tcg/ppc: Use the Set Boolean Extension

The SETBC family of instructions requires exactly two insns for
all comparisions, saving 0-3 insns per (neg)setcond.

Tested-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

tcg/ppc/tcg-target.c.inc

@@ -447,6 +447,11 @@ static bool tcg_target_const_match(int64_t val, TCGType type, int ct)
 #define TW     XO31( 4)
 #define TRAP   (TW | TO(31))
 
+#define SETBC    XO31(384)  /* v3.10 */
+#define SETBCR   XO31(416)  /* v3.10 */
+#define SETNBC   XO31(448)  /* v3.10 */
+#define SETNBCR  XO31(480)  /* v3.10 */
+
 #define NOP    ORI  /* ori 0,0,0 */
 
 #define LVX        XO31(103)
@@ -1624,6 +1629,23 @@ static void tcg_out_setcond(TCGContext *s, TCGType type, TCGCond cond,
         arg2 = (uint32_t)arg2;
     }
 
+    /* With SETBC/SETBCR, we can always implement with 2 insns. */
+    if (have_isa_3_10) {
+        tcg_insn_unit bi, opc;
+
+        tcg_out_cmp(s, cond, arg1, arg2, const_arg2, 7, type);
+
+        /* Re-use tcg_to_bc for BI and BO_COND_{TRUE,FALSE}. */
+        bi = tcg_to_bc[cond] & (0x1f << 16);
+        if (tcg_to_bc[cond] & BO(8)) {
+            opc = neg ? SETNBC : SETBC;
+        } else {
+            opc = neg ? SETNBCR : SETBCR;
+        }
+        tcg_out32(s, opc | RT(arg0) | bi);
+        return;
+    }
+
     /* Handle common and trivial cases before handling anything else.  */
     if (arg2 == 0) {
         switch (cond) {