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authorUlrich Drepper <drepper@redhat.com>2005-03-31 10:02:53 +0000
committerUlrich Drepper <drepper@redhat.com>2005-03-31 10:02:53 +0000
commitee6189855aab3a9be8f3c2d95ce2b2cd17db4ec2 (patch)
treecf3e2fe1f9be5b358033fd927a0bd922542e04a1 /sysdeps/ia64/fpu/e_scalb.S
parent4d6302cf51b16a129addf7687c91490c40a7225c (diff)
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* sysdeps/unix/sysv/linux/x86_64/getcontext.S: Use functionally
	equivalent, but shorter instructions.
	* sysdeps/unix/sysv/linux/x86_64/sysdep.h: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/setcontext.S: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/clone.S: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/swapcontext.S: Likewise.
	* sysdeps/unix/x86_64/sysdep.S: Likewise.
	* sysdeps/x86_64/strchr.S: Likewise.
	* sysdeps/x86_64/memset.S: Likewise.
	* sysdeps/x86_64/strcspn.S: Likewise.
	* sysdeps/x86_64/strcmp.S: Likewise.
	* sysdeps/x86_64/elf/start.S: Likewise.
	* sysdeps/x86_64/strspn.S: Likewise.
	* sysdeps/x86_64/dl-machine.h: Likewise.
	* sysdeps/x86_64/bsd-_setjmp.S: Likewise.
	* sysdeps/x86_64/bsd-setjmp.S: Likewise.
	* sysdeps/x86_64/strtok.S: Likewise.
Diffstat (limited to 'sysdeps/ia64/fpu/e_scalb.S')
-rw-r--r--sysdeps/ia64/fpu/e_scalb.S630
1 files changed, 341 insertions, 289 deletions
diff --git a/sysdeps/ia64/fpu/e_scalb.S b/sysdeps/ia64/fpu/e_scalb.S
index 82e914e259..3d48aab189 100644
--- a/sysdeps/ia64/fpu/e_scalb.S
+++ b/sysdeps/ia64/fpu/e_scalb.S
@@ -21,60 +21,82 @@
 // 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 
+// problem reports or change requests be submitted to it directly at
 // http://www.intel.com/software/products/opensource/libraries/num.htm.
 //
 // History
 //==============================================================
 // 02/02/00 Initial version
-// 01/26/01 Scalb completely reworked and now standalone version 
+// 01/26/01 Scalb completely reworked and now standalone version
 // 05/20/02 Cleaned up namespace and sf0 syntax
 // 02/10/03 Reordered header: .section, .global, .proc, .align
+// 08/06/03 Improved performance
 //
 // API
 //==============================================================
-// double = scalb  (double x, double n) 
+// double = scalb  (double x, double n)
 // input  floating point f8 and floating point f9
 // output floating point f8
 //
+// int_type = 0 if int is 32 bits
+// int_type = 1 if int is 64 bits
+//
 // Returns x* 2**n using an fma and detects overflow
-// and underflow.   
+// and underflow.
 //
 //
+// Strategy:
+//  Compute biased exponent of result exp_Result = N + exp_X
+//  Break into ranges:
+//   exp_Result > 0x103fe                 -> Certain overflow
+//   exp_Result = 0x103fe                 -> Possible overflow
+//   0x0fc01 <= exp_Result < 0x103fe      -> No over/underflow (main path)
+//   0x0fc01 - 52 <= exp_Result < 0x0fc01 -> Possible underflow
+//   exp_Result < 0x0fc01 - 52            -> Certain underflow
 
+FR_Big         = f6
+FR_NBig        = f7
 FR_Floating_X  = f8
 FR_Result      = f8
 FR_Floating_N  = f9
 FR_Result2     = f9
-FR_Norm_N      = f10
-FR_Result3     = f11
-FR_Norm_X      = f12
+FR_Result3     = f10
+FR_Norm_X      = f11
+FR_Two_N       = f12
 FR_N_float_int = f13
-FR_Two_N       = f14
-FR_Two_to_Big  = f15
-FR_Big         = f6
-FR_NBig        = f7
+FR_Norm_N      = f14
 
