Fix oatdump crash on arm64/arm code.

Also adds 16 bit literal information.

Rationale:
When "run-away" instructions are disassembled, the literal
addresses may go out of range, causing oatdump to crash.
This CL guards memory access against the full memory range
allocated to assembly instructions and data (it is possible
but not really necessary to refine this a bit). Out of range
arguments are now displayed as (?) to denote the issue, which
is a lot nicer than crashing.

BUG=28670871

Change-Id: I51e9b6a6a99162546fe31059f14278e8980451c2

1 files changed, 9 insertions, 2 deletions

diff --git a/disassembler/disassembler_arm64.h b/disassembler/disassembler_arm64.h
index 44fa53f9f6..a4e5ee8a43 100644
--- a/disassembler/disassembler_arm64.h
+++ b/disassembler/disassembler_arm64.h
@@ -30,8 +30,11 @@ namespace arm64 {
 
 class CustomDisassembler FINAL : public vixl::Disassembler {
  public:
-  explicit CustomDisassembler(DisassemblerOptions* options) :
-      vixl::Disassembler(), read_literals_(options->can_read_literals_) {
+  explicit CustomDisassembler(DisassemblerOptions* options)
+      : vixl::Disassembler(),
+        read_literals_(options->can_read_literals_),
+        base_address_(options->base_address_),
+        end_address_(options->end_address_) {
     if (!options->absolute_addresses_) {
       MapCodeAddress(0, reinterpret_cast<const vixl::Instruction*>(options->base_address_));
     }
@@ -55,6 +58,10 @@ class CustomDisassembler FINAL : public vixl::Disassembler {
   //           true | 0x72681558: 1c000acb  ldr s11, pc+344 (addr 0x726816b0)
   //          false | 0x72681558: 1c000acb  ldr s11, pc+344 (addr 0x726816b0) (3.40282e+38)
   const bool read_literals_;
+
+  // Valid address range: [base_address_, end_address_)
+  const void* const base_address_;
+  const void* const end_address_;
 };
 
 class DisassemblerArm64 FINAL : public Disassembler {