5b69777647
GNU as has "la %r4,8(%r3)" as an alias for "addi %r4,%r3,8", meaning to load the address of the thing at 8(%r3). Our 'la', now 'li32', makes an addis/ori pair to load an immediate 32-bit value. For example, "li32 r4,23456789" loads a big number.
38 lines
735 B
ArmAsm
38 lines
735 B
ArmAsm
#
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! $Source$
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! $State$
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! $Revision$
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#include "powerpc.h"
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.sect .text
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! Index into a bounds-checked array.
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!
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! On entry:
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! r3 = ptr to descriptor
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! r4 = index
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! r5 = address of array
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! Yields:
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! r3 = address of element
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! r0 = size of element (used by .lar4, .sar4)
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! Preserves r10 for .lar4, .sar4
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.define .aar4
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.aar4:
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li32 r0, .trap_earray
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mtspr ctr, r0 ! load CTR with trap address
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lwz r0, 0(r3)
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subf. r4, r0, r4 ! adjust range
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bcctr IFTRUE, LT, 0 ! check lower bound
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lwz r0, 4(r3)
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cmpl cr0, 0, r4, r3
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bcctr IFFALSE, LT, 0 ! check upper bound
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lwz r0, 8(r3)
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mullw r4, r4, r0 ! scale index
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add r3, r4, r5 ! calculate element address
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bclr ALWAYS, 0, 0
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