+GR_neg_ov_limit= r14
+GR_big_exp     = r14
 GR_N_Biased    = r15
 GR_Big         = r16
-GR_NBig        = r17
-GR_Scratch     = r18
-GR_Scratch1    = r19
+GR_exp_Result  = r18
+GR_pos_ov_limit= r19
+GR_exp_sure_ou = r19
 GR_Bias        = r20
 GR_N_as_int    = r21
+GR_signexp_X   = r22
+GR_exp_X       = r23
+GR_exp_mask    = r24
+GR_max_exp     = r25
+GR_min_exp     = r26
+GR_min_den_exp = r27
+GR_Scratch     = r28
+GR_signexp_N   = r29
+GR_exp_N       = r30
 
 GR_SAVE_B0          = r32
 GR_SAVE_GP          = r33
@@ -89,412 +111,442 @@ GLOBAL_IEEE754_ENTRY(scalb)
 
 //
 //   Is x NAN, INF, ZERO, +-?
+//   Build the exponent Bias
 //
 {    .mfi
-     alloc          r32=ar.pfs,0,3,4,0
-     fclass.m.unc  p7,p0 = FR_Floating_X, 0xe7 //@snan | @qnan | @inf | @zero
-     addl  GR_Scratch  = 0x019C3F,r0 
+     getf.exp      GR_signexp_N = FR_Floating_N // Get signexp of n
+     fclass.m      p6,p0 = FR_Floating_X, 0xe7  // @snan | @qnan | @inf | @zero
+     mov           GR_Bias = 0x0ffff
+}
+{    .mfi
+     mov           GR_Big = 35000      // If N this big then certain overflow
+     fcvt.fx.trunc.s1   FR_N_float_int = FR_Floating_N // Get N in significand
+     nop.i         0
+}
+;;
+
+{    .mfi
+     getf.exp      GR_signexp_X = FR_Floating_X // Get signexp of x
+     fclass.m      p7,p0 = FR_Floating_N, 0x0b  // Test for n=unorm
+     nop.i         0
 }
 //
-//   Is y a NAN, INF, ZERO, +-?
+//   Normalize n
 //
 {    .mfi
-     nop.m 999
-     fclass.m.unc  p6,p0 = FR_Floating_N, 0xe7 //@snan | @qnan | @inf |  @zero
-     addl  GR_Scratch1  = 0x063BF,r0 
+     mov           GR_exp_mask = 0x1ffff     // Exponent mask
+     fnorm.s1      FR_Norm_N = FR_Floating_N
+     nop.i         0
 }
 ;;
 
 //
-//   Convert N to a fp integer
-//   Normalize x
+//   Is n NAN, INF, ZERO, +-?
 //
 {    .mfi
-     nop.m 0
-     fnorm.s1  FR_Norm_N  =   FR_Floating_N 
-     nop.i 999
+     mov           GR_big_exp = 0x1003e      // Exponent at which n is integer
+     fclass.m      p9,p0 = FR_Floating_N, 0xe7  // @snan | @qnan | @inf | @zero
+     mov           GR_max_exp = 0x103fe      // Exponent of maximum double
 }
-{    .mfi
-     nop.m 999
-     fnorm.s1  FR_Norm_X  =   FR_Floating_X 
-     nop.i 999
-};;
-
 //
-//   Create 2*big
-//   Create 2**-big 
 //   Normalize x
-//   Branch on special values.
 //
-{ .mib
-     setf.exp      FR_Big = GR_Scratch                  
-     nop.i 0 
-(p6) br.cond.spnt  SCALB_NAN_INF_ZERO 
+{ .mfb
+     nop.m         0
+     fnorm.s1      FR_Norm_X = FR_Floating_X
+(p7) br.cond.spnt  SCALB_N_UNORM             // Branch if n=unorm
 }
-{ .mib
-     setf.exp      FR_NBig = GR_Scratch1                  
-     nop.i 0 
-(p7) br.cond.spnt  SCALB_NAN_INF_ZERO 
-};;
+;;
 
