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-rw-r--r--sysdeps/ia64/fpu/s_trunc.S207
1 files changed, 86 insertions, 121 deletions
diff --git a/sysdeps/ia64/fpu/s_trunc.S b/sysdeps/ia64/fpu/s_trunc.S
index 0be91200e3..b9ad03b5a8 100644
--- a/sysdeps/ia64/fpu/s_trunc.S
+++ b/sysdeps/ia64/fpu/s_trunc.S
@@ -1,11 +1,10 @@
.file "trunc.s"
-// Copyright (C) 2000, 2001, Intel Corporation
+
+// Copyright (c) 2000 - 2003, Intel Corporation
// All rights reserved.
-//
-// Contributed 7/7/2000 by John Harrison, Cristina Iordache, Ted Kubaska,
-// Bob Norin, Shane Story, and Ping Tak Peter Tang of the
-// Computational Software Lab, Intel Corporation.
+//
+// Contributed 2000 by the Intel Numerics Group, Intel Corporation
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
@@ -21,33 +20,28 @@
// * The name of Intel Corporation may not be used to endorse or promote
// products derived from this software without specific prior written
// permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR ITS
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR ITS
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
-// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
-// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
-// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
// OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY OR TORT (INCLUDING
-// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
-// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-//
+// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
// Intel Corporation is the author of this code, and requests that all
-// problem reports or change requests be submitted to it directly at
-// http://developer.intel.com/opensource.
+// problem reports or change requests be submitted to it directly at
+// http://www.intel.com/software/products/opensource/libraries/num.htm.
//
-.align 32
-.global trunc#
-
-.section .text
-.proc trunc#
-.align 32
-
// History
//==============================================================
-// 7/7/00: Created
+// 07/07/00 Created
+// 05/20/02 Cleaned up namespace and sf0 syntax
+// 01/20/03 Improved performance and reduced code size
//==============================================================
// API
@@ -55,25 +49,28 @@
// double trunc(double x)
//==============================================================
-#include "libm_support.h"
+// general input registers:
+// r14 - r18
-// general input registers:
-TRUNC_GR_FFFF = r14
-TRUNC_GR_signexp = r15
-TRUNC_GR_exponent = r16
-TRUNC_GR_expmask = r17
-TRUNC_GR_bigexp = r18
+rExpBias = r14
+rSignexp = r15
+rExp = r16
+rExpMask = r17
+rBigexp = r18
// floating-point registers:
-// f8, f9, f11, f12
+// f8 - f10
+
+fXtruncInt = f9
+fNormX = f10
-// predicate registers used:
-// p6, p7, p8, p9, p10, p11
+// predicate registers used:
+// p6, p7
// Overview of operation
//==============================================================
// double trunc(double x)
-// Return an integer value (represented as a double) less than or
+// Return an integer value (represented as a double) less than or
// equal to x in magnitude.
// This is x rounded toward zero to an integral value.
//==============================================================
@@ -97,105 +94,73 @@ TRUNC_GR_bigexp = r18
// If we multiply by 2^23, we no longer have a fractional part
// So input is an integer value already.
-trunc:
+.section .text
+GLOBAL_LIBM_ENTRY(trunc)
{ .mfi
- getf.exp TRUNC_GR_signexp = f8
- fcvt.fx.trunc.s1 f9 = f8
- addl TRUNC_GR_bigexp = 0x10033, r0
+ getf.exp rSignexp = f8 // Get signexp, recompute if unorm
+ fcvt.fx.trunc.s1 fXtruncInt = f8 // Convert to int in significand
+ addl rBigexp = 0x10033, r0 // Set exponent at which is integer
}
{ .mfi
- mov TRUNC_GR_FFFF = 0x0FFFF
- fnorm.d f11 = f8
- mov TRUNC_GR_expmask = 0x1FFFF
-};;
-// get the exponent of x
-// convert x to integer in signficand of f9
-// Normalize x - this will raise invalid on SNaNs, the
-// denormal operand flag - and possibly a spurious U flag
-// get exponent only mask (will exclude sign bit)
+ mov rExpBias = 0x0FFFF // Form exponent bias
+ fnorm.s1 fNormX = f8 // Normalize input
+ mov rExpMask = 0x1FFFF // Form exponent mask
+}
+;;
{ .mfi
nop.m 0
- fclass.m p7,p8 = f8, 0x0b
+ fclass.m p7,p0 = f8, 0x0b // Test x unorm
nop.i 0
}
-{ .mfi
- nop.m 0
- fcmp.eq.unc.s1 p9,p0 = f8,f0
- nop.i 0
-};;
-// fclass to set p7 if unnorm
-{ .mmi
- and TRUNC_GR_exponent = TRUNC_GR_signexp, TRUNC_GR_expmask ;;
-(p8) cmp.ge.unc p10,p11 = TRUNC_GR_exponent, TRUNC_GR_bigexp
-(p8) cmp.ne.unc p6,p0 = TRUNC_GR_exponent, TRUNC_GR_signexp
-};;
-// Get the exponent of x
-// Test if exponent such that result already an integer
-// Test if x < 0
-{ .mmi
-(p9) cmp.eq.andcm p10,p11 = r0, r0
-(p6) cmp.lt.unc p6,p0 = TRUNC_GR_exponent, TRUNC_GR_FFFF
- nop.i 0
-};;
-// If -1 < x < 0, set p6, turn off p10 and p11, and set result to -0.0
-{ .mfb
-(p6) cmp.eq.andcm p10,p11 = r0, r0
-(p6) fmerge.s f8 = f8, f0
- nop.b 0
-};;
-// If not a unnorm, set p10 if x already is a big int, nan, or inf?
