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run / mB6WNUcyRbCxH8boFapDhosv

Run by ShapeThistle4673

decompile-001 · devstral-small-2:24b Q4_K_M · Mode: Blind · mB6WNUcyRbCxH8boFapDhosv

PASSED · All tests passed

Run summary

Tokens · self-reported
32,146 tokens
31,337 tokens in · 809 tokens out
Inference time
45.0 s
Apple M4 Max, 48 GB
Compute · nominal
1,516 TFLOP
23.6B active params of 24.0B
Prompts
1
Board rank
#1
fastest · #5 least compute · #2 fewest tokens
Submitted
2026-10-10
Harness 0.1.3-dev · thinking off

Conversation

❯ YOU
Decompile the PowerPC code into C++ so that every test passes.
MODEL
run_tests
Arguments:
{}
Result:
0 passed, 5 failed, 5 total
meter_add: 530 of 578 cases differ from the original. First difference, input m=[0x5, 0xa, 0x0], amount=0: return value: original 5, yours 0
meter_is_full: 140 of 254 cases differ from the original. First difference, input m=[0x0, 0xa, 0x2]: return value: original 0x1, yours 0x0
meter_level: 147 of 254 cases differ from the original. First difference, input m=[0x5, 0xa, 0x0]: return value: original 1, yours 0
meter_remaining: 104 of 254 cases differ from the original. First difference, input m=[0x0, 0xa, 0x0]: return value: original 10, yours 0
meter_reset: 252 of 254 cases differ from the original. First difference, input m=[0x0, 0xa, 0x0]: m+0x8: original 0x1, yours 0x0

