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| @@ -70,16 +70,76 @@ p3: · 69 unmodified lines | |||
| 70 | /* ---------------------------------------------- */ | 70 | /* ---------------------------------------------- */ |
| 71 | #elif defined __arm__ | 71 | #elif defined __arm__ |
| 72 | 72 | ||
| 73 | .text | 73 | .text |
| 74 | .align 2 | 74 | .align |
| 75 | .global alloca | 75 | .global alloca |
| 76 | .type alloca, %function | 76 | .type alloca, %function |
| 77 | alloca: | 77 | alloca: |
| 78 | rsb sp, r0, sp | 78 | rsb sp, r0, sp |
| 79 | bic sp, sp, #7 | 79 | bic sp, sp, #7 |
| 80 | mov r0, sp | 80 | mov r0, sp |
| 81 | mov pc, lr | 81 | mov pc, lr |
| 82 | .size alloca, .-alloca | 82 | .size alloca, .-alloca |
| 83 | 83 | ||
| 84 | /* ---------------------------------------------- */ | 84 | /* ---------------------------------------------- */ |
| 85 | #elif defined __aarch64__ || defined __arm64__ | ||
| 86 | |||
| 87 | .text | ||
| 88 | .align 2 | ||
| 89 | .global alloca | ||
| 90 | .type alloca, %function | ||
| 91 | alloca: | ||
| 92 | #ifdef __TINYC__ | ||
| 93 | .int 0x91003c00 | ||
| 94 | .int 0x927cec00 | ||
| 95 | #ifdef _WIN32 | ||
| 96 | .int 0xb4000160 | ||
| 97 | .int 0xd2820001 | ||
| 98 | .int 0xeb01001f | ||
| 99 | .int 0x540000c3 | ||
| 100 | .int 0xcb2163e2 | ||
| 101 | .int 0xf940005f | ||
| 102 | .int 0xcb2163ff | ||
| 103 | .int 0xcb010000 | ||
| 104 | .int 0x17fffffa | ||
| 105 | #endif | ||
| 106 | .int 0xb4000040 | ||
| 107 | .int 0xcb2063ff | ||
| 108 | .int 0x910003e0 | ||
| 109 | .int 0xd65f03c0 | ||
| 110 | #else | ||
| 111 | add x0, x0, #15 // Round up to 16-byte boundary | ||
| 112 | and x0, x0, #-16 // Ensure 16-byte alignment | ||
| 113 | cbz x0, p100 // If size is 0, skip to return | ||
| 114 | #ifdef _WIN32 | ||
| 115 | // Windows requires page-wise allocation with stack probing | ||
| 116 | mov x1, #4096 // Page size = 4096 bytes | ||
| 117 | |||
| 118 | p101: | ||
| 119 | cmp x0, x1 // Compare remaining size with page size | ||
| 120 | b.lo p102 // If less than page, jump to remainder | ||
| 121 | |||
| 122 | // Probe first, then allocate | ||
| 123 | sub x2, sp, x1 // Calculate guard page address (sp - 4096) | ||
| 124 | ldr xzr, [x2] // Touch guard page FIRST | ||
| 125 | sub sp, sp, x1 // THEN allocate the page | ||
| 126 | |||
| 127 | sub x0, x0, x1 // Decrement remaining size | ||
| 128 | b p101 // Continue loop | ||
| 129 | |||
| 130 | p102: | ||
| 131 | // Allocate remaining bytes (less than one page) | ||
| 132 | cbz x0, p100 // If no remaining bytes, skip | ||
| 133 | sub sp, sp, x0 // Allocate remaining space | ||
| 134 | #else | ||
| 135 | // Non-Windows: simple one-time allocation | ||
| 136 | sub sp, sp, x0 // Allocate space on stack | ||
| 137 | #endif | ||
| 138 | |||
| 139 | p100: | ||
| 140 | mov x0, sp // Return allocated address | ||
| 141 | ret // Return to caller | ||
| 142 | #endif | ||
| 143 | .size alloca, .-alloca | ||
| 144 | /* ---------------------------------------------- */ | ||
| 85 | #endif | 145 | #endif |