tcg: Split rem requirement from div requirement

There are several hosts with only a "div" insn.  Remainder is computed
manually from the quotient and inputs.  We can do this generically.
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRichard Henderson <rth@twiddle.net>

tcg/aarch64/tcg-target.h

@@ -40,6 +40,7 @@ typedef enum {
 
 /* optional instructions */
 #define TCG_TARGET_HAS_div_i32          0
+#define TCG_TARGET_HAS_rem_i32          0
 #define TCG_TARGET_HAS_ext8s_i32        1
 #define TCG_TARGET_HAS_ext16s_i32       1
 #define TCG_TARGET_HAS_ext8u_i32        1
@@ -62,6 +63,7 @@ typedef enum {
 #define TCG_TARGET_HAS_muls2_i32        0
 
 #define TCG_TARGET_HAS_div_i64          0
+#define TCG_TARGET_HAS_rem_i64          0
 #define TCG_TARGET_HAS_ext8s_i64        1
 #define TCG_TARGET_HAS_ext16s_i64       1
 #define TCG_TARGET_HAS_ext32s_i64       1

tcg/arm/tcg-target.h

@@ -76,8 +76,10 @@ typedef enum {
 
 #ifdef __ARM_ARCH_EXT_IDIV__
 #define TCG_TARGET_HAS_div_i32          1
+#define TCG_TARGET_HAS_rem_i32          1
 #else
 #define TCG_TARGET_HAS_div_i32          0
+#define TCG_TARGET_HAS_rem_i32          0
 #endif
 
 extern bool tcg_target_deposit_valid(int ofs, int len);

tcg/hppa/tcg-target.h

@@ -85,6 +85,7 @@ typedef enum {
 
 /* optional instructions */
 #define TCG_TARGET_HAS_div_i32          0
+#define TCG_TARGET_HAS_rem_i32          0
 #define TCG_TARGET_HAS_rot_i32          1
 #define TCG_TARGET_HAS_ext8s_i32        1
 #define TCG_TARGET_HAS_ext16s_i32       1

tcg/ia64/tcg-target.h

@@ -104,7 +104,9 @@ typedef enum {
 
 /* optional instructions */
 #define TCG_TARGET_HAS_div_i32          0
+#define TCG_TARGET_HAS_rem_i32          0
 #define TCG_TARGET_HAS_div_i64          0
+#define TCG_TARGET_HAS_rem_i64          0
 #define TCG_TARGET_HAS_andc_i32         1
 #define TCG_TARGET_HAS_andc_i64         1
 #define TCG_TARGET_HAS_bswap16_i32      1

tcg/mips/tcg-target.h

@@ -79,6 +79,7 @@ typedef enum {
 
 /* optional instructions */
 #define TCG_TARGET_HAS_div_i32          1
+#define TCG_TARGET_HAS_rem_i32          1
 #define TCG_TARGET_HAS_not_i32          1
 #define TCG_TARGET_HAS_nor_i32          1
 #define TCG_TARGET_HAS_ext8s_i32        1

tcg/ppc/tcg-target.h

@@ -78,6 +78,7 @@ typedef enum {
 
 /* optional instructions */
 #define TCG_TARGET_HAS_div_i32          1
+#define TCG_TARGET_HAS_rem_i32          1
 #define TCG_TARGET_HAS_rot_i32          1
 #define TCG_TARGET_HAS_ext8s_i32        1
 #define TCG_TARGET_HAS_ext16s_i32       1

tcg/ppc64/tcg-target.h

@@ -76,6 +76,7 @@ typedef enum {
 
 /* optional instructions */
 #define TCG_TARGET_HAS_div_i32          1
+#define TCG_TARGET_HAS_rem_i32          1
 #define TCG_TARGET_HAS_rot_i32          1
 #define TCG_TARGET_HAS_ext8s_i32        1
 #define TCG_TARGET_HAS_ext16s_i32       1
@@ -96,6 +97,7 @@ typedef enum {
 #define TCG_TARGET_HAS_muls2_i32        0
 
 #define TCG_TARGET_HAS_div_i64          1
+#define TCG_TARGET_HAS_rem_i64          1
 #define TCG_TARGET_HAS_rot_i64          1
 #define TCG_TARGET_HAS_ext8s_i64        1
 #define TCG_TARGET_HAS_ext16s_i64       1

tcg/sparc/tcg-target.h

@@ -86,6 +86,7 @@ typedef enum {
 
 /* optional instructions */
 #define TCG_TARGET_HAS_div_i32		1
+#define TCG_TARGET_HAS_rem_i32		1
 #define TCG_TARGET_HAS_rot_i32          0
 #define TCG_TARGET_HAS_ext8s_i32        0
 #define TCG_TARGET_HAS_ext16s_i32       0
@@ -109,6 +110,7 @@ typedef enum {
 
