2018-09-09 23:08:25 +00:00
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#
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.sect .text; .sect .rom; .sect .data; .sect .bss
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/* Bounds check. Traps if the value is out of range.
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* Stack: ( value descriptor -- value )
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*
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* This ".rck" only works with 4-byte integers. The name is ".rck" and
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* not ".rck4" because many back ends only do rck with the word size.
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*/
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.sect .text
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.define .rck
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.rck:
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lw r4, 0(sp) ! r4 = pointer to descriptor
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addiu sp, sp, 4 ! leave value on stack
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lw r5, 0(sp) ! r5 = value
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2018-09-13 22:38:31 +00:00
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lw at, 0(r4) ! at = lower bound
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2018-09-09 23:08:25 +00:00
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slt at, r5, at ! at = r5 < at
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bne at, zero, .trap_erange
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2018-09-13 22:38:31 +00:00
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nop
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2018-09-09 23:08:25 +00:00
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2018-09-13 22:38:31 +00:00
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lw at, 4(r4) ! at = upper bound
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2018-09-09 23:08:25 +00:00
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slt at, at, r5 ! at = at < r5
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bne at, zero, .trap_erange
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2018-09-13 22:38:31 +00:00
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nop
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2018-09-09 23:08:25 +00:00
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jr ra
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nop
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.define .trap_erange
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.trap_erange:
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li r4, 1
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j .trp
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nop
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