1. Consider a 5-stage pipeline (IF, ID, EX, MEM, WB) processor implementation that does NOT use bypassing/forwarding and does NOT use delayed branches. Assume that register reads can occur in the same cycle that the register write-backs are done. For the below code, how many stalls will be observed? Assume that the loop runs a total of 1024 times.```Label: ldw r8, 0(r10) ; load into r8 from MEM[0+r10] add r9, r8, r7 ; r9 = r8 + r7 stw r9, 0(r12) ; store r9 into MEM[0+r12] addi r10, r10, 4 ; r10 = r10 + 4 addi r12, r12, 4 ; r12 = r12 + 4 bne r10, r11, Label; branch to Label if r10 != r11```**Explanation of the Code and Pipeline Considerations:**- **Pipeline Stages**: - IF: Instruction Fetch - ID: Instruction Decode - EX: Execute - MEM: Memory Access - WB: Write Back- **Operations**: - `ldw r8, 0(r10)`: Loads value into `r8` from memory address computed as `0 + value in r10`. - `add r9, r8, r7`: Adds values in `r8` and `r7` and stores the result in `r9`. - `stw r9, 0(r12)`: Stores the value from `r9` to memory address computed as `0 + value in r12`. - `addi r10, r10, 4`: Increments the value in `r10` by 4. - `addi r12, r12, 4`: Increments the value in `r12` by 4. - `bne r10, r11, Label`: Branches back to `Label` if `r10` does not equal `r11`.- **Considerations**: - The pipeline has a potential for stalls due to data hazards, as there is no bypassing/forwarding. - Data dependencies may occur, The given assembly code is to be analyzed for stalls in a 5-stage pipeline processor that includes the stages: Instruction Fetch (IF), Instruction Decode (ID), Execute (EX), Memory Access (MEM), and Write Back (WB). The processor utilizes bypassing/forwarding and includes a 1-cycle branch delay slot.### Pipeline Stages and Code Analysis:**Code:**1. `ldw r8, 0(r10)` - Load word into `r8` from memory address `0 + r10`.2. `add r9, r8, r7` - Add `r8` and `r7`, store the result in `r9`.3. `addi r10, r10, 4` - Add immediate value `4` to `r10`, store result in `r10`.4. `addi r12, r12, 4` - Add immediate value `4` to `r12`, store result in `r12`.5. `bne r10, r11, Label` - Branch to `Label` if `r10` is not equal to `r11`.6. `stw r9, -4(r12)` - Store word from `r9` into memory at address `-4 + r12`.### Key Considerations:- **Bypassing/Forwarding:** This is used to minimize stalls by directly forwarding data to dependent instructions without waiting for them to be written back to the register file.- **1-Cycle Branch Delay Slot:** The instruction immediately following a branch will execute regardless of the branch outcome.### Stalls:1. **Data Hazard between instructions 1 (`ldw`) and 2 (`add`):** - The `add` instruction depends on the result of the `ldw`, which might cause a stall if forwarding fails to resolve the dependency.2. **Branch Hazard at instruction 5 (`bne`):** - Even with a 1-cycle delay slot, control hazards (branch instructions) can cause stalls due to instruction fetches that might get invalidated if the branch is taken.### Total Stalls:Without explicit mention of forwarding mechanisms resolving these dependencies, generally:- **1 Stall** can be assumed for the data hazard from `ldw` to `add`. - **1 Stall** for the branch instruction `bne`, given the delay slot utilization.

Five stages, one step per stage1. IF: Instruction fetch from memory2. ID: Instruction decode &…

a 5-stage pipeline (IF, ID, EX, MEM, WB) processor implementa nat does use bypassing/forwarding and does NOT use delayed branches. Assume that register reads can occur in the same cycle that the register write-backs are done. For the below code, how many stalls will be observed? Assume that the loop runs a total of 1024 times. Label: Idw r8, 0(r10) ; load into r8 from MEM[0+r10] add r9, r8, r7; r9 = r8 + r7 stw r9, 0(r12); store r9 into MEM[0+r12] addi r10, r10, 4; r10 = r10 + 4 addi r12, r12, 4; r12 = r12 + 4 bne r10, r11, Label; branch to Label if r10 != r11

a 5-stage pipeline (IF, ID, EX, MEM, WB) processor implementa nat does use bypassing/forwarding and does NOT use delayed branches. Assume that register reads can occur in the same cycle that the register write-backs are done. For the below code, how many stalls will be observed? Assume that the loop runs a total of 1024 times. Label: Idw r8, 0(r10) ; load into r8 from MEM[0+r10] add r9, r8, r7; r9 = r8 + r7 stw r9, 0(r12); store r9 into MEM[0+r12] addi r10, r10, 4; r10 = r10 + 4 addi r12, r12, 4; r12 = r12 + 4 bne r10, r11, Label; branch to Label if r10 != r11

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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