Fix vfp:

 - We should check is_d32 to see howmany registers we have
 - In vfp_restore mark vfpscr as an output register

Without the second part it appears we can return the incorrect value from
vfp_bounce if the VFP condition flags are set as it may override the
register holding the return value.

1 files changed, 15 insertions, 16 deletions

diff --git a/sys/arm/arm/vfp.c b/sys/arm/arm/vfp.c
index 212e4c3..b9dce13 100644
--- a/sys/arm/arm/vfp.c
+++ b/sys/arm/arm/vfp.c
@@ -202,21 +202,20 @@ vfp_restore(struct vfp_state *vfpsave)
 	 * form ldcl<c>, and similar for stcleq.
 	 */
 #ifdef __clang__
-#define	ldcleq	"ldcleq"
-#define	stcleq	"stcleq"
+#define	ldclne	"ldclne"
+#define	stclne	"stclne"
 #else
-#define	ldcleq	"ldceql"
-#define	stcleq	"stceql"
+#define	ldclne	"ldcnel"
+#define	stclne	"stcnel"
 #endif
 	if (vfpsave) {
-		__asm __volatile("ldc	p10, c0, [%0], #128\n" /* d0-d15 */
-			"cmp	%0, #0\n"		/* -D16 or -D32? */
-			ldcleq"	p11, c0, [%0], #128\n"	/* d16-d31 */
-			"addne	%0, %0, #128\n"		/* skip missing regs */
-			"ldr	%1, [%0]\n"		/* set old vfpscr */
-			"mcr	p10, 7, %1, cr1, c0, 0\n"
-				:: "r" (vfpsave), "r" (vfpscr), "r" (is_d32)
-				: "cc");
+		__asm __volatile("ldc	p10, c0, [%1], #128\n" /* d0-d15 */
+			"cmp	%2, #0\n"		/* -D16 or -D32? */
+			ldclne"	p11, c0, [%1], #128\n"	/* d16-d31 */
+			"addeq	%1, %1, #128\n"		/* skip missing regs */
+			"ldr	%0, [%1]\n"		/* set old vfpscr */
+			"mcr	p10, 7, %0, cr1, c0, 0\n"
+			: "=&r" (vfpscr) : "r" (vfpsave), "r" (is_d32) : "cc");
 		PCPU_SET(vfpcthread, PCPU_GET(curthread));
 	}
 }
@@ -238,12 +237,12 @@ vfp_store(struct vfp_state *vfpsave)
 	tmp = fmrx(VFPEXC);		/* Is the vfp enabled? */
 	if (vfpsave && tmp & VFPEXC_EN) {
 		__asm __volatile("stc	p11, c0, [%1], #128\n" /* d0-d15 */
-			"cmp	%0, #0\n"		/* -D16 or -D32? */
-			stcleq"	p11, c0, [%1], #128\n"	/* d16-d31 */
-			"addne	%1, %1, #128\n"		/* skip missing regs */
+			"cmp	%2, #0\n"		/* -D16 or -D32? */
+			stclne"	p11, c0, [%1], #128\n"	/* d16-d31 */
+			"addeq	%1, %1, #128\n"		/* skip missing regs */
 			"mrc	p10, 7, %0, cr1, c0, 0\n" /* fmxr(VFPSCR) */
 			"str	%0, [%1]\n"		/* save vfpscr */
-			:  "=&r" (vfpscr) : "r" (vfpsave), "r" (is_d32) : "cc");
+			: "=&r" (vfpscr) : "r" (vfpsave), "r" (is_d32) : "cc");
 	}
 #undef ldcleq
 #undef stcleq