Use the pcRel macro to compute the current pc.
#95
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The line of code in this commit was off-by-one, though in a way that didn't undermine the correctness of yk per se, since we were always off-by-one. However, it would have meant that we wrote to the word immediately past the end of an allocation, which is UB. The cause of this is the `vmfetch` macro, executed before the line of code changed by this commit which increments `pc`: thus by the time we execute the line of code in this commit, `pc` no longer points to the actual `pc` we wanted, but one after it. The `pcRel` macro does the necessary magic (i.e. subtracting 1) to resolve this.
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The line of code in this commit was off-by-one, though in a way that didn't undermine the correctness of yk per se, since we were always off-by-one. However, it would have meant that we wrote to the word immediately past the end of an allocation, which is UB.
The cause of this is the
vmfetchmacro, executed before the line of code changed by this commit which incrementspc: thus by the time we execute the line of code in this commit,pcno longer points to the actualpcwe wanted, but one after it. ThepcRelmacro does the necessary magic (i.e. subtracting 1) to resolve this.