 #if TCG_TARGET_REG_BITS == 64
 #define TCG_TARGET_HAS_div_i64          1
+#define TCG_TARGET_HAS_rem_i64          1
 #define TCG_TARGET_HAS_rot_i64          0
 #define TCG_TARGET_HAS_ext8s_i64        0
 #define TCG_TARGET_HAS_ext16s_i64       0

tcg/tcg-op.h

@@ -731,8 +731,14 @@ static inline void tcg_gen_div_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
 
 static inline void tcg_gen_rem_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
 {
-    if (TCG_TARGET_HAS_div_i32) {
+    if (TCG_TARGET_HAS_rem_i32) {
         tcg_gen_op3_i32(INDEX_op_rem_i32, ret, arg1, arg2);
+    } else if (TCG_TARGET_HAS_div_i32) {
+        TCGv_i32 t0 = tcg_temp_new_i32();
+        tcg_gen_op3_i32(INDEX_op_div_i32, t0, arg1, arg2);
+        tcg_gen_mul_i32(t0, t0, arg2);
+        tcg_gen_sub_i32(ret, arg1, t0);
+        tcg_temp_free_i32(t0);
     } else if (TCG_TARGET_HAS_div2_i32) {
         TCGv_i32 t0 = tcg_temp_new_i32();
         tcg_gen_sari_i32(t0, arg1, 31);
@@ -769,8 +775,14 @@ static inline void tcg_gen_divu_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
 
 static inline void tcg_gen_remu_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
 {
-    if (TCG_TARGET_HAS_div_i32) {
+    if (TCG_TARGET_HAS_rem_i32) {
         tcg_gen_op3_i32(INDEX_op_remu_i32, ret, arg1, arg2);
+    } else if (TCG_TARGET_HAS_div_i32) {
+        TCGv_i32 t0 = tcg_temp_new_i32();
+        tcg_gen_op3_i32(INDEX_op_divu_i32, t0, arg1, arg2);
+        tcg_gen_mul_i32(t0, t0, arg2);
+        tcg_gen_sub_i32(ret, arg1, t0);
+        tcg_temp_free_i32(t0);
     } else if (TCG_TARGET_HAS_div2_i32) {
         TCGv_i32 t0 = tcg_temp_new_i32();
         tcg_gen_movi_i32(t0, 0);
@@ -1361,8 +1373,14 @@ static inline void tcg_gen_div_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
 
 static inline void tcg_gen_rem_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
 {
-    if (TCG_TARGET_HAS_div_i64) {
+    if (TCG_TARGET_HAS_rem_i64) {
         tcg_gen_op3_i64(INDEX_op_rem_i64, ret, arg1, arg2);
+    } else if (TCG_TARGET_HAS_div_i64) {
+        TCGv_i64 t0 = tcg_temp_new_i64();
+        tcg_gen_op3_i64(INDEX_op_div_i64, t0, arg1, arg2);
+        tcg_gen_mul_i64(t0, t0, arg2);
+        tcg_gen_sub_i64(ret, arg1, t0);
+        tcg_temp_free_i64(t0);
     } else if (TCG_TARGET_HAS_div2_i64) {
         TCGv_i64 t0 = tcg_temp_new_i64();
         tcg_gen_sari_i64(t0, arg1, 63);
@@ -1399,8 +1417,14 @@ static inline void tcg_gen_divu_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
 
 static inline void tcg_gen_remu_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
 {
-    if (TCG_TARGET_HAS_div_i64) {
+    if (TCG_TARGET_HAS_rem_i64) {
         tcg_gen_op3_i64(INDEX_op_remu_i64, ret, arg1, arg2);
+    } else if (TCG_TARGET_HAS_div_i64) {
+        TCGv_i64 t0 = tcg_temp_new_i64();
+        tcg_gen_op3_i64(INDEX_op_divu_i64, t0, arg1, arg2);
+        tcg_gen_mul_i64(t0, t0, arg2);
+        tcg_gen_sub_i64(ret, arg1, t0);
+        tcg_temp_free_i64(t0);
     } else if (TCG_TARGET_HAS_div2_i64) {
         TCGv_i64 t0 = tcg_temp_new_i64();
         tcg_gen_movi_i64(t0, 0);

