VM: Implement ASM_ADD, ASM_SUB, and ASM_MUL for ARM processors.

[bpt/guile.git] / libguile / vm-i-scheme.c

diff --git a/libguile/vm-i-scheme.c b/libguile/vm-i-scheme.c
index d459e3e..a703aed 100644 (file)
--- a/libguile/vm-i-scheme.c
+++ b/libguile/vm-i-scheme.c
@@ -309,6 +309,52 @@ VM_DEFINE_FUNCTION (149, ge, "ge?", 2)
 
 #endif
 
+#if SCM_GNUC_PREREQ (4, 5) && defined __arm__
+
+# define ASM_ADD(x, y)                                                 \
+    if (SCM_LIKELY (SCM_I_INUMP (x) && SCM_I_INUMP (y)))               \
+      {                                                                        \
+       asm volatile goto ("adds r0, %0, %1; bvs %l[slow_add]; "        \
+                          "str r0, [%[vsp]]\n"                         \
+                          : /* no outputs */                           \
+                          : "r" (x), "r" (y - scm_tc2_int),            \
+                            [vsp] "r" (sp)                             \
+                          : "r0", "memory", "cc"                       \
+                          : slow_add);                                 \
+       NEXT;                                                           \
+      }                                                                        \
+  slow_add:                                                            \
+    do { } while (0)
+
+# define ASM_SUB(x, y)                                                 \
+    if (SCM_LIKELY (SCM_I_INUMP (x) && SCM_I_INUMP (y)))               \
+      {                                                                        \
+       asm volatile goto ("subs r0, %0, %1; bvs %l[slow_sub]; "        \
+                          "str r0, [%[vsp]]\n"                         \
+                          : /* no outputs */                           \
+                          : "r" (x), "r" (y - scm_tc2_int),            \
+                            [vsp] "r" (sp)                             \
+                          : "r0", "memory", "cc"                       \
+                          : slow_sub);                                 \
+       NEXT;                                                           \
+      }                                                                        \
+  slow_sub:                                                            \
+    do { } while (0)
+
+# define ASM_MUL(x, y)                                                 \
+    if (SCM_LIKELY (SCM_I_INUMP (x) && SCM_I_INUMP (y)))               \
+      {                                                                        \
+       scm_t_signed_bits rlo, rhi;                                     \
+       asm ("smull %0, %1, %2, %3\n"                                   \
+            : "=r" (rlo), "=r" (rhi)                                   \
+            : "r" (SCM_UNPACK (x) - scm_tc2_int),                      \
+              "r" (SCM_I_INUM (y)));                                   \
+       if (SCM_LIKELY (SCM_SRS (rlo, 31) == rhi))                      \
+         RETURN (SCM_PACK (rlo + scm_tc2_int));                        \
+      }                                                                        \
+    do { } while (0)
+
+#endif
 
 VM_DEFINE_FUNCTION (150, add, "add", 2)
 {