diff --git a/target-arm/exec.h b/target-arm/exec.h
index 2d2b99aa38..deba89304c 100644
--- a/target-arm/exec.h
+++ b/target-arm/exec.h
@@ -19,10 +19,17 @@
  */
 #include "dyngen-exec.h"
 
+#if defined(__sparc__)
+struct CPUARMState *env;
+uint32_t T0;
+uint32_t T1;
+uint32_t T2;
+#else
 register struct CPUARMState *env asm(AREG0);
 register uint32_t T0 asm(AREG1);
 register uint32_t T1 asm(AREG2);
 register uint32_t T2 asm(AREG3);
+#endif
 
 /* TODO: Put these in FP regs on targets that have such things.  */
 /* It is ok for FT0s and FT0d to overlap.  Likewise FT1s and FT1d.  */
diff --git a/target-mips/exec.h b/target-mips/exec.h
index 15397b6920..1e9fa8e691 100644
--- a/target-mips/exec.h
+++ b/target-mips/exec.h
@@ -7,7 +7,11 @@
 #include "mips-defs.h"
 #include "dyngen-exec.h"
 
+#if defined(__sparc__)
+struct CPUMIPSState *env;
+#else
 register struct CPUMIPSState *env asm(AREG0);
+#endif
 
 #if defined (USE_64BITS_REGS)
 typedef int64_t host_int_t;
@@ -17,6 +21,11 @@ typedef int32_t host_int_t;
 typedef uint32_t host_uint_t;
 #endif
 
+#if defined(__sparc__)
+host_uint_t T0;
+host_uint_t T1;
+host_uint_t T2;
+#else
 #if TARGET_LONG_BITS > HOST_LONG_BITS
 #define T0 (env->t0)
 #define T1 (env->t1)
@@ -26,6 +35,7 @@ register host_uint_t T0 asm(AREG1);
 register host_uint_t T1 asm(AREG2);
 register host_uint_t T2 asm(AREG3);
 #endif
+#endif
 
 #if defined (USE_HOST_FLOAT_REGS)
 #error "implement me."
diff --git a/target-sparc/exec.h b/target-sparc/exec.h
index 1b67ef4bf6..6e0515f6e9 100644
--- a/target-sparc/exec.h
+++ b/target-sparc/exec.h
@@ -3,23 +3,41 @@
 #include "dyngen-exec.h"
 #include "config.h"
 
+#if defined(__sparc__)
+struct CPUSPARCState *env;
+#else
 register struct CPUSPARCState *env asm(AREG0);
+#endif
+
 #ifdef TARGET_SPARC64
 #define T0 (env->t0)
 #define T1 (env->t1)
 #define T2 (env->t2)
 #define REGWPTR env->regwptr
 #else
+#if defined(__sparc__)
+register uint32_t T0 asm(AREG3);
+register uint32_t T1 asm(AREG2);
+#else
 register uint32_t T0 asm(AREG1);
 register uint32_t T1 asm(AREG2);
+#endif
 
 #undef REG_REGWPTR // Broken
 #ifdef REG_REGWPTR
+#if defined(__sparc__)
+register uint32_t *REGWPTR asm(AREG4);
+#else
 register uint32_t *REGWPTR asm(AREG3);
+#endif
 #define reg_REGWPTR
 
 #ifdef AREG4
+#if defined(__sparc__)
+register uint32_t T2 asm(AREG0);
+#else
 register uint32_t T2 asm(AREG4);
+#endif
 #define reg_T2
 #else
 #define T2 (env->t2)
@@ -27,7 +45,11 @@ register uint32_t T2 asm(AREG4);
 
 #else
 #define REGWPTR env->regwptr
+#if defined(__sparc__)
+register uint32_t T2 asm(AREG0);
+#else
 register uint32_t T2 asm(AREG3);
+#endif
 #define reg_T2
 #endif
 #endif