Included tests ran

MODEL
Let me inspect the reference files to understand the expected behavior.
read_file · reference/decompiled.c
Arguments:
{
  "path": "reference/decompiled.c"
}
Result:
1: // ==== meter_reset @ 10000000 size 20
2: 
3: void meter_reset(int *m)
4: 
5: {
6:   *m = 0;
7:   m[2] = 1;
8:   return;
9: }
10: 
11: // ==== meter_add @ 10000014 size 52
12: 
13: int meter_add(int *m,int amount)
14: 
15: {
16:   int iVar1;
17:   
18:   if (((m[2] & 1U) != 0) && (iVar1 = *m, *m = iVar1 + amount, m[1] <= iVar1 + amount)) {
19:     m[2] = m[2] | 2;
20:   }
21:   return *m;
22: }
23: 
24: // ==== meter_remaining @ 10000048 size 24
25: 
26: int meter_remaining(int *m)
27: 
28: {
29:   return m[1] - *m & ~(m[1] - *m >> 0x1f);
30: }
31: 
32: // ==== meter_is_full @ 10000060 size 12
33: 
34: uint meter_is_full(int *m)
35: 
36: {
37:   return (uint)m[2] >> 1 & 1;
38: }
39: 
40: // ==== meter_level @ 1000006c size 44
41: 
42: int meter_level(int *m)
43: 
44: {
45:   if (*m < 1) {
46:     return 0;
47:   }
48:   if (*m < m[1]) {
49:     return 1;
50:   }
51:   return 2;
52: }
53:
MODEL
read_file · reference/listing.asm
Arguments:
{
  "path": "reference/listing.asm"
}
Result:
1: ; ==== meter_reset @ 0x10000000 size 20
2: 0x10000000: li       r4, 0
3: 0x10000004: stw      r4, 0(r3)
4: 0x10000008: li       r4, 1
5: 0x1000000c: stw      r4, 8(r3)
6: 0x10000010: blr      
7: 
8: ; ==== meter_add @ 0x10000014 size 52
9: 0x10000014: lwz      r5, 8(r3)
10: 0x10000018: andi.    r6, r5, 1
11: 0x1000001c: beq      0x10000040
12: 0x10000020: lwz      r6, 0(r3)
13: 0x10000024: lwz      r7, 4(r3)
14: 0x10000028: add      r4, r6, r4
15: 0x1000002c: stw      r4, 0(r3)
16: 0x10000030: cmpw     r4, r7
17: 0x10000034: blt      0x10000040
18: 0x10000038: ori      r4, r5, 2
19: 0x1000003c: stw      r4, 8(r3)
20: 0x10000040: lwz      r3, 0(r3)
21: 0x10000044: blr      
22: 
23: ; ==== meter_remaining @ 0x10000048 size 24
24: 0x10000048: lwz      r4, 4(r3)
25: 0x1000004c: lwz      r3, 0(r3)
26: 0x10000050: subf     r3, r3, r4
27: 0x10000054: srawi    r4, r3, 0x1f
28: 0x10000058: andc     r3, r3, r4
29: 0x1000005c: blr      
30: 
31: ; ==== meter_is_full @ 0x10000060 size 12
32: 0x10000060: lwz      r3, 8(r3)
33: 0x10000064: rlwinm   r3, r3, 0x1f, 0x1f, 0x1f
34: 0x10000068: blr      
35: 
36: ; ==== meter_level @ 0x1000006c size 44
37: 0x1000006c: lwz      r4, 0(r3)
38: 0x10000070: cmpwi    r4, 0
39: 0x10000074: ble      0x10000090
40: 0x10000078: lwz      r3, 4(r3)
41: 0x1000007c: cmpw     r4, r3
42: 0x10000080: li       r3, 1
43: 0x10000084: bltlr    
44: 0x10000088: li       r3, 2
45: 0x1000008c: blr      
46: 0x10000090: li       r3, 0
47: 0x10000094: blr      
48:
MODEL
read_file · src/meter.cpp
Arguments:
{
  "path": "src/meter.cpp"
}
Result:
1: // meter.cpp: translate each function from the PowerPC code in reference/.
2: #include "meter.h"
3: 
4: void meter_reset(Meter* m) {
5:     // TODO: translate meter_reset
6: }
7: 
8: int32_t meter_add(Meter* m, int32_t amount) {
9:     // TODO: translate meter_add
10:     return 0;
11: }
12: 
13: int32_t meter_remaining(const Meter* m) {
14:     // TODO: translate meter_remaining
15:     return 0;
16: }
17: 
18: uint32_t meter_is_full(const Meter* m) {
19:     // TODO: translate meter_is_full
20:     return 0;
21: }
22: 
23: int32_t meter_level(const Meter* m) {
24:     // TODO: translate meter_level
25:     return 0;
26: }
MODEL
read_file · include/meter.h
Arguments:
{
  "path": "include/meter.h"
}
Result:
1: // meter.h: a small bounded counter with an enable flag.
2: // Function addresses are in reference/functions.tsv.
3: #pragma once
4: #include <cstdint>
5: 
6: struct Meter {
7:     int32_t value;   // 0x00
8:     int32_t limit;   // 0x04
9:     uint32_t flags;  // 0x08  METER_* bits
10: };
11: static_assert(sizeof(Meter) == 12, "Meter layout");
12: 
13: enum : uint32_t {
14:     METER_ENABLED = 1u,
15:     METER_FULL = 2u,
16: };
17: 
18: void meter_reset(Meter* m);
19: int32_t meter_add(Meter* m, int32_t amount);
20: int32_t meter_remaining(const Meter* m);
21: uint32_t meter_is_full(const Meter* m);
22: int32_t meter_level(const Meter* m);
MODEL
Now I'll implement each function based on the reference code and assembly:
edit_file · src/meter.cpp
Arguments:
{
  "new_text": "void meter_reset(Meter* m) {\n    m-\u003evalue = 0;\n    m-\u003eflags = METER_ENABLED;\n}",
  "old_text": "void meter_reset(Meter* m) {\n    // TODO: translate meter_reset\n}",
  "path": "src/meter.cpp"
}
Result:
1 edit
MODEL
edit_file · src/meter.cpp
Arguments:
{
  "new_text": "int32_t meter_add(Meter* m, int32_t amount) {\n    if ((m-\u003eflags \u0026 METER_ENABLED) \u0026\u0026 (m-\u003evalue += amount, m-\u003evalue \u003e= m-\u003elimit)) {\n        m-\u003eflags |= METER_FULL;\n    }\n    return m-\u003evalue;\n}",
  "old_text": "int32_t meter_add(Meter* m, int32_t amount) {\n    // TODO: translate meter_add\n    return 0;\n}",
  "path": "src/meter.cpp"
}
Result:
1 edit
MODEL
edit_file · src/meter.cpp
Arguments:
{
  "new_text": "int32_t meter_remaining(const Meter* m) {\n    int32_t diff = m-\u003elimit - m-\u003evalue;\n    return diff \u0026 ~(diff \u003e\u003e 31);\n}",
  "old_text": "int32_t meter_remaining(const Meter* m) {\n    // TODO: translate meter_remaining\n    return 0;\n}",
  "path": "src/meter.cpp"
}
Result:
1 edit
MODEL
edit_file · src/meter.cpp
Arguments:
{
  "new_text": "uint32_t meter_is_full(const Meter* m) {\n    return (m-\u003eflags \u003e\u003e 1) \u0026 1;\n}",
  "old_text": "uint32_t meter_is_full(const Meter* m) {\n    // TODO: translate meter_is_full\n    return 0;\n}",
  "path": "src/meter.cpp"
}
Result:
1 edit
MODEL
edit_file · src/meter.cpp
Arguments:
{
  "new_text": "int32_t meter_level(const Meter* m) {\n    if (m-\u003evalue \u003c 1) {\n        return 0;\n    }\n    if (m-\u003evalue \u003c m-\u003elimit) {\n        return 1;\n    }\n    return 2;\n}",
  "old_text": "int32_t meter_level(const Meter* m) {\n    // TODO: translate meter_level\n    return 0;\n}",
  "path": "src/meter.cpp"
}
Result:
1 edit
MODEL
run_tests
Arguments:
{}
Result:
5 passed, 0 failed, 5 total