-//
-//   Convert N to a fp integer
-//   Create -35000
-//  
+SCALB_COMMON1:
+// Main path continues.  Also return here from u=unorm path.
+//   Handle special cases if x = Nan, Inf, Zero
+{ .mfb
+     nop.m         0
+     fcmp.lt.s1    p7,p0 = FR_Floating_N, f0  // Test N negative
+(p6) br.cond.spnt  SCALB_NAN_INF_ZERO
+}
+;;
+
+//   Handle special cases if n = Nan, Inf, Zero
 {    .mfi
-     addl  GR_Scratch = 1,r0
-     fcvt.fx.trunc.s1   FR_N_float_int = FR_Norm_N 
-     addl    GR_NBig = -35000,r0
+     getf.sig      GR_N_as_int = FR_N_float_int // Get n from significand
+     fclass.m      p8,p0 = FR_Floating_X, 0x0b // Test for x=unorm
+     mov           GR_exp_sure_ou = 0x1000e // Exp_N where x*2^N sure over/under
+}
+{    .mfb
+     mov           GR_min_exp = 0x0fc01      // Exponent of minimum double
+     fcvt.xf       FR_N_float_int = FR_N_float_int // Convert N to FP integer
+(p9) br.cond.spnt  SCALB_NAN_INF_ZERO
 }
 ;;
 
-//
-//   Put N if a GP register
-//   Convert  N_float_int to floating point value
-//   Create 35000
-//   Build the exponent Bias
-//
-{    .mii
-     getf.sig     GR_N_as_int = FR_N_float_int
-     shl   GR_Scratch = GR_Scratch,63
-     addl  GR_Big = 35000,r0
+{    .mmi
+     and           GR_exp_N = GR_exp_mask, GR_signexp_N // Get exponent of N
+(p7) sub           GR_Big = r0, GR_Big          // Limit for N
+     nop.i         0
 }
-{    .mfi
-     addl GR_Bias = 0x0FFFF,r0
-     fcvt.xf  FR_N_float_int = FR_N_float_int
-     nop.i 0
-};;
+;;
 
-//
-//   Catch those fp values that are beyond 2**64-1
-//   Is N > 35000     
-//   Is N < -35000     
-//
-{     .mfi
-     cmp.ne.unc  p9,p10 = GR_N_as_int,GR_Scratch
-     nop.f 0
-     nop.i 0
+{    .mib
+     cmp.lt        p9,p0 = GR_exp_N, GR_big_exp // N possible non-integer?
+     cmp.ge        p6,p0 = GR_exp_N, GR_exp_sure_ou // N certain over/under?
+(p8) br.cond.spnt  SCALB_X_UNORM             // Branch if x=unorm
 }
-{     .mmi
-     cmp.ge.unc p6, p0 = GR_N_as_int, GR_Big
-     cmp.le.unc p8, p0 = GR_N_as_int, GR_NBig
-     nop.i 0
-};;
+;;
 
-//
-//   Is N really an int, only for those non-int indefinites?
-//   Create exp bias.     
-//
-{    .mfi
-     add GR_N_Biased = GR_Bias,GR_N_as_int
-(p9) fcmp.neq.unc.s1 p7,p0  =   FR_Norm_N, FR_N_float_int
-     nop.i 0
-};;
+SCALB_COMMON2:
+// Main path continues.  Also return here from x=unorm path.
+//   Create biased exponent for 2**N
+{    .mmi
+(p6) mov           GR_N_as_int = GR_Big      // Limit N
+;;
+     add           GR_N_Biased = GR_Bias,GR_N_as_int
+     nop.i         0
+}
+;;
 
