tcg/s390x: Use ALGFR in constructing softmmu host address

Rather than zero-extend the guest address into a register,
use an add instruction which zero-extends the second input.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

tcg/s390x/tcg-target.c.inc

@@ -149,6 +149,7 @@ typedef enum S390Opcode {
     RRE_ALGR    = 0xb90a,
     RRE_ALCR    = 0xb998,
     RRE_ALCGR   = 0xb988,
+    RRE_ALGFR   = 0xb91a,
     RRE_CGR     = 0xb920,
     RRE_CLGR    = 0xb921,
     RRE_DLGR    = 0xb987,
@@ -1853,10 +1854,11 @@ static TCGLabelQemuLdst *prepare_host_addr(TCGContext *s, HostAddress *h,
     tcg_out_insn(s, RXY, LG, h->index, TCG_REG_R2, TCG_REG_NONE,
                  offsetof(CPUTLBEntry, addend));
 
-    h->base = addr_reg;
     if (TARGET_LONG_BITS == 32) {
-        tcg_out_ext32u(s, TCG_REG_R3, addr_reg);
-        h->base = TCG_REG_R3;
+        tcg_out_insn(s, RRE, ALGFR, h->index, addr_reg);
+        h->base = TCG_REG_NONE;
+    } else {
+        h->base = addr_reg;
     }
     h->disp = 0;
 #else