tcg/tci: Move stack bounds check to compile-time

The existing check was incomplete:
(1) Only applied to two of the 7 stores, and not to the loads at all.
(2) Only checked the upper, but not the lower bound of the stack.

Doing this at compile time means that we don't need to do it
at runtime as well.

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

diff --git a/tcg/tci.c b/tcg/tci.c
index fe935e71a3b8e0807f3149b2e5213fff53cbffe8..ee2cd7dfa2b35cd5ae902dac155c3df3992b867c 100644 (file)
--- a/tcg/tci.c
+++ b/tcg/tci.c
@@ -628,7 +628,6 @@ uintptr_t QEMU_DISABLE_CFI tcg_qemu_tb_exec(CPUArchState *env,
             t0 = tci_read_r32(regs, &tb_ptr);
             t1 = tci_read_r(regs, &tb_ptr);
             t2 = tci_read_s32(&tb_ptr);
-            tci_assert(t1 != sp_value || (int32_t)t2 < 0);
             *(uint32_t *)(t1 + t2) = t0;
             break;
 
@@ -884,7 +883,6 @@ uintptr_t QEMU_DISABLE_CFI tcg_qemu_tb_exec(CPUArchState *env,
             t0 = tci_read_r64(regs, &tb_ptr);
             t1 = tci_read_r(regs, &tb_ptr);
             t2 = tci_read_s32(&tb_ptr);
-            tci_assert(t1 != sp_value || (int32_t)t2 < 0);
             *(uint64_t *)(t1 + t2) = t0;
             break;
 

diff --git a/tcg/tci/tcg-target.c.inc b/tcg/tci/tcg-target.c.inc
index f0f6b13112df72698f8265cf836e71de3c87af5e..82efb9af60af407a6fc69ccb30f739c18d46c5bd 100644 (file)
--- a/tcg/tci/tcg-target.c.inc
+++ b/tcg/tci/tcg-target.c.inc
@@ -375,10 +375,20 @@ static void tci_out_label(TCGContext *s, TCGLabel *label)
     }
 }
 
+static void stack_bounds_check(TCGReg base, target_long offset)
+{
+    if (base == TCG_REG_CALL_STACK) {
+        tcg_debug_assert(offset < 0);
+        tcg_debug_assert(offset >= -(CPU_TEMP_BUF_NLONGS * sizeof(long)));
+    }
+}
+
 static void tcg_out_ld(TCGContext *s, TCGType type, TCGReg ret, TCGReg arg1,
                        intptr_t arg2)
 {
     uint8_t *old_code_ptr = s->code_ptr;
+
+    stack_bounds_check(arg1, arg2);
     if (type == TCG_TYPE_I32) {
         tcg_out_op_t(s, INDEX_op_ld_i32);
         tcg_out_r(s, ret);
@@ -514,6 +524,7 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, const TCGArg *args,
     case INDEX_op_st16_i64:
     case INDEX_op_st32_i64:
     case INDEX_op_st_i64:
+        stack_bounds_check(args[1], args[2]);
         tcg_out_r(s, args[0]);
         tcg_out_r(s, args[1]);
         tcg_debug_assert(args[2] == (int32_t)args[2]);
@@ -716,6 +727,8 @@ static void tcg_out_st(TCGContext *s, TCGType type, TCGReg arg, TCGReg arg1,
                        intptr_t arg2)
 {
     uint8_t *old_code_ptr = s->code_ptr;
+
+    stack_bounds_check(arg1, arg2);
     if (type == TCG_TYPE_I32) {
         tcg_out_op_t(s, INDEX_op_st_i32);
         tcg_out_r(s, arg);