tcg/tcg-opc.h

@@ -66,8 +66,8 @@ DEF(sub_i32, 1, 2, 0, 0)
 DEF(mul_i32, 1, 2, 0, 0)
 DEF(div_i32, 1, 2, 0, IMPL(TCG_TARGET_HAS_div_i32))
 DEF(divu_i32, 1, 2, 0, IMPL(TCG_TARGET_HAS_div_i32))
-DEF(rem_i32, 1, 2, 0, IMPL(TCG_TARGET_HAS_div_i32))
-DEF(remu_i32, 1, 2, 0, IMPL(TCG_TARGET_HAS_div_i32))
+DEF(rem_i32, 1, 2, 0, IMPL(TCG_TARGET_HAS_rem_i32))
+DEF(remu_i32, 1, 2, 0, IMPL(TCG_TARGET_HAS_rem_i32))
 DEF(div2_i32, 2, 3, 0, IMPL(TCG_TARGET_HAS_div2_i32))
 DEF(divu2_i32, 2, 3, 0, IMPL(TCG_TARGET_HAS_div2_i32))
 DEF(and_i32, 1, 2, 0, 0)
@@ -126,8 +126,8 @@ DEF(sub_i64, 1, 2, 0, IMPL64)
 DEF(mul_i64, 1, 2, 0, IMPL64)
 DEF(div_i64, 1, 2, 0, IMPL64 | IMPL(TCG_TARGET_HAS_div_i64))
 DEF(divu_i64, 1, 2, 0, IMPL64 | IMPL(TCG_TARGET_HAS_div_i64))
-DEF(rem_i64, 1, 2, 0, IMPL64 | IMPL(TCG_TARGET_HAS_div_i64))
-DEF(remu_i64, 1, 2, 0, IMPL64 | IMPL(TCG_TARGET_HAS_div_i64))
+DEF(rem_i64, 1, 2, 0, IMPL64 | IMPL(TCG_TARGET_HAS_rem_i64))
+DEF(remu_i64, 1, 2, 0, IMPL64 | IMPL(TCG_TARGET_HAS_rem_i64))
 DEF(div2_i64, 2, 3, 0, IMPL64 | IMPL(TCG_TARGET_HAS_div2_i64))
 DEF(divu2_i64, 2, 3, 0, IMPL64 | IMPL(TCG_TARGET_HAS_div2_i64))
 DEF(and_i64, 1, 2, 0, IMPL64)

tcg/tcg.h

@@ -60,6 +60,7 @@ typedef uint64_t TCGRegSet;
 #if TCG_TARGET_REG_BITS == 32
 /* Turn some undef macros into false macros.  */
 #define TCG_TARGET_HAS_div_i64          0
+#define TCG_TARGET_HAS_rem_i64          0
 #define TCG_TARGET_HAS_div2_i64         0
 #define TCG_TARGET_HAS_rot_i64          0
 #define TCG_TARGET_HAS_ext8s_i64        0
@@ -102,11 +103,13 @@ typedef uint64_t TCGRegSet;
 #define TCG_TARGET_HAS_div2_i32         0
 #elif defined(TCG_TARGET_HAS_div2_i32)
 #define TCG_TARGET_HAS_div_i32          0
+#define TCG_TARGET_HAS_rem_i32          0
 #endif
 #if defined(TCG_TARGET_HAS_div_i64)
 #define TCG_TARGET_HAS_div2_i64         0
 #elif defined(TCG_TARGET_HAS_div2_i64)
 #define TCG_TARGET_HAS_div_i64          0
+#define TCG_TARGET_HAS_rem_i64          0
 #endif
 
 typedef enum TCGOpcode {

tcg/tci/tcg-target.h

@@ -59,9 +59,8 @@
 
 #define TCG_TARGET_HAS_bswap16_i32      1
 #define TCG_TARGET_HAS_bswap32_i32      1
-/* Not more than one of the next two defines must be 1. */
 #define TCG_TARGET_HAS_div_i32          1
-#define TCG_TARGET_HAS_div2_i32         0
+#define TCG_TARGET_HAS_rem_i32          1
 #define TCG_TARGET_HAS_ext8s_i32        1
 #define TCG_TARGET_HAS_ext16s_i32       1
 #define TCG_TARGET_HAS_ext8u_i32        1
@@ -83,9 +82,8 @@
 #define TCG_TARGET_HAS_bswap32_i64      1
 #define TCG_TARGET_HAS_bswap64_i64      1
 #define TCG_TARGET_HAS_deposit_i64      1
-/* Not more than one of the next two defines must be 1. */
 #define TCG_TARGET_HAS_div_i64          0
-#define TCG_TARGET_HAS_div2_i64         0
+#define TCG_TARGET_HAS_rem_i64          0
 #define TCG_TARGET_HAS_ext8s_i64        1
 #define TCG_TARGET_HAS_ext16s_i64       1
 #define TCG_TARGET_HAS_ext32s_i64       1