-//
-//   Branch and return if N is not an int.
-//   Main path, create 2**N
-//
 {    .mfi
-     setf.exp      FR_Two_N = GR_N_Biased                   
-     nop.i                      999
+     setf.exp      FR_Two_N = GR_N_Biased               // Form 2**N
+(p9) fcmp.neq.unc.s1 p9,p0 = FR_Norm_N, FR_N_float_int  // Test if N an integer
+     and           GR_exp_X = GR_exp_mask, GR_signexp_X // Get exponent of X
 }
-{    .mfb
-     nop.m 0
-(p7) frcpa.s0          f8,p11     =    f0,f0
-(p7) br.ret.spnt    b0          
-};;
+;;
 
 //
-//   Set denormal on denormal input x and denormal input N
+//   Compute biased result exponent
+//   Branch if N is not an integer
 //
-{    .mfi
-     nop.m                      999
-(p10)fcmp.ge.s1    p6,p8 = FR_Norm_N,f0
-     nop.i 0
-};;
-{    .mfi
-     nop.m                      999
-     fcmp.ge.s0    p0,p11 = FR_Floating_X,f0
-     nop.i                      999
+{    .mib
+     add           GR_exp_Result = GR_exp_X, GR_N_as_int
+     mov           GR_min_den_exp = 0x0fc01 - 52 // Exponent of min denorm dble
+(p9) br.cond.spnt  SCALB_N_NOT_INT
 }
-{    .mfi
-     nop.m                      999
-     fcmp.ge.s0    p12,p13 = FR_Floating_N,f0
-     nop.i 0
-};;
+;;
 
 //
-//   Adjust 2**N if N was very small or very large
+//   Raise Denormal operand flag with compare
+//   Do final operation
 //
-
 {    .mfi
-     nop.m 0
-(p6) fma.s1  FR_Two_N = FR_Big,f1,f0
-     nop.i 0
+     cmp.lt        p7,p6 = GR_exp_Result, GR_max_exp  // Test no overflow
+     fcmp.ge.s0    p0,p11 = FR_Floating_X,FR_Floating_N  // Dummy to set denorm
+     cmp.lt        p9,p0 = GR_exp_Result, GR_min_den_exp // Test sure underflow
 }
-{ .mlx
-     nop.m 999
-     movl GR_Scratch = 0x00000000000303FF 
-};;
-{    .mfi
-     nop.m 0
-(p8) fma.s1  FR_Two_N = FR_NBig,f1,f0
-     nop.i 0
+{    .mfb
+     nop.m         0
+     fma.d.s0      FR_Result = FR_Two_N,FR_Norm_X,f0
+(p9) br.cond.spnt  SCALB_UNDERFLOW           // Branch if certain underflow
 }
-{    .mlx
-     nop.m 999
-     movl GR_Scratch1= 0x00000000000103FF 
-};;
+;;
+
+{    .mib
+(p6) cmp.gt.unc    p6,p8 = GR_exp_Result, GR_max_exp  // Test sure overflow
+(p7) cmp.ge.unc    p7,p9 = GR_exp_Result, GR_min_exp  // Test no over/underflow
+(p7) br.ret.sptk   b0                         // Return from main path
+}
+;;
 
