SUNNYVALE, Calif. --Advanced Micro Devices Inc. here today fired the opening salvo in the looming 64-bit microprocessor battle with Intel Corp. AMD released the full programmer development specs for its "Sledgehammer" 64-bit MPU, which is slated to go up against Intel's 64-bit Itanium chip in 2001 when both processors hit the market.
AMD drew the battle lines early by detailing how Sledgehammer will run legacy 32-bit x86 programs concurrently with new 64-bit software that will be developed. The processor senses whether the 32-bit or 64-bit mode is needed, according to the Sunnyvale company.
AMD and Intel immediately started flailing each other over how well their new 64-bit processors will run 32-bit legacy programs while migrating users to a new wider bit-word architecture. In releasing the Sledgehammer specs, AMD claimed the new processor extends the x86 architecture to a 64-bits word width, and it called the architecture an x86-64 instruction set to emphasize the fact. Steve Polzin, AMD's system architect, said application software developers can write 64-bit code to upgrade existing programs without emulation or recompiling.
Intel officials in nearby Santa Clara retorted that the upcoming 64-bit Itanium and successor McKinley processors will run 32-bit and 64-bit programs seamlessly on the same chip hardware. A bit switch sends 32-bit instructions to registers, which are designed in the chip to operate in a compatibility mode. Jason Waxman, Itanium design engineer, said there is no loss of performance in the native 32-bit mode, which operates interchangeably with the 64-bit mode.
The 32-bit compatibility will be a key issue for both the AMD and Intel 64-bit processors in many applications, such as network servers. These systems are expected initially to have a large amount of 32-bit legacy software applications, as well as libraries, plug-ins, and Java applets. However, in the design applications as well as high-performance engineering and scientific computing markets--which both AMD and Intel hope to crack with their new 64-bit processors--there is very little 32-bit legacy software.
The Intel Developers Forum, to be held in San Jose in two weeks, will ratchet up Intel's own campaign to lure programmers to write 64-bit software for the Itanium processor and for the successor Intel McKinley MPU, which is set to debut in late 2001.
Availability of new 64-bit applications software will be critical to AMD and Intel in their ability to sign up system customers for their new processors. For the first time, the two archrivals are split on the x86 architecture, with AMD and Intel going their separate ways in 64-bit chip design.
AMD got one extra boost today when Sun Microsystems Inc. touted the new Sledgehammer MPU for running Sun's Solaris-based software. Sun and Intel have broken off discussions to adapt Solaris for the Itanium and IA-64 architecture.
The Sledgehammer specifications released today include a compatibility mode to run 16- and 32-bit x86 programs without recompilation and a 64-bit mode. The chip adds eight 128-bit SSE registers for a total of 16 and eight general purpose registers for a total of 16.
AMD officials said the first Sledgehammer chip will be unveiled in 2001. It will be the first in a family of 64-bit processors.