fix(compiler): asm 约束映射补全 8 位寄存器 clobber（AL/AH/BL/BH/CL/CH/DL/DH）

App/lib/core/Gen/Call/CallGenCBuiltin.vp

@@ -844,6 +844,17 @@ class CallGenCBuiltin(CallGenBase.CallGenBase):
         if string.strcmp(attr_name, "CLOBBER_CX") == 0:     return "cx"
         if string.strcmp(attr_name, "CLOBBER_SI") == 0:     return "si"
         if string.strcmp(attr_name, "CLOBBER_DI") == 0:     return "di"
+        # 8 位寄存器破坏描述符（对齐 t.py 标准常量集；缺 AL 曾致 AllocPage
+        # `rep stosb` 的 ~{al} 丢失——LLVM 不知 AL 被改，页地址 $0 可能被分配
+        # 进 RAX 被 mov al,0 破坏，A7 根因）
+        if string.strcmp(attr_name, "CLOBBER_AL") == 0:     return "al"
+        if string.strcmp(attr_name, "CLOBBER_AH") == 0:     return "ah"
+        if string.strcmp(attr_name, "CLOBBER_BL") == 0:     return "bl"
+        if string.strcmp(attr_name, "CLOBBER_BH") == 0:     return "bh"
+        if string.strcmp(attr_name, "CLOBBER_CL") == 0:     return "cl"
+        if string.strcmp(attr_name, "CLOBBER_CH") == 0:     return "ch"
+        if string.strcmp(attr_name, "CLOBBER_DL") == 0:     return "dl"
+        if string.strcmp(attr_name, "CLOBBER_DH") == 0:     return "dh"
 
         # Output 输出约束
         if string.strcmp(attr_name, "OUTPUT_REG") == 0: return "=r"