06+-+Tomasulo - CS 4290/6290 Tom asulo's Algorithm Branch...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
CS 4290/6290 Tomasulo’s Algorithm
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Branch prediction removes (most of) the control dependences Register renaming eliminates WAR and WAW false dependences So let’s start executing instructions out-of-order to exploit the available ILP CS 4290/6290 – Spring 2009 – Prof. Milos Prvulovic I1: ADD R1, R2, R3 I2: SUB R2, R1, R5 I3: AND R5 R11, R7 I4: OR R8, R5, R2 I5: XOR R2, R4, R11 I4: OR R8, S , R2 I3: AND S , R11, R7 I2: SUB R2, R1, R5 I5: XOR T , R4, R11 2
Background image of page 2
Tomasulo’s Algorithm Used in IBM 360/91 (in the 60s) Tracks when operands are available to satisfy data dependences Removes name dependences through register renaming Very similar to what is used today • Almost all modern high-performance processors use a derivative of Tomasulo’s… much of the terminology survives to today. CS 4290/6290 – Spring 2009 – Prof. Milos Prvulovic 3
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
CS 4290/6290 – Spring 2009 – Prof. Milos Prvulovic 4
Background image of page 4
Get next instruction from instruction queue. Find a free reservation station for it (if none are free, stall until one is) Read operands that are in the registers If the operand is not in the register, find which reservation station will produce it In effect, this step renames registers (reservation station IDs are “temporary” names) CS 4290/6290 – Spring 2009 – Prof. Milos Prvulovic 5
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
CS 4290/6290 – Spring 2009 – Prof. Milos Prvulovic F1 = F2 + F3 F4 = F1 – F2 F1 = F2 / F3
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/12/2010 for the course CS 6290 taught by Professor Staff during the Spring '08 term at Georgia Institute of Technology.

Page1 / 17

06+-+Tomasulo - CS 4290/6290 Tom asulo's Algorithm Branch...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online