Re: OoO execution

quadibloc wrote:

On Mon, 19 May 2025 6:22:42 +0000, Anton Ertl wrote:
 

You are probably thinking of OoO Execution, where people usually write
as if the Tomasulo algorithm of the 360/91 as implemented the modern
concept of OoO execution.  But the 360/91 only did OoO for FP, did not
support branch prediction, had imprecise exceptions, and the Tomasulo
algorithm was used primarily as a workaround for the dearth of FP
registers in the S/360.

 Yes, I was thinking of OoO execution, as opposed to other forms of
pipelining - basic pipelining was used in the 7094 II and even the 6502.
 The Pentium II (and Pentium Pro) also only used OoO for floating-point,
while the 68050 only used OoO for integers!

Huh???
The Pentium (all versions) had two pipes (u & v), both in-order, and with severe limitations on which opcodes could run in v in parallel with the primary opcode in the u pipe.
The P6/PentiumPro OTOH does true OoO for all instruction types.
John, you are usually much better informed!
Terje
--
- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"