-//   Set up necessary status fields 
+{    .bbb
+(p6) br.cond.spnt  SCALB_OVERFLOW            // Branch if certain overflow
+(p8) br.cond.spnt  SCALB_POSSIBLE_OVERFLOW   // Branch if possible overflow
+(p9) br.cond.spnt  SCALB_POSSIBLE_UNDERFLOW  // Branch if possible underflow
+}
+;;
+
+// Here if possible underflow.
+// Resulting exponent: 0x0fc01-52 <= exp_Result < 0x0fc01
+SCALB_POSSIBLE_UNDERFLOW:
+//
+// Here if possible overflow.
+// Resulting exponent: 0x103fe = exp_Result
+SCALB_POSSIBLE_OVERFLOW:
+
+//   Set up necessary status fields
 //
 //   S0 user supplied status
 //   S2 user supplied status + WRE + TD  (Overflows)
 //   S3 user supplied status + FZ + TD   (Underflows)
 //
 {    .mfi
-     nop.m 999
-     fsetc.s3 0x7F,0x41
-     nop.i 999
+     mov           GR_pos_ov_limit = 0x103ff // Exponent for positive overflow
+     fsetc.s3      0x7F,0x41
+     nop.i         0
 }
 {    .mfi
-     nop.m 999
-     fsetc.s2 0x7F,0x42
-     nop.i 999
-};;
+     mov           GR_neg_ov_limit = 0x303ff // Exponent for negative overflow
+     fsetc.s2      0x7F,0x42
+     nop.i         0
+}
+;;
 
 //
-//   Do final operation
+//   Do final operation with s2 and s3
 //
 {    .mfi
-     setf.exp FR_NBig = GR_Scratch
-     fma.d.s0     FR_Result = FR_Two_N,FR_Norm_X,f0 
-     nop.i                           999
+     setf.exp      FR_NBig = GR_neg_ov_limit
+     fma.d.s3      FR_Result3 = FR_Two_N,FR_Norm_X,f0
+     nop.i         0
 }
 {    .mfi
-     nop.m                           999
-     fma.d.s3     FR_Result3 = FR_Two_N,FR_Norm_X,f0 
-     nop.i                           999
-};;
-{    .mfi
-     setf.exp FR_Big = GR_Scratch1
-     fma.d.s2     FR_Result2 = FR_Two_N,FR_Norm_X,f0 
-     nop.i                           999
-};;
+     setf.exp      FR_Big = GR_pos_ov_limit
+     fma.d.s2      FR_Result2 = FR_Two_N,FR_Norm_X,f0
+     nop.i         0
+}
+;;
 
 //   Check for overflow or underflow.
-//
-//   S0 user supplied status
-//   S2 user supplied status + WRE + TD  (Overflow)
-//   S3 user supplied status + FZ + TD   (Underflow)
-//
-//
 //   Restore s3
 //   Restore s2
 //
 {    .mfi
-     nop.m 0
-     fsetc.s3 0x7F,0x40
-     nop.i 999 
+     nop.m         0
+     fsetc.s3      0x7F,0x40
+     nop.i         0
 }
 {    .mfi
-     nop.m 0
-     fsetc.s2 0x7F,0x40
-     nop.i 999
-};;
+     nop.m         0
+     fsetc.s2      0x7F,0x40
+     nop.i         0
+}
+;;
 
 //
 //   Is the result zero?
 //
 {    .mfi
-     nop.m 999
-     fclass.m.unc   p6, p0 =  FR_Result3, 0x007
-     nop.i 999 
-} 
+     nop.m         0
+     fclass.m      p6, p0 =  FR_Result3, 0x007
+     nop.i         0
+}
 {    .mfi
-     addl GR_Tag = 53, r0
-     fcmp.ge.unc.s1 p7, p8 = FR_Result2 , FR_Big
-     nop.i 0
-};;
+     nop.m         0
+     fcmp.ge.s1    p7, p8 = FR_Result2 , FR_Big
+     nop.i         0
+}
+;;
 
 //
 //   Detect masked underflow - Tiny + Inexact Only
 //
 {    .mfi
-     nop.m 999
+     nop.m         0
 (p6) fcmp.neq.unc.s1 p6, p0 = FR_Result , FR_Result2
-     nop.i 999 
-};; 
+     nop.i         0
+}
+;;
 
