From 3cf03158599472b1f6713192d9fa2b120f9f209b Mon Sep 17 00:00:00 2001 From: Kartik Agaram Date: Sat, 7 Mar 2020 17:32:39 -0800 Subject: 6094 - new 'compute-offset' instruction If indexing into a type with power-of-2-sized elements we can access them in one instruction: x/reg1: (addr int) <- index A/reg2: (addr array int), idx/reg3: int This translates to a single instruction because x86 instructions support an addressing mode with left-shifts. For non-powers-of-2, however, we need a multiply. To keep things type-safe, it is performed like this: x/reg1: (offset T) <- compute-offset A: (addr array T), idx: int y/reg2: (addr T) <- index A, x An offset is just an int that is guaranteed to be a multiple of size-of(T). Offsets can only be used in index instructions, and the types will eventually be required to line up. In the process, I have to expand Input-size because mu.subx is growing big. --- apps/survey | Bin 50093 -> 50093 bytes 1 file changed, 0 insertions(+), 0 deletions(-) (limited to 'apps/survey') diff --git a/apps/survey b/apps/survey index 516ee21b..49905f1a 100755 Binary files a/apps/survey and b/apps/survey differ -- cgit 1.4.1-2-gfad0