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Get codebase completely working with LLVM

Browse Source 
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.
This commit is contained in:
Justine Tunney
2021-02-08 09:19:00 -08:00
parent 0e36cb3ac4
commit e75ffde09e
4528 changed files with 7776 additions and 11640 deletions
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32
libc/nexgen32e/ffs.S
View File

@@ -18,22 +18,22 @@
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/macros.h"
/ Finds lowest set bit in word.
/
/ uint32 𝑥 bsf(𝑥) tzcnt(𝑥) ffs(𝑥) bsr(𝑥) lzcnt(𝑥)
/ 0x00000000 wut 32 0 wut 32
/ 0x00000001 0 0 1 0 31
/ 0x80000001 0 0 1 31 0
/ 0x80000000 31 31 32 31 0
/ 0x00000010 4 4 5 4 27
/ 0x08000010 4 4 5 27 4
/ 0x08000000 27 27 28 27 4
/ 0xffffffff 0 0 1 31 0
/
/ @param edi is the input number
/ @return number in range [1,32] or 0 if no bits set
/ @see also treasure trove of nearly identical functions
/ @asyncsignalsafe
// Finds lowest set bit in word.
//
// uint32 𝑥 bsf(𝑥) tzcnt(𝑥) ffs(𝑥) bsr(𝑥) lzcnt(𝑥)
// 0x00000000 wut 32 0 wut 32
// 0x00000001 0 0 1 0 31
// 0x80000001 0 0 1 31 0
// 0x80000000 31 31 32 31 0
// 0x00000010 4 4 5 4 27
// 0x08000010 4 4 5 27 4
// 0x08000000 27 27 28 27 4
// 0xffffffff 0 0 1 31 0
//
// @param edi is the input number
// @return number in range [1,32] or 0 if no bits set
// @see also treasure trove of nearly identical functions
// @asyncsignalsafe
ffs: .leafprologue
.profilable
or $-1,%edx