Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
167 words
In a computing machine, apparatus for predicting the outcome of branch instructions, comprising: a processor; memory for storing information for said processor, said information including instructions and operands; first means for performing history based branch prediction, including means for recording prior branch actions of branch instructions processed by said processor; second means for detecting occurrences of modifications to operands upon which at least some of said recorded prior branch instruction actions depended and correcting at least some of said recorded prior branch instruction actions which would have been recorded differently if said modifications to operands had occurred before said recorded prior branch instruction actions were recorded; third means for detecting occurrences of said recorded prior branch instruction actions which have been corrected by said second means and which still fail to correctly predict future outcome of said branch instructions corresponding thereto; and fourth means for preventing further corrections to be made by said second means to said recorded prior branch instruction actions detected by said third means.
Claim 2
Dependent Claim
167 words
In a computing machine, apparatus for predicting the outcome of branch instructions, comprising: a processor; memory for storing information for said processor, said information including instructions and operands; first means for performing history based branch prediction, including means for recording prior branch actions of branch instructions processed by said processor; second means for detecting occurrences of modifications to operands upon which at least some of said recorded prior branch instruction actions depended and correcting at least some of said recorded prior branch instruction actions which would have been recorded differently if said modifications to operands had occurred before said recorded prior branch instruction actions were recorded; third means for detecting occurrences of said recorded prior branch instruction actions which have been corrected by said second means and which still fail to correctly predict future outcome of said branch instructions corresponding thereto; and fourth means for preventing further corrections to be made by said second means to said recorded prior branch instruction actions detected by said third means.
Claim 3
Dependent Claim
47 words
Apparatus for predicting the outcome of branch instructions, as defined in claim 1, and wherein said fourth means comprises: fifth means for preventing said second means from detecting occurrences of modifications to operands upon which said recorded prior branch instruction actions detected by said third means depended.
Claim 4
Dependent Claim
24 words
Apparatus for predicting the outcome of branch instructions, as defined in claim 2, and wherein said first means is a Branch History Table (BHT).
Claim 5
Dependent Claim
25 words
Apparatus for predicting the outcome of branch instructions, as defined in claim 3, and wherein said second means is a Data Dependent Branch Table (DDBT).
Claim 6
Dependent Claim
24 words
Apparatus for predicting the outcome of branch instructions, as defined in claim 2, and wherein said first means is a Decode History Table (DHT).
Claim 7
Dependent Claim
42 words
Apparatus for predicting the outcome of branch instructions, as defined in claim 2, and wherein said third means detects occurrences of a recorded prior branch instruction action where an address changes of an operand upon which said branch instruction corresponding thereto depends.
Claim 8
Dependent Claim
46 words
Apparatus for predicting the outcome of branch instructions, as defined in claim 1, and wherein said first means is a Branch History Table (BHT) and said third means includes first tag means for tagging entries in said BHT which have been corrected by said second means.
Claim 9
Dependent Claim
62 words
Apparatus for predicting the outcome of branch instructions, as defined in claim 7, and wherein said fourth means includes second tag means for further tagging said entries in said BHT which already have been tagged by said first tag means, said further tagged entries being entries which have resulted in a Branch Wrong Guess after having been corrected by said second means.
Claim 10
Dependent Claim
26 words
Apparatus for predicting the outcome of branch instructions, as defined in claim 8, and wherein said further tagged entries are not corrected by said second means.