| Howard Hinnant | 9ad441f | 2010-11-16 22:13:33 +0000 | [diff] [blame] | 1 | // This file is dual licensed under the MIT and the University of Illinois Open |
| 2 | // Source Licenses. See LICENSE.TXT for details. |
| Daniel Dunbar | b3a6901 | 2009-06-26 16:47:03 +0000 | [diff] [blame] | 3 | |
| Daniel Dunbar | 19336a2 | 2009-10-27 17:49:50 +0000 | [diff] [blame] | 4 | #include "../assembly.h" |
| 5 | |
| Daniel Dunbar | b3a6901 | 2009-06-26 16:47:03 +0000 | [diff] [blame] | 6 | // long double __floatundixf(du_int a); |
| 7 | |
| 8 | #ifdef __x86_64__ |
| 9 | |
| Edward O'Callaghan | eed1300 | 2009-11-04 23:52:51 +0000 | [diff] [blame] | 10 | #ifndef __ELF__ |
| Daniel Dunbar | b3a6901 | 2009-06-26 16:47:03 +0000 | [diff] [blame] | 11 | .const |
| Edward O'Callaghan | eed1300 | 2009-11-04 23:52:51 +0000 | [diff] [blame] | 12 | #endif |
| Daniel Dunbar | b3a6901 | 2009-06-26 16:47:03 +0000 | [diff] [blame] | 13 | .align 4 |
| 14 | twop64: .quad 0x43f0000000000000 |
| 15 | |
| 16 | #define REL_ADDR(_a) (_a)(%rip) |
| 17 | |
| 18 | .text |
| 19 | .align 4 |
| Daniel Dunbar | b4b1e8c | 2009-10-27 17:50:21 +0000 | [diff] [blame] | 20 | DEFINE_COMPILERRT_FUNCTION(__floatundixf) |
| Daniel Dunbar | b3a6901 | 2009-06-26 16:47:03 +0000 | [diff] [blame] | 21 | movq %rdi, -8(%rsp) |
| 22 | fildq -8(%rsp) |
| 23 | test %rdi, %rdi |
| 24 | js 1f |
| 25 | ret |
| 26 | 1: faddl REL_ADDR(twop64) |
| 27 | ret |
| 28 | |
| 29 | #endif // __x86_64__ |
| 30 | |
| 31 | |
| 32 | /* Branch-free implementation is ever so slightly slower, but more beautiful. |
| 33 | It is likely superior for inlining, so I kept it around for future reference. |
| 34 | |
| 35 | #ifdef __x86_64__ |
| 36 | |
| 37 | .const |
| 38 | .align 4 |
| 39 | twop52: .quad 0x4330000000000000 |
| 40 | twop84_plus_twop52_neg: |
| 41 | .quad 0xc530000000100000 |
| 42 | twop84: .quad 0x4530000000000000 |
| 43 | |
| 44 | #define REL_ADDR(_a) (_a)(%rip) |
| 45 | |
| 46 | .text |
| 47 | .align 4 |
| Daniel Dunbar | b4b1e8c | 2009-10-27 17:50:21 +0000 | [diff] [blame] | 48 | DEFINE_COMPILERRT_FUNCTION(__floatundixf) |
| Daniel Dunbar | b3a6901 | 2009-06-26 16:47:03 +0000 | [diff] [blame] | 49 | movl %edi, %esi // low 32 bits of input |
| 50 | shrq $32, %rdi // hi 32 bits of input |
| 51 | orq REL_ADDR(twop84), %rdi // 2^84 + hi (as a double) |
| 52 | orq REL_ADDR(twop52), %rsi // 2^52 + lo (as a double) |
| 53 | movq %rdi, -8(%rsp) |
| 54 | movq %rsi, -16(%rsp) |
| 55 | fldl REL_ADDR(twop84_plus_twop52_neg) |
| 56 | faddl -8(%rsp) // hi - 2^52 (as double extended, no rounding occurs) |
| 57 | faddl -16(%rsp) // hi + lo (as double extended) |
| 58 | ret |
| 59 | |
| 60 | #endif // __x86_64__ |
| 61 | |
| Edward O'Callaghan | eed1300 | 2009-11-04 23:52:51 +0000 | [diff] [blame] | 62 | */ |