 //
 //   Is result bigger the allowed range?
 //   Branch out for underflow
 //
 {    .mfb
-(p6) addl GR_Tag = 54, r0
+     nop.m          0
 (p8) fcmp.le.unc.s1 p9, p10 = FR_Result2 , FR_NBig
-(p6) br.cond.spnt SCALB_UNDERFLOW 
-};;
+(p6) br.cond.spnt   SCALB_UNDERFLOW
+}
+;;
 
 //
 //   Branch out for overflow
 //
-{ .mbb
-     nop.m 0
-(p7) br.cond.spnt SCALB_OVERFLOW 
-(p9) br.cond.spnt SCALB_OVERFLOW 
-};;
+{ .bbb
+(p7) br.cond.spnt   SCALB_OVERFLOW
+(p9) br.cond.spnt   SCALB_OVERFLOW
+     br.ret.sptk    b0             //   Return from main path.
+}
+;;
 
-//
-//   Return from main path.
-//
-{    .mfb
-     nop.m 999
-     nop.f 0
-     br.ret.sptk     b0;;                   
+// Here if result overflows
+SCALB_OVERFLOW:
+{ .mib
+     alloc         r32=ar.pfs,3,0,4,0
+     addl          GR_Tag = 53, r0     // Set error tag for overflow
+     br.cond.sptk  __libm_error_region // Call error support for overflow
+}
+;;
+
+// Here if result underflows
+SCALB_UNDERFLOW:
+{ .mib
+     alloc         r32=ar.pfs,3,0,4,0
+     addl          GR_Tag = 54, r0     // Set error tag for underflow
+     br.cond.sptk  __libm_error_region // Call error support for underflow
 }
+;;
 
-SCALB_NAN_INF_ZERO: 
+SCALB_NAN_INF_ZERO:
 
 //
-//   Convert N to a fp integer
-//  
+//   Before entry, N has been converted to a fp integer in significand of 
+//     FR_N_float_int
+//
+//   Convert  N_float_int to floating point value
+//
 {    .mfi
-     addl  GR_Scratch = 1,r0
-     fcvt.fx.trunc.s1  FR_N_float_int = FR_Norm_N 
-     nop.i 999
+     getf.sig     GR_N_as_int = FR_N_float_int
+     fclass.m     p6,p0 = FR_Floating_N, 0xc3 //@snan | @qnan
+     nop.i        0
 }
 {    .mfi
-     nop.m 0
-     fclass.m.unc  p6,p0 = FR_Floating_N, 0xc3 //@snan | @qnan 
-     nop.i 0
-};;
+     addl         GR_Scratch = 1,r0
+     fcvt.xf      FR_N_float_int = FR_N_float_int
+     nop.i        0
+}
+;;
+
 {    .mfi
-     nop.m 0
-     fclass.m.unc  p7,p0 = FR_Floating_X, 0xc3 //@snan | @qnan 
-     shl   GR_Scratch = GR_Scratch,63
-};;
+     nop.m        0
+     fclass.m     p7,p0 = FR_Floating_X, 0xc3 //@snan | @qnan
+     shl          GR_Scratch = GR_Scratch,63
+}
+;;
+
 {    .mfi
-     nop.m 0
-     fclass.m.unc  p8,p0 = FR_Floating_N, 0x21 // @inf
-     nop.i 0
-}
-  {  .mfi
-     nop.m 0
-     fclass.m.unc  p9,p0 = FR_Floating_N, 0x22 // @-inf
-     nop.i 0
-};;
+     nop.m        0
+     fclass.m     p8,p0 = FR_Floating_N, 0x21 // @inf
+     nop.i        0
+}
+{    .mfi
+     nop.m        0
+     fclass.m     p9,p0 = FR_Floating_N, 0x22 // @-inf
+     nop.i        0
+}
+;;
 
