tcg: add div/rem 32-bit helpers

Some targets like ARM would benefit to use 32-bit helpers for
div/rem/divu/remu.

Create a #define for div2 so that targets can select between
div, div2 and helper implementation. Use the helper version if none
of the #define are present.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

tcg-runtime.c

@@ -25,6 +25,30 @@
 
 #include "tcg/tcg-runtime.h"
 
+/* 32-bit helpers */
+
+int32_t tcg_helper_div_i32(int32_t arg1, int32_t arg2)
+{
+    return arg1 / arg2;
+}
+
+int32_t tcg_helper_rem_i32(int32_t arg1, int32_t arg2)
+{
+    return arg1 % arg2;
+}
+
+uint32_t tcg_helper_divu_i32(uint32_t arg1, uint32_t arg2)
+{
+    return arg1 / arg2;
+}
+
+uint32_t tcg_helper_remu_i32(uint32_t arg1, uint32_t arg2)
+{
+    return arg1 % arg2;
+}
+
+/* 64-bit helpers */
+
 int64_t tcg_helper_shl_i64(int64_t arg1, int64_t arg2)
 {
     return arg1 << arg2;

tcg/arm/tcg-target.h

@@ -56,6 +56,7 @@ enum {
 #define TCG_TARGET_CALL_STACK_OFFSET	0
 
 /* optional instructions */
+#define TCG_TARGET_HAS_div2_i32
 #define TCG_TARGET_HAS_ext8s_i32
 #define TCG_TARGET_HAS_ext16s_i32
 // #define TCG_TARGET_HAS_ext8u_i32

tcg/hppa/tcg-target.h

@@ -75,6 +75,7 @@ enum {
 #define TCG_TARGET_STACK_GROWSUP
 
 /* optional instructions */
+#define TCG_TARGET_HAS_div2_i32
 //#define TCG_TARGET_HAS_ext8s_i32
 //#define TCG_TARGET_HAS_ext16s_i32
 //#define TCG_TARGET_HAS_bswap16_i32

tcg/i386/tcg-target.h

@@ -45,6 +45,7 @@ enum {
 #define TCG_TARGET_CALL_STACK_OFFSET 0
 
 /* optional instructions */
+#define TCG_TARGET_HAS_div2_i32
 #define TCG_TARGET_HAS_rot_i32
 #define TCG_TARGET_HAS_ext8s_i32
 #define TCG_TARGET_HAS_ext16s_i32

tcg/tcg-op.h

@@ -364,6 +364,19 @@ static inline void tcg_gen_helperN(void *func, int flags, int sizemask,
     tcg_temp_free_ptr(fn);
 }
 
+/* FIXME: Should this be pure?  */
+static inline void tcg_gen_helper32(void *func, TCGv_i32 ret,
+                                    TCGv_i32 a, TCGv_i32 b)
+{
+    TCGv_ptr fn;
+    TCGArg args[2];
+    fn = tcg_const_ptr((tcg_target_long)func);
+    args[0] = GET_TCGV_I32(a);
+    args[1] = GET_TCGV_I32(b);
+    tcg_gen_callN(&tcg_ctx, fn, 0, 0, GET_TCGV_I32(ret), 2, args);
+    tcg_temp_free_ptr(fn);
+}
+
 /* FIXME: Should this be pure?  */
 static inline void tcg_gen_helper64(void *func, TCGv_i64 ret,
                                     TCGv_i64 a, TCGv_i64 b)
@@ -635,7 +648,7 @@ static inline void tcg_gen_remu_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
 {
     tcg_gen_op3_i32(INDEX_op_remu_i32, ret, arg1, arg2);
 }
-#else
+#elif defined(TCG_TARGET_HAS_div2_i32)
 static inline void tcg_gen_div_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
 {
     TCGv_i32 t0;
@@ -671,6 +684,26 @@ static inline void tcg_gen_remu_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
     tcg_gen_op5_i32(INDEX_op_divu2_i32, t0, ret, arg1, t0, arg2);
     tcg_temp_free_i32(t0);
 }
+#else
+static inline void tcg_gen_div_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
+{
+    tcg_gen_helper32(tcg_helper_div_i32, ret, arg1, arg2);
+}
+
+static inline void tcg_gen_rem_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
+{
+    tcg_gen_helper32(tcg_helper_rem_i32, ret, arg1, arg2);
+}
+
+static inline void tcg_gen_divu_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
+{
+    tcg_gen_helper32(tcg_helper_divu_i32, ret, arg1, arg2);
+}
+
+static inline void tcg_gen_remu_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
+{
+    tcg_gen_helper32(tcg_helper_remu_i32, ret, arg1, arg2);
+}
 #endif
 
 #if TCG_TARGET_REG_BITS == 32
@@ -1135,7 +1168,7 @@ static inline void tcg_gen_remu_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
 {
     tcg_gen_op3_i64(INDEX_op_remu_i64, ret, arg1, arg2);
 }
-#else
+#elif defined(TCG_TARGET_HAS_div2_i64)
 static inline void tcg_gen_div_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
 {
     TCGv_i64 t0;
@@ -1171,6 +1204,26 @@ static inline void tcg_gen_remu_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
     tcg_gen_op5_i64(INDEX_op_divu2_i64, t0, ret, arg1, t0, arg2);
     tcg_temp_free_i64(t0);
 }
+#else
+static inline void tcg_gen_div_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
+{
+    tcg_gen_helper64(tcg_helper_div_i64, ret, arg1, arg2);
+}
+
+static inline void tcg_gen_rem_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
+{
+    tcg_gen_helper64(tcg_helper_rem_i64, ret, arg1, arg2);
+}
+
+static inline void tcg_gen_divu_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
+{
+    tcg_gen_helper64(tcg_helper_divu_i64, ret, arg1, arg2);
+}
+
+static inline void tcg_gen_remu_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
+{
+    tcg_gen_helper64(tcg_helper_remu_i64, ret, arg1, arg2);
+}
 #endif
 
 #endif

tcg/tcg-runtime.h

@@ -2,6 +2,11 @@
 #define TCG_RUNTIME_H
 
 /* tcg-runtime.c */
+int32_t tcg_helper_div_i32(int32_t arg1, int32_t arg2);
+int32_t tcg_helper_rem_i32(int32_t arg1, int32_t arg2);
+uint32_t tcg_helper_divu_i32(uint32_t arg1, uint32_t arg2);
+uint32_t tcg_helper_remu_i32(uint32_t arg1, uint32_t arg2);
+
 int64_t tcg_helper_shl_i64(int64_t arg1, int64_t arg2);
 int64_t tcg_helper_shr_i64(int64_t arg1, int64_t arg2);
 int64_t tcg_helper_sar_i64(int64_t arg1, int64_t arg2);

tcg/x86_64/tcg-target.h

@@ -56,6 +56,8 @@ enum {
 #define TCG_TARGET_CALL_STACK_OFFSET 0
 
 /* optional instructions */
+#define TCG_TARGET_HAS_div2_i32
+#define TCG_TARGET_HAS_div2_i64
 #define TCG_TARGET_HAS_bswap16_i32
 #define TCG_TARGET_HAS_bswap16_i64
 #define TCG_TARGET_HAS_bswap32_i32