tci: Make tcg temporaries local to tcg_qemu_tb_exec

We're moving away from the temporaries stored in env.  Make sure we can
differentiate between temp stores and possibly bogus stores for extra
call arguments.  Move TCG_AREG0 and TCG_REG_CALL_STACK out of the way
of the parameter passing registers.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off by: Stefan Weil <sw@weilnetz.de>

1 files changed, 6 insertions, 0 deletions

diff --git a/tci.c b/tci.c
index 70f8308f93..c742c8df5c 100644
--- a/tci.c
+++ b/tci.c
@@ -112,6 +112,7 @@ static void tci_write_reg(TCGReg index, tcg_target_ulong value)
 {
     assert(index < ARRAY_SIZE(tci_reg));
     assert(index != TCG_AREG0);
+    assert(index != TCG_REG_CALL_STACK);
     tci_reg[index] = value;
 }
 
@@ -435,9 +436,12 @@ static bool tci_compare64(uint64_t u0, uint64_t u1, TCGCond condition)
 /* Interpret pseudo code in tb. */
 tcg_target_ulong tcg_qemu_tb_exec(CPUArchState *env, uint8_t *tb_ptr)
 {
+    long tcg_temps[CPU_TEMP_BUF_NLONGS];
+    uintptr_t sp_value = (uintptr_t)(tcg_temps + CPU_TEMP_BUF_NLONGS);
     tcg_target_ulong next_tb = 0;
 
     tci_reg[TCG_AREG0] = (tcg_target_ulong)env;
+    tci_reg[TCG_REG_CALL_STACK] = sp_value;
     assert(tb_ptr);
 
     for (;;) {
@@ -585,6 +589,7 @@ tcg_target_ulong tcg_qemu_tb_exec(CPUArchState *env, uint8_t *tb_ptr)
             t0 = tci_read_r32(&tb_ptr);
             t1 = tci_read_r(&tb_ptr);
             t2 = tci_read_s32(&tb_ptr);
+            assert(t1 != sp_value || (int32_t)t2 < 0);
             *(uint32_t *)(t1 + t2) = t0;
             break;
 
@@ -869,6 +874,7 @@ tcg_target_ulong tcg_qemu_tb_exec(CPUArchState *env, uint8_t *tb_ptr)
             t0 = tci_read_r64(&tb_ptr);
             t1 = tci_read_r(&tb_ptr);
             t2 = tci_read_s32(&tb_ptr);
+            assert(t1 != sp_value || (int32_t)t2 < 0);
             *(uint64_t *)(t1 + t2) = t0;
             break;