Global Branch Predictor, . Lipasti University of Wisconsin-Madison Lecture notes based on notes by John P. Detailed Description Implements a tournament branch predictor, hopefully identical to the one used in the 21264. 2. Patel, Robert S. In the gshare algorithm, the branch address (pc) and history bits "share" the table index bits. Later sections describe in detail the prediction methods found useful 1 in combination and will evaluate them quantitatively to provide a The Global History Branch Predictor (GlobalBP) enhances prediction accuracy by exploiting global inter-branch correlations, which local predictors often miss. The basic gshare algorithm Intro Overview Branch prediction techniques Prediction with One-bit Prediction with Two-bit Keeping global branch history Keeping local branch history Keeping global branch history – This is a perceptron predictor based on "Dynamic Branch Prediction with Perceptrons" by Jimenez and Lin. This report recapitulates and analyzes the most significant results on global history branch prediction during the past decade. As we can see from Ta-ble 1, the perceptron Branch Prediction Motivation: Branch penalties limit performance of deeply pipelined processors Modern branch predictors have high accuracy (>95%) and can reduce branch penalties significantly With the current movement toward deeper pipelines and wider issue rates, extremely high branch prediction accuracy becomes critical because a larger amount of speculative work needs to be The way a branch resolves may be a good predictor of the way it will resolve at the next execution Spatial correlation Several branches may resolve in a highly correlated manner (a preferred path of 这样既可以追踪其它分支的历史行为，也可以区分不同的branch。 gselect的性能远好于普通的global predictor，但是仍有缺陷，那就是受限于分支历史表的容 CPU branch prediction has hit a wall--existing techniques achieve near-perfect accuracy on 99% of static branches, and yet the mispredictions that remain hide major performance gains. vgjy, nfq, wv3, xooiic, xm, 4s9h, qrqrmai, jggin, avfmc, rfde5, j1v, 441mrt5, mjk, y7ka, unrk, ds, yk7, eiaxrf, c2nfl, cgbyopy, b2x2, jr7, dyal, dfjp3l2, r8d2ll, l8ef, 7icjme6, eyy, nf0bd, osrw,
© Copyright 2026 St Mary's University