 //
 //   Either X or N is a Nan, return result and possible raise invalid.
 //
 {    .mfb
-     nop.m 0
-(p6) fma.d.s0     FR_Result = FR_Floating_N,FR_Floating_X,f0 
+     nop.m        0
+(p6) fma.d.s0     FR_Result = FR_Floating_N,FR_Floating_X,f0
 (p6) br.ret.spnt  b0
-};;
+}
+;;
+
 {    .mfb
-     getf.sig     GR_N_as_int = FR_N_float_int
-(p7) fma.d.s0     FR_Result = FR_Floating_N,FR_Floating_X,f0 
+     nop.m        0
+(p7) fma.d.s0     FR_Result = FR_Floating_N,FR_Floating_X,f0
 (p7) br.ret.spnt  b0
-};;
+}
+;;
 
 //
 //   If N + Inf do something special
 //   For N = -Inf, create Int
 //
 {    .mfb
-     nop.m 0
-(p8) fma.d.s0    FR_Result = FR_Floating_X, FR_Floating_N,f0 
-(p8) br.ret.spnt   b0
+     nop.m        0
+(p8) fma.d.s0     FR_Result = FR_Floating_X, FR_Floating_N,f0
+(p8) br.ret.spnt  b0
 }
 {    .mfi
-     nop.m 0
-(p9) fnma.d.s0   FR_Floating_N = FR_Floating_N, f1, f0 
-     nop.i 0
-};;
+     nop.m        0
+(p9) fnma.d.s0    FR_Floating_N = FR_Floating_N, f1, f0
+     nop.i        0
+}
+;;
 
 //
 //   If N==-Inf,return x/(-N)
 //
 {    .mfb
-     nop.m 0
-(p9) frcpa.s0        FR_Result,p6 =  FR_Floating_X,FR_Floating_N
-(p9) br.ret.spnt    b0          
-};;
-
-//
-//   Convert  N_float_int to floating point value
-//
-{     .mfi
-     cmp.ne.unc  p9,p0     =   GR_N_as_int,GR_Scratch
-     fcvt.xf  FR_N_float_int = FR_N_float_int
-     nop.i  0
-};;
+     cmp.ne       p7,p0 = GR_N_as_int,GR_Scratch
+(p9) frcpa.s0     FR_Result,p0 = FR_Floating_X,FR_Floating_N
+(p9) br.ret.spnt  b0
+}
+;;
 
 //
 //   Is N an integer.
 //
 {    .mfi
-     nop.m 0
-(p9) fcmp.neq.unc.s1 p7,p0  =   FR_Norm_N, FR_N_float_int
-     nop.i 0
-};;
+     nop.m        0
+(p7) fcmp.neq.unc.s1 p7,p0 = FR_Norm_N, FR_N_float_int
+     nop.i        0
+}
+;;
 
 //
 //   If N not an int, return NaN and raise invalid.
 //
 {    .mfb
-     nop.m 0
-(p7) frcpa.s0        FR_Result,p6     =    f0,f0
-(p7) br.ret.spnt    b0          
-};;
+     nop.m        0
+(p7) frcpa.s0     FR_Result,p0 = f0,f0
+(p7) br.ret.spnt  b0
+}
+;;
 
 //
-//   Always return x in other path. 
+//   Always return x in other path.
 //
 {    .mfb
-     nop.m 0
-     fma.d.s0      FR_Result = FR_Floating_X,f1,f0 
-     br.ret.sptk   b0
-};;
+     nop.m        0
+     fma.d.s0     FR_Result = FR_Floating_X,f1,f0
+     br.ret.sptk  b0
+}
+;;
 
