tcg/s390: Use constant pool for cmpi

Also use CHI/CGHI for 16-bit signed constants.

Backports commit a534bb15f30ff7e420434b3e5746bcad595c5429 from qemu

qemu/tcg/s390/tcg-target.inc.c

@@ -39,9 +39,8 @@
 
 #define TCG_CT_CONST_S16   0x100
 #define TCG_CT_CONST_S32   0x200
-#define TCG_CT_CONST_U31   0x400
+#define TCG_CT_CONST_S33   0x400
-#define TCG_CT_CONST_S33   0x800
+#define TCG_CT_CONST_ZERO  0x800
-#define TCG_CT_CONST_ZERO  0x1000
 
 /* Several places within the instruction set 0 means "no register"
    rather than TCG_REG_R0.  */
@@ -80,6 +79,10 @@ typedef enum S390Opcode {
     RIL_CGFI    = 0xc20c,
     RIL_CLFI    = 0xc20f,
     RIL_CLGFI   = 0xc20e,
+    RIL_CLRL    = 0xc60f,
+    RIL_CLGRL   = 0xc60a,
+    RIL_CRL     = 0xc60d,
+    RIL_CGRL    = 0xc608,
     RIL_IIHF    = 0xc008,
     RIL_IILF    = 0xc009,
     RIL_LARL    = 0xc000,
@@ -102,6 +105,8 @@ typedef enum S390Opcode {
     RI_AGHI     = 0xa70b,
     RI_AHI      = 0xa70a,
     RI_BRC      = 0xa704,
+    RI_CHI      = 0xa70e,
+    RI_CGHI     = 0xa70f,
     RI_IIHH     = 0xa500,
     RI_IIHL     = 0xa501,
     RI_IILH     = 0xa502,
@@ -211,6 +216,8 @@ typedef enum S390Opcode {
     RXY_AG      = 0xe308,
     RXY_AY      = 0xe35a,
     RXY_CG      = 0xe320,
+    RXY_CLG     = 0xe321,
+    RXY_CLY     = 0xe355,
     RXY_CY      = 0xe359,
     RXY_LAY     = 0xe371,
     RXY_LB      = 0xe376,
@@ -429,20 +436,6 @@ static const char *target_parse_constraint(TCGArgConstraint *ct,
     case 'J':
         ct->ct |= TCG_CT_CONST_S32;
         break;
-    case 'C':
-        /* ??? We have no insight here into whether the comparison is
-           signed or unsigned.  The COMPARE IMMEDIATE insn uses a 32-bit
-           signed immediate, and the COMPARE LOGICAL IMMEDIATE insn uses
-           a 32-bit unsigned immediate.  If we were to use the (semi)
-           obvious "val == (int32_t)val" we would be enabling unsigned
-           comparisons vs very large numbers.  The only solution is to
-           take the intersection of the ranges.  */
-        /* ??? Another possible solution is to simply lie and allow all
-           constants here and force the out-of-range values into a temp
-           register in tgen_cmp when we have knowledge of the actual
-           comparison code in use.  */
-        ct->ct |= TCG_CT_CONST_U31;
-        break;
     case 'Z':
         ct->ct |= TCG_CT_CONST_ZERO;
         break;
@@ -473,8 +466,6 @@ static int tcg_target_const_match(tcg_target_long val, TCGType type,
         return val == (int32_t)val;
     } else if (ct & TCG_CT_CONST_S33) {
         return val >= -0xffffffffll && val <= 0xffffffffll;
-    } else if (ct & TCG_CT_CONST_U31) {
-        return val >= 0 && val <= 0x7fffffff;
     } else if (ct & TCG_CT_CONST_ZERO) {
         return val == 0;
     }
@@ -1097,6 +1088,8 @@ static int tgen_cmp(TCGContext *s, TCGType type, TCGCond c, TCGReg r1,
                     TCGArg c2, bool c2const, bool need_carry)
 {
     bool is_unsigned = is_unsigned_cond(c);
+    S390Opcode op;
+
     if (c2const) {
         if (c2 == 0) {
             if (!(is_unsigned && need_carry)) {
@@ -1107,44 +1100,67 @@ static int tgen_cmp(TCGContext *s, TCGType type, TCGCond c, TCGReg r1,
                 }
                 return tcg_cond_to_ltr_cond[c];
             }
-            /* If we only got here because of load-and-test,
