softmmu templates: optionally pass CPUState to memory access functions

Optionally, make memory access helpers take a parameter for CPUState
instead of relying on global env.

On most targets, perform simple moves to reorder registers. On i386,
switch from regparm(3) calling convention to standard stack-based
version.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/exec-all.h b/exec-all.h
index 8fca67b..93a5b22 100644
--- a/exec-all.h
+++ b/exec-all.h
@@ -312,7 +312,9 @@
 
 #define ACCESS_TYPE (NB_MMU_MODES + 1)
 #define MEMSUFFIX _code
+#ifndef CONFIG_TCG_PASS_AREG0
 #define env cpu_single_env
+#endif
 
 #define DATA_SIZE 1
 #include "softmmu_header.h"