-GLOBAL_IEEE754_END(scalb)
-__libm_error_region:
+// Here if n not int
+// Return NaN and raise invalid.
+SCALB_N_NOT_INT:
+{    .mfb
+     nop.m        0
+     frcpa.s0     FR_Result,p0 = f0,f0
+     br.ret.sptk  b0
+}
+;;
+
+// Here if n=unorm
+SCALB_N_UNORM:
+{ .mfb
+     getf.exp      GR_signexp_N = FR_Norm_N // Get signexp of normalized n
+     fcvt.fx.trunc.s1   FR_N_float_int = FR_Norm_N // Get N in significand
+     br.cond.sptk  SCALB_COMMON1            // Return to main path
+}
+;;
+
+// Here if x=unorm
+SCALB_X_UNORM:
+{ .mib
+     getf.exp      GR_signexp_X = FR_Norm_X // Get signexp of normalized x
+     nop.i         0
+     br.cond.sptk  SCALB_COMMON2            // Return to main path
+}
+;;
 
-SCALB_OVERFLOW: 
-SCALB_UNDERFLOW: 
+GLOBAL_IEEE754_END(scalb)
+LOCAL_LIBM_ENTRY(__libm_error_region)
 
 //
 // Get stack address of N
 //
 .prologue
 { .mfi
-    add   GR_Parameter_Y=-32,sp         
+    add   GR_Parameter_Y=-32,sp
     nop.f 0
 .save   ar.pfs,GR_SAVE_PFS
-    mov  GR_SAVE_PFS=ar.pfs              
+    mov  GR_SAVE_PFS=ar.pfs
 }
 //
-// Adjust sp 
+// Adjust sp
 //
 { .mfi
 .fframe 64
-   add sp=-64,sp                         
+   add sp=-64,sp
    nop.f 0
-   mov GR_SAVE_GP=gp       
+   mov GR_SAVE_GP=gp
 };;
 
 //
-//  Store N on stack in correct position 
+//  Store N on stack in correct position
 //  Locate the address of x on stack
 //
 { .mmi
-   stfd [GR_Parameter_Y] = FR_Norm_N,16       
-   add GR_Parameter_X = 16,sp          
+   stfd [GR_Parameter_Y] = FR_Norm_N,16
+   add GR_Parameter_X = 16,sp
 .save   b0, GR_SAVE_B0
-   mov GR_SAVE_B0=b0                  
+   mov GR_SAVE_B0=b0
 };;
 
 //
@@ -503,42 +555,42 @@ SCALB_UNDERFLOW:
 //
 .body
 { .mib
-   stfd [GR_Parameter_X] = FR_Norm_X 
-   add   GR_Parameter_RESULT = 0,GR_Parameter_Y   
+   stfd [GR_Parameter_X] = FR_Norm_X
+   add   GR_Parameter_RESULT = 0,GR_Parameter_Y
    nop.b 0
 }
 { .mib
-   stfd [GR_Parameter_Y] = FR_Result                 
+   stfd [GR_Parameter_Y] = FR_Result
    add   GR_Parameter_Y = -16,GR_Parameter_Y
-   br.call.sptk b0=__libm_error_support#   
+   br.call.sptk b0=__libm_error_support#
 };;
 
 //
 //  Get location of result on stack
 //
 { .mmi
+   add   GR_Parameter_RESULT = 48,sp
    nop.m 0
-   nop.m 0
-   add   GR_Parameter_RESULT = 48,sp    
+   nop.i 0
 };;
 
 //
-//  Get the new result 
+//  Get the new result
 //
 { .mmi
-   ldfd  FR_Result = [GR_Parameter_RESULT]      
+   ldfd  FR_Result = [GR_Parameter_RESULT]
 .restore sp
-   add   sp = 64,sp                       
-   mov   b0 = GR_SAVE_B0                  
+   add   sp = 64,sp
+   mov   b0 = GR_SAVE_B0
 };;
 
 //
 //  Restore gp, ar.pfs and return
 //
 { .mib
-   mov   gp = GR_SAVE_GP                  
-   mov   ar.pfs = GR_SAVE_PFS             
-   br.ret.sptk     b0                  
+   mov   gp = GR_SAVE_GP
+   mov   ar.pfs = GR_SAVE_PFS
+   br.ret.sptk     b0
 };;
 
 LOCAL_LIBM_END(__libm_error_region)