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Fix csel instruction use to match intended ternary operator

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d 2025-02-28 12:55:17 -08:00
parent 8e8c700b48
commit 89d8a1fe9b
1 changed files with 6 additions and 6 deletions
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12
section_1/regs/ldr.md
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@ -503,9 +503,9 @@ FindOldestPerson: // 13
b 10f // enter loop // 20 b 10f // enter loop // 20
// 21 // 21
1: ldr w5, [x3, p.age] // fetch loop ptr -> age // 22 1: ldr w5, [x3, p.age] // fetch loop ptr -> age // 22
cmp w2, w5 // compare to oldest_age // 23 cmp w5, w2 // compare to oldest_age // 23
csel w2, w2, w5, gt // update based on cmp // 24 csel w2, w5, w2, gt // update based on cmp // 24
csel x0, x0, x3, gt // update based on cmp // 25 csel x0, x3, x0, gt // update based on cmp // 25
add x3, x3, 24 // increment loop ptr // 26 add x3, x3, 24 // increment loop ptr // 26
10: cmp x3, x4 // has loop ptr reached end_ptr? // 27 10: cmp x3, x4 // has loop ptr reached end_ptr? // 27
blt 1b // no, not yet // 28 blt 1b // no, not yet // 28
@ -670,15 +670,15 @@ resulted in a less than zero, zero, or more than zero result.
`Lines 24` and `25` read: `Lines 24` and `25` read:
```asm ```asm
csel w2, w2, w5, gt // update based on cmp // 24 csel w2, w5, w2, gt // update based on cmp // 24
csel x0, x0, x3, gt // update based on cmp // 25 csel x0, x3, x0, gt // update based on cmp // 25
``` ```
These are identical to this: These are identical to this:
```c ```c
w2 = (w5 > w2) ? w5 : w2; w2 = (w5 > w2) ? w5 : w2;
x0 = (x5 > x2) ? x3 : x0; x0 = (w5 > w2) ? x3 : x0;
``` ```
**Remember that the condition or status bits have already been set based **Remember that the condition or status bits have already been set based