_jit_regs_load_value: if a value is in a global register and it is

ChangeLog

@@ -8,6 +8,10 @@
 	jit/jit-value.c, tools/gen-sel-parser.y: implement a simple global
 	register allocation policy, based on usage counts.
 
+	* jit/jit-reg-alloc.c (_jit_regs_load_value): if a value is in a
+	global register and it is not going to be destroyed by an instruction,
+	then use the global register as the operand.
+
 2004-06-01  Rhys Weatherley  <rweather@southern-storm.com.au>
 
 	* jit/jit-cache.c, jit/jit-elf-read.c, tools/gen-apply.c:

jit/jit-reg-alloc.c

@@ -1026,6 +1026,14 @@ int _jit_regs_load_value
 		}
 	}
 
+	/* If the value is in a global register, and we are not going
+	   to destroy the value, then use the global register itself.
+	   This will avoid a redundant register copy operation */
+	if(value->in_global_register && !destroy)
+	{
+		return value->global_reg;
+	}
+
 	/* Search for a free register to hold the value */
 	reg = free_register_for_value(gen, value, &other_reg);
 	load_value(gen, reg, other_reg, value, destroy);