PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set Vega bl the_admin Posts: 3,279 Threads: 842 Joined: Feb 2018 Reputation: 80 07-04-2021, 12:28 PM (This post was last modified: 07-04-2021, 12:28 PM by Vega.) It's called the Effective Address and that's how store and load instructions work. Examples~ stw r0, VALUE (r3) #Effective Address aka EA (where store occurs) is VALUE+r3 lbz r5, VALUE (r10) #EA = VALUE+r10 These calculations are signed because all store and load instructions are signed. Meaning VALUE can be negative. If it is, do the sum accordingly. Example~ lhzu r11, 0xFFFFFFFC (r9) #EA = -4 + r9, or easier to write it as r9 - 4 = EA. Final Example (using lwxz)~ r5 = 0xFFFFFFF0 (aka -16 or -0x10) r6 = 0x80001000 lwxz r4, r5, r6 EA = r5+r6 (0x80001000 minus 0x10) Thus EA = 0x80000FF0 So the lwzx instruction will load the word located at 0x80000FF0 into r4. « Next Oldest | Next Newest »

 Messages In This Thread PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 06-22-2021, 07:48 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by WhatisLoaf - 06-23-2021, 09:07 AM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 06-23-2021, 04:04 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by Seeky - 06-23-2021, 04:57 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 06-23-2021, 05:59 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by Vega - 06-23-2021, 10:00 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 06-24-2021, 12:22 AM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by Vega - 06-25-2021, 12:09 AM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 06-25-2021, 05:17 AM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by Vega - 06-25-2021, 09:34 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 06-25-2021, 10:19 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by Vega - 06-27-2021, 02:07 AM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 06-27-2021, 04:22 AM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by Vega - 06-27-2021, 12:34 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 06-27-2021, 10:23 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by Vega - 06-27-2021, 11:17 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 06-28-2021, 04:29 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by Vega - 06-28-2021, 06:21 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 06-28-2021, 09:45 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by Vega - 06-28-2021, 10:44 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 06-29-2021, 04:08 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 07-03-2021, 06:22 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by Vega - 07-03-2021, 11:15 PM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by JimmyKazakhstan - 07-04-2021, 02:33 AM RE: PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set - by Vega - 07-04-2021, 12:28 PM

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