ieeeck: use ieee_arithmetic

perazz · Feb 7, 2025 · 9696a00 · 9696a00
1 parent a541801
commit 9696a00
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Showing 2 changed files with 18 additions and 138 deletions.
diff --git a/fypp/src/la_lapack_aux.fypp b/fypp/src/la_lapack_aux.fypp
@@ -2,6 +2,7 @@
 module la_lapack_aux
      use la_constants
      use la_blas
+     use ieee_arithmetic, only: ieee_support_nan, ieee_support_inf
      implicit none(type,external)
      private
 
@@ -249,87 +250,26 @@ module la_lapack_aux
      !> IEEECK: is called from the ILAENV to verify that Infinity and
      !> possibly NaN arithmetic is safe (i.e. will not trap).
 
-     pure integer(ilp)          function la_ieeeck( ispec, zero, one )
+     pure integer(ilp) function la_ieeeck(ispec,zero,one)
         ! -- lapack auxiliary routine --
         ! -- lapack is a software package provided by univ. of tennessee,    --
         ! -- univ. of california berkeley, univ. of colorado denver and nag ltd..--
-           ! Scalar Arguments 
-           integer(ilp), intent(in) :: ispec
-           real(sp), intent(in) :: one, zero
+           ! Scalar Arguments
+           integer(ilp),intent(in) :: ispec
+           real(sp),intent(in) :: one,zero
         ! =====================================================================
-           ! Local Scalars 
-           real(sp) :: nan1, nan2, nan3, nan4, nan5, nan6, neginf, negzro, newzro, posinf
-           ! Executable Statements 
+           ! Executable Statements
            la_ieeeck = 1
-           posinf = one / zero
-           if( posinf<=one ) then
-              la_ieeeck = 0
-              return
-           end if
-           neginf = -one / zero
-           if( neginf>=zero ) then
-              la_ieeeck = 0
-              return
-           end if
-           negzro = one / ( neginf+one )
-           if( negzro/=zero ) then
-              la_ieeeck = 0
-              return
-           end if
-           neginf = one / negzro
-           if( neginf>=zero ) then
-              la_ieeeck = 0
-              return
-           end if
-           newzro = negzro + zero
-           if( newzro/=zero ) then
-              la_ieeeck = 0
-              return
-           end if
-           posinf = one / newzro
-           if( posinf<=one ) then
-              la_ieeeck = 0
-              return
-           end if
-           neginf = neginf*posinf
-           if( neginf>=zero ) then
-              la_ieeeck = 0
-              return
-           end if
-           posinf = posinf*posinf
-           if( posinf<=one ) then
+
+           ! Test support for infinity values
+           if (.not.ieee_support_inf(one)) then 
               la_ieeeck = 0
               return
            end if
+
            ! return if we were only asked to check infinity arithmetic
-           if( ispec==0 )return
-           nan1 = posinf + neginf
-           nan2 = posinf / neginf
-           nan3 = posinf / posinf
-           nan4 = posinf*zero
-           nan5 = neginf*negzro
-           nan6 = nan5*zero
-           if( nan1==nan1 ) then
-              la_ieeeck = 0
-              return
-           end if
-           if( nan2==nan2 ) then
-              la_ieeeck = 0
-              return
-           end if
-           if( nan3==nan3 ) then
-              la_ieeeck = 0
-              return
-           end if
-           if( nan4==nan4 ) then
-              la_ieeeck = 0
-              return
-           end if
-           if( nan5==nan5 ) then
-              la_ieeeck = 0
-              return
-           end if
-           if( nan6==nan6 ) then
+           if (ispec == 0) return
+           if (.not.ieee_support_nan(one)) then
               la_ieeeck = 0
               return
            end if

diff --git a/src/la_lapack_aux.f90 b/src/la_lapack_aux.f90
@@ -1,6 +1,7 @@
 module la_lapack_aux
      use la_constants
      use la_blas
+     use ieee_arithmetic, only: ieee_support_inf, ieee_support_nan
      implicit none(type,external)
      private
 
@@ -239,79 +240,18 @@ pure integer(ilp) function la_ieeeck(ispec,zero,one)
            integer(ilp),intent(in) :: ispec
            real(sp),intent(in) :: one,zero
         ! =====================================================================
-           ! Local Scalars
-           real(sp) :: nan1,nan2,nan3,nan4,nan5,nan6,neginf,negzro,newzro,posinf
            ! Executable Statements
            la_ieeeck = 1
-           posinf = one/zero
-           if (posinf <= one) then
-              la_ieeeck = 0
-              return
-           end if
-           neginf = -one/zero
-           if (neginf >= zero) then
-              la_ieeeck = 0
-              return
-           end if
-           negzro = one/(neginf + one)
-           if (negzro /= zero) then
-              la_ieeeck = 0
-              return
-           end if
-           neginf = one/negzro
-           if (neginf >= zero) then
-              la_ieeeck = 0
-              return
-           end if
-           newzro = negzro + zero
-           if (newzro /= zero) then
-              la_ieeeck = 0
-              return
-           end if
-           posinf = one/newzro
-           if (posinf <= one) then
-              la_ieeeck = 0
-              return
-           end if
-           neginf = neginf*posinf
-           if (neginf >= zero) then
-              la_ieeeck = 0
-              return
-           end if
-           posinf = posinf*posinf
-           if (posinf <= one) then
+
+           ! Test support for infinity values
+           if (.not.ieee_support_inf(one)) then 
               la_ieeeck = 0
               return
            end if
+
            ! return if we were only asked to check infinity arithmetic
            if (ispec == 0) return
-           nan1 = posinf + neginf
-           nan2 = posinf/neginf
-           nan3 = posinf/posinf
-           nan4 = posinf*zero
-           nan5 = neginf*negzro
-           nan6 = nan5*zero
-           if (nan1 == nan1) then
-              la_ieeeck = 0
-              return
-           end if
-           if (nan2 == nan2) then
-              la_ieeeck = 0
-              return
-           end if
-           if (nan3 == nan3) then
-              la_ieeeck = 0
-              return
-           end if
-           if (nan4 == nan4) then
-              la_ieeeck = 0
-              return
-           end if
-           if (nan5 == nan5) then
-              la_ieeeck = 0
-              return
-           end if
-           if (nan6 == nan6) then
+           if (.not.ieee_support_nan(one)) then
               la_ieeeck = 0
               return
            end if