+        }
-               and we couldn't use that, then we need to load
+
-               the constant into a register.  */
+        if (!is_unsigned && c2 == (int16_t)c2) {
-            if (!(s390_facilities & FACILITY_EXT_IMM)) {
+            op = (type == TCG_TYPE_I32 ? RI_CHI : RI_CGHI);
-                c2 = TCG_TMP0;
+            tcg_out_insn_RI(s, op, r1, c2);
-                tcg_out_movi(s, type, c2, 0);
+            goto exit;
-                goto do_reg;
+        }
+
+        if (s390_facilities & FACILITY_EXT_IMM) {
+            if (type == TCG_TYPE_I32) {
+                op = (is_unsigned ? RIL_CLFI : RIL_CFI);
+                tcg_out_insn_RIL(s, op, r1, c2);
+                goto exit;
+            } else if (c2 == (is_unsigned ? (uint32_t)c2 : (int32_t)c2)) {
+                op = (is_unsigned ? RIL_CLGFI : RIL_CGFI);
+                tcg_out_insn_RIL(s, op, r1, c2);
+                goto exit;
             }
         }
-        if (is_unsigned) {
+
+        /* Use the constant pool, but not for small constants.  */
+        if (maybe_out_small_movi(s, type, TCG_TMP0, c2)) {
+            c2 = TCG_TMP0;
+            /* fall through to reg-reg */
+        } else if (USE_REG_TB) {
             if (type == TCG_TYPE_I32) {
-                tcg_out_insn(s, RIL, CLFI, r1, c2);
+                op = (is_unsigned ? RXY_CLY : RXY_CY);
+                tcg_out_insn_RXY(s, op, r1, TCG_REG_TB, TCG_REG_NONE, 0);
+                new_pool_label(s, (uint32_t)c2, R_390_20, s->code_ptr - 2,
+                               4 - (intptr_t)s->code_gen_ptr);
             } else {
-                tcg_out_insn(s, RIL, CLGFI, r1, c2);
+                op = (is_unsigned ? RXY_CLG : RXY_CG);
+                tcg_out_insn_RXY(s, op, r1, TCG_REG_TB, TCG_REG_NONE, 0);
+                new_pool_label(s, c2, R_390_20, s->code_ptr - 2,
+                               -(intptr_t)s->code_gen_ptr);
             }
+            goto exit;
         } else {
             if (type == TCG_TYPE_I32) {
-                tcg_out_insn(s, RIL, CFI, r1, c2);
+                op = (is_unsigned ? RIL_CLRL : RIL_CRL);
+                tcg_out_insn_RIL(s, op, r1, 0);
+                new_pool_label(s, (uint32_t)c2, R_390_PC32DBL,
+                               s->code_ptr - 2, 2 + 4);
             } else {
-                tcg_out_insn(s, RIL, CGFI, r1, c2);
+                op = (is_unsigned ? RIL_CLGRL : RIL_CGRL);
-            }
+                tcg_out_insn_RIL(s, op, r1, 0);
-        }
+                new_pool_label(s, c2, R_390_PC32DBL, s->code_ptr - 2, 2);
-    } else {
-    do_reg:
-        if (is_unsigned) {
-            if (type == TCG_TYPE_I32) {
-                tcg_out_insn(s, RR, CLR, r1, c2);
-            } else {
-                tcg_out_insn(s, RRE, CLGR, r1, c2);
-            }
-        } else {
-            if (type == TCG_TYPE_I32) {
-                tcg_out_insn(s, RR, CR, r1, c2);
-            } else {
-                tcg_out_insn(s, RRE, CGR, r1, c2);
             }
+            goto exit;
         }
     }
+
+    if (type == TCG_TYPE_I32) {
+        op = (is_unsigned ? RR_CLR : RR_CR);
+        tcg_out_insn_RR(s, op, r1, c2);
+    } else {
+        op = (is_unsigned ? RRE_CLGR : RRE_CGR);
+        tcg_out_insn_RRE(s, op, r1, c2);
+    }
+
+ exit:
     return tcg_cond_to_s390_cond[c];
 }