 if exceptions are enabled.
+proc check_effective_target_exceptions_enabled {} {
+    return [check_cached_effective_target exceptions_enabled {
+	if { [check_effective_target_exceptions] } {
+	    return [check_no_compiler_messages exceptions_enabled assembly {
+		void foo (void)
+		{
+		    throw 1;
+		}
+	    }]
+	} else {
+	    # If exceptions aren't supported, then they're not enabled.
+	    return 0
+	}
+    }]
+}
 
 proc check_effective_target_tiny {} {
     return [check_cached_effective_target tiny {