diff options
Diffstat (limited to 'erts/emulator/beam/jit/x86/beam_asm.hpp')
| -rw-r--r-- | erts/emulator/beam/jit/x86/beam_asm.hpp | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/erts/emulator/beam/jit/x86/beam_asm.hpp b/erts/emulator/beam/jit/x86/beam_asm.hpp index dee1edebb5..5e83c7e83c 100644 --- a/erts/emulator/beam/jit/x86/beam_asm.hpp +++ b/erts/emulator/beam/jit/x86/beam_asm.hpp @@ -795,7 +795,20 @@ protected: void mov_imm(x86::Gp to, T value) { static_assert(std::is_integral<T>::value || std::is_pointer<T>::value); if (value) { - a.mov(to, imm(value)); + /* Generate the shortest instruction to set the register to an + * immediate. + * + * 48 c7 c0 2a 00 00 00 mov rax, 42 + * b8 2a 00 00 00 mov eax, 42 + * + * 49 c7 c0 2a 00 00 00 mov r8, 42 + * 41 b8 2a 00 00 00 mov r8d, 42 + */ + if (Support::isUInt32((Uint)value)) { + a.mov(to.r32(), imm(value)); + } else { + a.mov(to, imm(value)); + } } else { /* * Generate the shortest instruction to set the register to zero. |