disas: Fix printing of addresses in disassembly

In our disassembly code, the bfd_vma type is always 64 bits,
even if the target's virtual address width is only 32 bits. This
means that when we print out addresses we need to truncate them
to 32 bits, to avoid odd output which has incorrectly sign-extended
a value to 64 bits, for instance this ARM example:
    0x80479a60:  e59f4088     ldr  r4, [pc, #136]  ; 0xffffffff80479a4f

(It would also be possible to truncate before passing the address
to info->print_address_func(), but truncating in the final print
function is the same approach that binutils takes to this problem.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>

diff --git a/disas.c b/disas.c
index 93d8d30d1b8ae8ce4dea8d73b686017fee2a22de..7b2acc9943028a7bc8372a21e4bce26c72792ec1 100644 (file)
--- a/disas.c
+++ b/disas.c
@@ -64,6 +64,22 @@ generic_print_address (bfd_vma addr, struct disassemble_info *info)
     (*info->fprintf_func) (info->stream, "0x%" PRIx64, addr);
 }
 
+/* Print address in hex, truncated to the width of a target virtual address. */
+static void
+generic_print_target_address(bfd_vma addr, struct disassemble_info *info)
+{
+    uint64_t mask = ~0ULL >> (64 - TARGET_VIRT_ADDR_SPACE_BITS);
+    generic_print_address(addr & mask, info);
+}
+
+/* Print address in hex, truncated to the width of a host virtual address. */
+static void
+generic_print_host_address(bfd_vma addr, struct disassemble_info *info)
+{
+    uint64_t mask = ~0ULL >> (64 - (sizeof(void *) * 8));
+    generic_print_address(addr & mask, info);
+}
+
 /* Just return the given address.  */
 
 int
@@ -154,6 +170,7 @@ void target_disas(FILE *out, target_ulong code, target_ulong size, int flags)
     disasm_info.read_memory_func = target_read_memory;
     disasm_info.buffer_vma = code;
     disasm_info.buffer_length = size;
+    disasm_info.print_address_func = generic_print_target_address;
 
 #ifdef TARGET_WORDS_BIGENDIAN
     disasm_info.endian = BFD_ENDIAN_BIG;
@@ -274,6 +291,7 @@ void disas(FILE *out, void *code, unsigned long size)
     int (*print_insn)(bfd_vma pc, disassemble_info *info);
 
     INIT_DISASSEMBLE_INFO(disasm_info, out, fprintf);
+    disasm_info.print_address_func = generic_print_host_address;
 
     disasm_info.buffer = code;
     disasm_info.buffer_vma = (uintptr_t)code;
@@ -386,6 +404,7 @@ void monitor_disas(Monitor *mon, CPUArchState *env,
     monitor_disas_env = env;
     monitor_disas_is_physical = is_physical;
     disasm_info.read_memory_func = monitor_read_memory;
+    disasm_info.print_address_func = generic_print_target_address;
 
     disasm_info.buffer_vma = pc;