57 lines
650 B
Markdown
57 lines
650 B
Markdown
# Code Generation 2
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## Stack Machine
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Consider two instructions
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* `push i`
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* `add i`
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It is not efficient because all stack is considered as memory (which is slower than register).
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### Utilizing Register Files
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Keep the top of the stack in a register, so `add` requires only a single memory access.
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* `acc <- i`
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* `push acc`
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* `pop`
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* `add`
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### Code Generation From Stack Machine
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Assume that stack grows towards lower addresses.
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## MIPS
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32 regs
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`$sp`, `$a0`, `$t1`
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* `lw`
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* `add`
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* `sw`
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* `addi`
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* `li`
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* `mv`
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Converting Stack to MIPS ISA
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* `acc <- i`
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* `li $a0 i`
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### Optimizing
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## Branch
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`beq $1 $2 lbl`
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`b lbl`
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## Function
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