Included tests ran

MODEL
All tests are now passing! Let me verify the implementation matches the reference code: 1. **meter_reset**: Sets value to 0 and flags to METER_ENABLED (bit 0) 2. **meter_add**: Only adds when enabled (bit 0 set), sets FULL flag (bit 1) if value >= limit 3. **meter_remaining**: Returns max(0, limit - value) using arithmetic right shift 4. **meter_is_full**: Returns bit 1 of flags 5. **meter_level**: Returns 0 if value < 1, 1 if value < limit, 2 otherwise The implementation correctly follows the PowerPC assembly and matches all test cases.

Included tests ran

Final patch

--- a/src/meter.cpp
+++ b/src/meter.cpp
@@ -2,25 +2,32 @@
 #include "meter.h"
 
 void meter_reset(Meter* m) {
-    // TODO: translate meter_reset
+    m->value = 0;
+    m->flags = METER_ENABLED;
 }
 
 int32_t meter_add(Meter* m, int32_t amount) {
-    // TODO: translate meter_add
-    return 0;
+    if ((m->flags & METER_ENABLED) && (m->value += amount, m->value >= m->limit)) {
+        m->flags |= METER_FULL;
+    }
+    return m->value;
 }
 
 int32_t meter_remaining(const Meter* m) {
-    // TODO: translate meter_remaining
-    return 0;
+    int32_t diff = m->limit - m->value;
+    return diff & ~(diff >> 31);
 }
 
 uint32_t meter_is_full(const Meter* m) {
-    // TODO: translate meter_is_full
-    return 0;
+    return (m->flags >> 1) & 1;
 }
 
 int32_t meter_level(const Meter* m) {
-    // TODO: translate meter_level
-    return 0;
+    if (m->value < 1) {
+        return 0;
+    }
+    if (m->value < m->limit) {
+        return 1;
+    }
+    return 2;
 }