cosmopolitan/third_party/compiler_rt/nexgen32e/floatundidf.S
Justine Tunney e75ffde09e Get codebase completely working with LLVM
You can now build Cosmopolitan with Clang:

    make -j8 MODE=llvm
    o/llvm/examples/hello.com

The assembler and linker code is now friendly to LLVM too.
So it's not needed to configure Clang to use binutils under
the hood. If you love LLVM then you can now use pure LLVM.
2021-02-09 02:57:32 -08:00

56 lines
1.4 KiB
ArmAsm

//===-- floatundidf.S - Implement __floatundidf for x86_64 ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements __floatundidf for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
#include "third_party/compiler_rt/assembly.h"
// double __floatundidf(du_int a);
#ifdef __x86_64__
.section .yoink
nopl huge_compiler_rt_license(%rip)
.previous
CONST_SECTION
.balign 16
twop52:
.quad 0x4330000000000000
.balign 16
twop84_plus_twop52:
.quad 0x4530000000100000
.balign 16
twop84:
.quad 0x4530000000000000
#define REL_ADDR(_a) (_a)(%rip)
.text
.balign 4
DEFINE_COMPILERRT_FUNCTION(__floatundidf)
movd %edi, %xmm0 // low 32 bits of a
shrq $32, %rdi // high 32 bits of a
orq REL_ADDR(twop84), %rdi // 0x1p84 + a_hi (no rounding occurs)
orpd REL_ADDR(twop52), %xmm0 // 0x1p52 + a_lo (no rounding occurs)
movd %rdi, %xmm1
subsd REL_ADDR(twop84_plus_twop52), %xmm1 // a_hi - 0x1p52 (no rounding occurs)
addsd %xmm1, %xmm0 // a_hi + a_lo (round happens here)
ret
END_COMPILERRT_FUNCTION(__floatundidf)
#endif // __x86_64__
NO_EXEC_STACK_DIRECTIVE