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author | Alexey Samsonov <samsonov@google.com> | 2014-02-14 09:20:33 +0000 |
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committer | Alexey Samsonov <samsonov@google.com> | 2014-02-14 09:20:33 +0000 |
commit | 53aa4fda49f94920139300227786ac47c393f1ce (patch) | |
tree | 6d022d04ee279fe1afd89668f346e28a9e3e1559 /lib/builtins/i386/ashrdi3.S | |
parent | 6d999e478fecb10dc43f20b85385d25cc239db0a (diff) |
Move original compiler-rt functions (libgcc replacement) to lib/builtins directory
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@201393 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/builtins/i386/ashrdi3.S')
-rw-r--r-- | lib/builtins/i386/ashrdi3.S | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/lib/builtins/i386/ashrdi3.S b/lib/builtins/i386/ashrdi3.S new file mode 100644 index 000000000..ab0fcfcc9 --- /dev/null +++ b/lib/builtins/i386/ashrdi3.S @@ -0,0 +1,69 @@ +// This file is dual licensed under the MIT and the University of Illinois Open +// Source Licenses. See LICENSE.TXT for details. + +#include "../assembly.h" + +// di_int __ashrdi3(di_int input, int count); + +#ifdef __i386__ +#ifdef __SSE2__ + +.text +.align 4 +DEFINE_COMPILERRT_FUNCTION(__ashrdi3) + movd 12(%esp), %xmm2 // Load count + movl 8(%esp), %eax +#ifndef TRUST_CALLERS_USE_64_BIT_STORES + movd 4(%esp), %xmm0 + movd 8(%esp), %xmm1 + punpckldq %xmm1, %xmm0 // Load input +#else + movq 4(%esp), %xmm0 // Load input +#endif + + psrlq %xmm2, %xmm0 // unsigned shift input by count + + testl %eax, %eax // check the sign-bit of the input + jns 1f // early out for positive inputs + + // If the input is negative, we need to construct the shifted sign bit + // to or into the result, as xmm does not have a signed right shift. + pcmpeqb %xmm1, %xmm1 // -1ULL + psrlq $58, %xmm1 // 0x3f + pandn %xmm1, %xmm2 // 63 - count + pcmpeqb %xmm1, %xmm1 // -1ULL + psubq %xmm1, %xmm2 // 64 - count + psllq %xmm2, %xmm1 // -1 << (64 - count) = leading sign bits + por %xmm1, %xmm0 + + // Move the result back to the general purpose registers and return +1: movd %xmm0, %eax + psrlq $32, %xmm0 + movd %xmm0, %edx + ret +END_COMPILERRT_FUNCTION(__ashrdi3) + +#else // Use GPRs instead of SSE2 instructions, if they aren't available. + +.text +.align 4 +DEFINE_COMPILERRT_FUNCTION(__ashrdi3) + movl 12(%esp), %ecx // Load count + movl 8(%esp), %edx // Load high + movl 4(%esp), %eax // Load low + + testl $0x20, %ecx // If count >= 32 + jnz 1f // goto 1 + + shrdl %cl, %edx, %eax // right shift low by count + sarl %cl, %edx // right shift high by count + ret + +1: movl %edx, %eax // Move high to low + sarl $31, %edx // clear high + sarl %cl, %eax // shift low by count - 32 + ret +END_COMPILERRT_FUNCTION(__ashrdi3) + +#endif // __SSE2__ +#endif // __i386__ |