Handle alignment fault fixups in libc rather than in the kernel.

lib/libc/sparc64/sys/Makefile.inc

@@ -2,6 +2,7 @@
 
 SRCS+=	__sparc_sigtramp_setup.c \
 	__sparc_utrap.c \
+	__sparc_utrap_align.c \
 	__sparc_utrap_emul.c \
 	__sparc_utrap_fp_disabled.S \
 	__sparc_utrap_gen.S \

lib/libc/sparc64/sys/__sparc_utrap.c

@@ -91,6 +91,7 @@ __sparc_utrap(struct utrapframe *uf)
 		sig = __emul_insn(uf);
 		break;
 	case UT_MEM_ADDRESS_NOT_ALIGNED:
+		sig = __unaligned_fixup(uf);
 		break;
 	default:
 		break;

lib/libc/sparc64/sys/__sparc_utrap_align.c

@@ -0,0 +1,117 @@
+/*-
+ * Copyright (c) 2002 Jake Burkholder.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <machine/cpufunc.h>
+#include <machine/instr.h>
+
+#include <signal.h>
+
+#include "__sparc_utrap_private.h"
+
+static u_long
+__unaligned_load(u_char *p, int size)
+{
+	u_long val;
+	int i;
+
+	val = 0;
+	for (i = 0; i < size; i++)
+		val = (val << 8) | p[i];
+	return (val);
+}
+
+static void
+__unaligned_store(u_char *p, u_long val, int size)
+{
+	int i;
+
+	for (i = 0; i < size; i++)
+		p[i] = val >> (i * 8);
+}
+
+int
+__unaligned_fixup(struct utrapframe *uf)
+{
+	u_char *addr;
+	u_long val;
+	u_int insn;
+	int sig;
+
+	sig = 0;
+	addr = (u_char *)uf->uf_sfar;
+	insn = *(u_int *)uf->uf_pc;
+	flushw();
+	switch (IF_OP(insn)) {
+	case IOP_LDST:
+		switch (IF_F3_OP3(insn)) {
+		case INS3_LDUH:
+			val = __unaligned_load(addr, 2);
+			__emul_store_reg(uf, IF_F3_RD(insn), val);
+			break;
+		case INS3_LDUW:
+			val = __unaligned_load(addr, 4);
+			__emul_store_reg(uf, IF_F3_RD(insn), val);
+			break;
+		case INS3_LDX:
+			val = __unaligned_load(addr, 8);
+			__emul_store_reg(uf, IF_F3_RD(insn), val);
+			break;
+		case INS3_LDSH:
+			val = __unaligned_load(addr, 2);
+			__emul_store_reg(uf, IF_F3_RD(insn),
+			    IF_SEXT(val, 16));
+			break;
+		case INS3_LDSW:
+			val = __unaligned_load(addr, 4);
+			__emul_store_reg(uf, IF_F3_RD(insn),
+			    IF_SEXT(val, 32));
+			break;
+		case INS3_STH:
+			val = __emul_fetch_reg(uf, IF_F3_RD(insn));
+			__unaligned_store(addr, val, 2);
+			break;
+		case INS3_STW:
+			val = __emul_fetch_reg(uf, IF_F3_RD(insn));
+			__unaligned_store(addr, val, 4);
+			break;
+		case INS3_STX:
+			val = __emul_fetch_reg(uf, IF_F3_RD(insn));
+			__unaligned_store(addr, val, 8);
+			break;
+		default:
+			sig = SIGILL;
+			break;
+		}
+		break;
+	default:
+		sig = SIGILL;
+		break;
+	}
+	return (sig);
+}

lib/libc/sparc64/sys/__sparc_utrap_private.h

@@ -55,6 +55,7 @@ u_long __emul_fetch_reg(struct utrapframe *uf, int reg);
 void __emul_store_reg(struct utrapframe *uf, int reg, u_long val);
 u_long __emul_f3_op2(struct utrapframe *uf, u_int insn);
 u_long __emul_f3_memop_addr(struct utrapframe *uf, u_int insn);
+int __unaligned_fixup(struct utrapframe *uf);
 
 void __sparc_utrap(struct utrapframe *);
 

lib/libc/sparc64/sys/__sparc_utrap_setup.c

@@ -41,9 +41,7 @@ static const struct sparc_utrap_args ua[] = {
 	{ UT_FP_EXCEPTION_IEEE_754, __sparc_utrap_gen, NULL, NULL, NULL },
 	{ UT_FP_EXCEPTION_OTHER, __sparc_utrap_gen, NULL, NULL, NULL },
 	{ UT_ILLEGAL_INSTRUCTION, __sparc_utrap_gen, NULL, NULL, NULL },
-#if 0
 	{ UT_MEM_ADDRESS_NOT_ALIGNED, __sparc_utrap_gen, NULL, NULL, NULL },
-#endif
 };
 
 static const struct sparc_utrap_install_args uia[] = {