From c30b8dbe99b57dd21db29b79cc47d33b6007068c Mon Sep 17 00:00:00 2001
From: VelocityRa <makren67@gmail.com>
Date: Sat, 22 Sep 2018 21:00:50 +0300
Subject: [PATCH] decoders: Cast to correctly-sized type before shifting

Fixes decoding for 64-bit instructions

Does not help/apply to any currently supported ARM versions (since
all are 32-bit length or below), it's for future-proofing should
such an arch be supported.
---
 src/frontend/decoder/decoder_detail.h | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/frontend/decoder/decoder_detail.h b/src/frontend/decoder/decoder_detail.h
index 7a59820a..4a319ca8 100644
--- a/src/frontend/decoder/decoder_detail.h
+++ b/src/frontend/decoder/decoder_detail.h
@@ -36,16 +36,17 @@ private:
      * A '1' in a bitstring indicates that a one must be present at that bit position.
      */
     static auto GetMaskAndExpect(const char* const bitstring) {
+        const auto one = static_cast<opcode_type>(1);
         opcode_type mask = 0, expect = 0;
         for (size_t i = 0; i < opcode_bitsize; i++) {
             const size_t bit_position = opcode_bitsize - i - 1;
             switch (bitstring[i]) {
             case '0':
-                mask |= 1 << bit_position;
+                mask |= one << bit_position;
                 break;
             case '1':
-                expect |= 1 << bit_position;
-                mask |= 1 << bit_position;
+                expect |= one << bit_position;
+                mask |= one << bit_position;
                 break;
             default:
                 // Ignore
@@ -62,6 +63,7 @@ private:
      */
     template<size_t N>
     static auto GetArgInfo(const char* const bitstring) {
+        const auto one = static_cast<opcode_type>(1);
         std::array<opcode_type, N> masks = {};
         std::array<size_t, N> shifts = {};
         size_t arg_index = 0;
@@ -84,7 +86,7 @@ private:
                 }
 
                 ASSERT(arg_index < N);
-                masks[arg_index] |= 1 << bit_position;
+                masks[arg_index] |= one << bit_position;
                 shifts[arg_index] = bit_position;
             }
         }