-// If not a unnorm, set p10 if x already is a big int, nan, or inf?
-.pred.rel "mutex",p10,p11
+;;
+
{ .mfb
nop.m 0
-(p11) fcvt.xf f8 = f9
- nop.b 0
+ fclass.m p6,p0 = f8, 0x1e3 // Test x natval, nan, inf
+(p7) br.cond.spnt TRUNC_UNORM // Branch if x unorm
}
+;;
+
+TRUNC_COMMON:
+// Return here from TRUNC_UNORM
{ .mfb
+ and rExp = rSignexp, rExpMask // Get biased exponent
+(p6) fma.d.s0 f8 = f8, f1, f0 // Result if x natval, nan, inf
+(p6) br.ret.spnt b0 // Exit if x natval, nan, inf
+}
+;;
+
+{ .mfi
+ cmp.lt p6,p0 = rExp, rExpBias // Is |x| < 1?
+ fcvt.xf f8 = fXtruncInt // Result, assume 1 <= |x| < 2^52
+ cmp.ge p7,p0 = rExp, rBigexp // Is |x| >= 2^52?
+}
+;;
+
+// We must correct result if |x| < 1, or |x| >= 2^52
+.pred.rel "mutex",p6,p7
+{ .mfi
nop.m 0
-(p10) fma.d.s1 f8 = f11,f1,f0
-(p8) br.ret.sptk b0
-};;
-// If not a unnorm and not an big int, nan,or +/-inf convert signficand
-// back to f8.
-// If not a unorm and a big int, nan, or +/-inf, return fnorm'd x
-// If not a unorm, Return
-// If unnorm, get the exponent again - perhaps it wasn't a denorm.
-{ .mfb
-(p7) getf.exp TRUNC_GR_signexp = f11
-(p7) fcvt.fx.trunc.s1 f12 = f11
- nop.b 0
-};;
-{ .mfb
- and TRUNC_GR_exponent = TRUNC_GR_signexp, TRUNC_GR_expmask
- fcmp.lt.unc.s1 p9,p0 = f8,f0
- nop.b 0
-};;
-{ .mfb
- cmp.ge.unc p10,p11 = TRUNC_GR_exponent, TRUNC_GR_bigexp
- nop.f 0
- nop.b 0
-};;
-// If a unnorm, check to see if value is already a big int.
+(p6) fmerge.s f8 = fNormX, f0 // If |x| < 1, result sgn(x)*0
+ nop.i 0
+}
{ .mfb
- nop.m 0
-(p11) fcvt.xf f8 = f12
- nop.b 0
+ nop.m 0
+(p7) fma.d.s0 f8 = fNormX, f1, f0 // If |x| >= 2^52, result x
+ br.ret.sptk b0 // Exit main path
}
-{ .mfi
- nop.m 0
-(p10) fma.d.s1 f8 = f11,f1,f0
- nop.i 0
-};;
+;;
+
+
+TRUNC_UNORM:
+// Here if x unorm
{ .mfb
- nop.m 0
-(p9) fmerge.ns f8 = f1,f8
- br.ret.sptk b0
-};;
-// If so return it. Otherwise, return (fcvt.xf(fcvt.fx.trunc(x)))
-// Make sure the result is negative if it should be - that is
-// negative(denormal) -> -0.
-.endp trunc
-ASM_SIZE_DIRECTIVE(trunc)
+ getf.exp rSignexp = fNormX // Get signexp, recompute if unorm
+ fcmp.eq.s0 p7,p0 = f8, f0 // Dummy op to set denormal flag
+ br.cond.sptk TRUNC_COMMON // Return to main path
+}
+;;
+
+GLOBAL_LIBM_END(trunc)