tcg: Avoid undefined behaviour patching code at unaligned addresses

[qemu.git] / tcg / i386 / tcg-target.c

diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c
index fef17174184fceca3d0af07fdf81a1ff539477fd..9a585ab5ecccca3dd3f1b61d5b55eb526715bef2 100644 (file)
--- a/tcg/i386/tcg-target.c
+++ b/tcg/i386/tcg-target.c
@@ -115,7 +115,7 @@ static const int tcg_target_call_oarg_regs[] = {
    is available.  */
 #if TCG_TARGET_REG_BITS == 64
 # define have_cmov 1
-#elif defined(CONFIG_CPUID_H)
+#elif defined(CONFIG_CPUID_H) && defined(bit_CMOV)
 static bool have_cmov;
 #else
 # define have_cmov 0
@@ -151,14 +151,14 @@ static void patch_reloc(uint8_t *code_ptr, int type,
         if (value != (int32_t)value) {
             tcg_abort();
         }
-        *(uint32_t *)code_ptr = value;
+        tcg_patch32(code_ptr, value);
         break;
     case R_386_PC8:
         value -= (uintptr_t)code_ptr;
         if (value != (int8_t)value) {
             tcg_abort();
         }
-        *(uint8_t *)code_ptr = value;
+        tcg_patch8(code_ptr, value);
         break;
     default:
         tcg_abort();
@@ -257,7 +257,7 @@ static int target_parse_constraint(TCGArgConstraint *ct, const char **pct_str)
 }
 
 /* test if a constant matches the constraint */
-static inline int tcg_target_const_match(tcg_target_long val,
+static inline int tcg_target_const_match(tcg_target_long val, TCGType type,
                                          const TCGArgConstraint *arg_ct)
 {
     int ct = arg_ct->ct;
@@ -1244,7 +1244,7 @@ static inline void tcg_out_tlb_load(TCGContext *s, TCGReg addrlo, TCGReg addrhi,
  * Record the context of a call to the out of line helper code for the slow path
  * for a load or store, so that we can later generate the correct helper code
  */
-static void add_qemu_ldst_label(TCGContext *s, int is_ld, TCGMemOp opc,
+static void add_qemu_ldst_label(TCGContext *s, bool is_ld, TCGMemOp opc,
                                 TCGReg datalo, TCGReg datahi,
                                 TCGReg addrlo, TCGReg addrhi,
                                 int mem_index, uint8_t *raddr,
@@ -1276,9 +1276,9 @@ static void tcg_out_qemu_ld_slow_path(TCGContext *s, TCGLabelQemuLdst *l)
     uint8_t **label_ptr = &l->label_ptr[0];
 
     /* resolve label address */
-    *(uint32_t *)label_ptr[0] = (uint32_t)(s->code_ptr - label_ptr[0] - 4);
+    tcg_patch32(label_ptr[0], s->code_ptr - label_ptr[0] - 4);
     if (TARGET_LONG_BITS > TCG_TARGET_REG_BITS) {
-        *(uint32_t *)label_ptr[1] = (uint32_t)(s->code_ptr - label_ptr[1] - 4);
+        tcg_patch32(label_ptr[1], s->code_ptr - label_ptr[1] - 4);
     }
 
     if (TCG_TARGET_REG_BITS == 32) {
@@ -1360,9 +1360,9 @@ static void tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *l)
     TCGReg retaddr;
 
     /* resolve label address */
-    *(uint32_t *)label_ptr[0] = (uint32_t)(s->code_ptr - label_ptr[0] - 4);
+    tcg_patch32(label_ptr[0], s->code_ptr - label_ptr[0] - 4);
     if (TARGET_LONG_BITS > TCG_TARGET_REG_BITS) {
-        *(uint32_t *)label_ptr[1] = (uint32_t)(s->code_ptr - label_ptr[1] - 4);
+        tcg_patch32(label_ptr[1], s->code_ptr - label_ptr[1] - 4);
     }
 
     if (TCG_TARGET_REG_BITS == 32) {
@@ -1554,7 +1554,7 @@ static void tcg_out_qemu_ld(TCGContext *s, const TCGArg *args, bool is64)
     tcg_out_qemu_ld_direct(s, datalo, datahi, TCG_REG_L1, 0, 0, opc);
 
     /* Record the current context of a load into ldst label */
-    add_qemu_ldst_label(s, 1, opc, datalo, datahi, addrlo, addrhi,
+    add_qemu_ldst_label(s, true, opc, datalo, datahi, addrlo, addrhi,
                         mem_index, s->code_ptr, label_ptr);
 #else
     {
@@ -1685,7 +1685,7 @@ static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args, bool is64)
     tcg_out_qemu_st_direct(s, datalo, datahi, TCG_REG_L1, 0, 0, opc);
 
     /* Record the current context of a store into ldst label */
-    add_qemu_ldst_label(s, 0, opc, datalo, datahi, addrlo, addrhi,
+    add_qemu_ldst_label(s, false, opc, datalo, datahi, addrlo, addrhi,
                         mem_index, s->code_ptr, label_ptr);
 #else
     {
@@ -2295,6 +2295,7 @@ static void tcg_target_qemu_prologue(TCGContext *s)
 
 static void tcg_target_init(TCGContext *s)
 {
+#ifdef CONFIG_CPUID_H
     unsigned a, b, c, d;
     int max = __get_cpuid_max(0, 0);
 
@@ -2323,6 +2324,7 @@ static void tcg_target_init(TCGContext *s)
         have_bmi2 = (b & bit_BMI2) != 0;
 #endif
     }
+#endif
 
     if (TCG_TARGET_REG_BITS == 64) {
         tcg_regset_set32(tcg_target_available_regs[TCG_TYPE_I32], 0, 0xffff);