0d586d06a7
r303188 removed all the uses of aliases for EABI functions from compiler-rt, because some of them had mismatched calling conventions. Obviously, we can't use aliases for functions which don't have the same calling convention, but that's only an issue for floating-point functions with the hardfloat ABI. In other cases, the stubs increase size and reduce performance for no benefit. This patch adds back the aliases, with appropriate checks to make sure they're only used in cases where the calling convention matches. llvm-svn: 314851
86 lines
2.6 KiB
C
86 lines
2.6 KiB
C
/*===-- floatundisf.c - Implement __floatundisf ---------------------------===
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*
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* The LLVM Compiler Infrastructure
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*
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* This file is dual licensed under the MIT and the University of Illinois Open
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* Source Licenses. See LICENSE.TXT for details.
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*
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* ===----------------------------------------------------------------------===
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*
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* This file implements __floatundisf for the compiler_rt library.
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*
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*===----------------------------------------------------------------------===
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*/
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/* Returns: convert a to a float, rounding toward even. */
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/* Assumption: float is a IEEE 32 bit floating point type
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* du_int is a 64 bit integral type
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*/
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/* seee eeee emmm mmmm mmmm mmmm mmmm mmmm */
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#include "int_lib.h"
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COMPILER_RT_ABI float
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__floatundisf(du_int a)
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{
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if (a == 0)
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return 0.0F;
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const unsigned N = sizeof(du_int) * CHAR_BIT;
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int sd = N - __builtin_clzll(a); /* number of significant digits */
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int e = sd - 1; /* 8 exponent */
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if (sd > FLT_MANT_DIG)
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{
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/* start: 0000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQxxxxxxxxxxxxxxxxxx
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* finish: 000000000000000000000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQR
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* 12345678901234567890123456
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* 1 = msb 1 bit
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* P = bit FLT_MANT_DIG-1 bits to the right of 1
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* Q = bit FLT_MANT_DIG bits to the right of 1
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* R = "or" of all bits to the right of Q
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*/
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switch (sd)
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{
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case FLT_MANT_DIG + 1:
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a <<= 1;
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break;
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case FLT_MANT_DIG + 2:
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break;
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default:
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a = (a >> (sd - (FLT_MANT_DIG+2))) |
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((a & ((du_int)(-1) >> ((N + FLT_MANT_DIG+2) - sd))) != 0);
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};
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/* finish: */
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a |= (a & 4) != 0; /* Or P into R */
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++a; /* round - this step may add a significant bit */
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a >>= 2; /* dump Q and R */
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/* a is now rounded to FLT_MANT_DIG or FLT_MANT_DIG+1 bits */
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if (a & ((du_int)1 << FLT_MANT_DIG))
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{
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a >>= 1;
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++e;
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}
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/* a is now rounded to FLT_MANT_DIG bits */
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}
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else
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{
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a <<= (FLT_MANT_DIG - sd);
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/* a is now rounded to FLT_MANT_DIG bits */
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}
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float_bits fb;
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fb.u = ((e + 127) << 23) | /* exponent */
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((su_int)a & 0x007FFFFF); /* mantissa */
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return fb.f;
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}
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#if defined(__ARM_EABI__)
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#if defined(COMPILER_RT_ARMHF_TARGET)
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AEABI_RTABI float __aeabi_ul2f(du_int a) {
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return __floatundisf(a);
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}
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#else
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AEABI_RTABI float __aeabi_ul2f(du_int a) COMPILER_RT_ALIAS(__floatundisf);
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#endif
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#endif
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