re PR fortran/60128 (Wrong ouput using en edit descriptor)

2014-03-08  Dominique d'Humieres  <dominiq@lps.ens.fr>

	PR libgfortran/60128
	* io/write_float.def (output_float): Remove unused variable
	nzero_real. Replace a double space with a single one.
	(determine_en_precision): Fix wrong handling of the EN format.

	PR libfortran/60128
	* gfortran.dg/fmt_en.f90: New test.

From-SVN: r208423

4 files changed, 184 insertions, 22 deletions

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index fb7bf70..e46a9fc 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2014-03-08  Dominique d'Humieres  <dominiq@lps.ens.fr>
+
+	PR libfortran/60128
+	* gfortran.dg/fmt_en.f90: New test.
+
 2014-03-07  Jason Merrill  <jason@redhat.com>
 
 	* lib/g++-dg.exp (g++-dg-runtest): Run tests in C++1y mode, too.
diff --git a/gcc/testsuite/gfortran.dg/fmt_en.f90 b/gcc/testsuite/gfortran.dg/fmt_en.f90
new file mode 100644
index 0000000..75d6040
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/fmt_en.f90
@@ -0,0 +1,141 @@
+! { dg-do run }
+! PR60128 Invalid outputs with EN descriptors
+! Test case provided by Walt Brainerd.
+program pr60128
+implicit none
+    integer :: n_tst = 0, n_cnt = 0
+
+! Original test.
+    call checkfmt("(en15.2)", -.44444,    "    -444.44E-03")
+
+! Test for the bug in comment 6.
+    call checkfmt("(en15.0)", 1.0,        "         1.E+00")
+    call checkfmt("(en15.0)", 1.00000012, "         1.E+00")
+    call checkfmt("(en15.0)", 0.99999994, "         1.E+00")
+    call checkfmt("(en15.0)", 10.0,       "        10.E+00")
+    call checkfmt("(en15.0)", 10.0000010, "        10.E+00")
+    call checkfmt("(en15.0)", 9.99999905, "        10.E+00")
+    call checkfmt("(en15.0)", 100.0,      "       100.E+00")
+    call checkfmt("(en15.0)", 100.000008, "       100.E+00")
+    call checkfmt("(en15.0)", 99.9999924, "       100.E+00")
+    call checkfmt("(en15.0)", 1000.0,     "         1.E+03")
+    call checkfmt("(en15.0)", 1000.00006, "         1.E+03")
+    call checkfmt("(en15.0)", 999.999939, "         1.E+03")
+    call checkfmt("(en15.0)", 9.5,        "        10.E+00")
+    call checkfmt("(en15.0)", 9.50000095, "        10.E+00")
+    call checkfmt("(en15.0)", 9.49999905, "         9.E+00")
+    call checkfmt("(en15.0)", 99.5,       "       100.E+00")
+    call checkfmt("(en15.0)", 99.5000076, "       100.E+00")
+    call checkfmt("(en15.0)", 99.4999924, "        99.E+00")
+    call checkfmt("(en15.0)", 999.5,      "         1.E+03")
+    call checkfmt("(en15.0)", 999.500061, "         1.E+03")
+    call checkfmt("(en15.0)", 999.499939, "       999.E+00")
+    call checkfmt("(en15.0)", 9500.0,     "        10.E+03")
+    call checkfmt("(en15.0)", 9500.00098, "        10.E+03")
+    call checkfmt("(en15.0)", 9499.99902, "         9.E+03")
+    call checkfmt("(en15.1)", 9950.0,     "       10.0E+03")
+    call checkfmt("(en15.2)", 9995.0,     "      10.00E+03")
+    call checkfmt("(en15.3)", 9999.5,     "     10.000E+03")
+    call checkfmt("(en15.1)", 9.5,        "        9.5E+00")
+    call checkfmt("(en15.1)", 9.50000095, "        9.5E+00")
+    call checkfmt("(en15.1)", 9.49999905, "        9.5E+00")
+    call checkfmt("(en15.1)", 0.099951,   "      100.0E-03")
+    call checkfmt("(en15.1)", 0.009951,   "       10.0E-03")
+    call checkfmt("(en15.1)", 0.000999951,"        1.0E-03")
+
+    call checkfmt("(en15.0)", -1.0,        "        -1.E+00")
+    call checkfmt("(en15.0)", -1.00000012, "        -1.E+00")
+    call checkfmt("(en15.0)", -0.99999994, "        -1.E+00")
+    call checkfmt("(en15.0)", -10.0,       "       -10.E+00")
+    call checkfmt("(en15.0)", -10.0000010, "       -10.E+00")
+    call checkfmt("(en15.0)", -9.99999905, "       -10.E+00")
+    call checkfmt("(en15.0)", -100.0,      "      -100.E+00")
+    call checkfmt("(en15.0)", -100.000008, "      -100.E+00")
+    call checkfmt("(en15.0)", -99.9999924, "      -100.E+00")
+    call checkfmt("(en15.0)", -1000.0,     "        -1.E+03")
+    call checkfmt("(en15.0)", -1000.00006, "        -1.E+03")
+    call checkfmt("(en15.0)", -999.999939, "        -1.E+03")
+    call checkfmt("(en15.0)", -9.5,        "       -10.E+00")
+    call checkfmt("(en15.0)", -9.50000095, "       -10.E+00")
+    call checkfmt("(en15.0)", -9.49999905, "        -9.E+00")
+    call checkfmt("(en15.0)", -99.5,       "      -100.E+00")
+    call checkfmt("(en15.0)", -99.5000076, "      -100.E+00")
+    call checkfmt("(en15.0)", -99.4999924, "       -99.E+00")
+    call checkfmt("(en15.0)", -999.5,      "        -1.E+03")
+    call checkfmt("(en15.0)", -999.500061, "        -1.E+03")
+    call checkfmt("(en15.0)", -999.499939, "      -999.E+00")
+    call checkfmt("(en15.0)", -9500.0,     "       -10.E+03")
+    call checkfmt("(en15.0)", -9500.00098, "       -10.E+03")
+    call checkfmt("(en15.0)", -9499.99902, "        -9.E+03")
+    call checkfmt("(en15.1)", -9950.0,     "      -10.0E+03")
+    call checkfmt("(en15.2)", -9995.0,     "     -10.00E+03")
+    call checkfmt("(en15.3)", -9999.5,     "    -10.000E+03")
+    call checkfmt("(en15.1)", -9.5,        "       -9.5E+00")
+    call checkfmt("(en15.1)", -9.50000095, "       -9.5E+00")
+    call checkfmt("(en15.1)", -9.49999905, "       -9.5E+00")
+    call checkfmt("(en15.1)", -0.099951,   "     -100.0E-03")
+    call checkfmt("(en15.1)", -0.009951,   "      -10.0E-03")
+    call checkfmt("(en15.1)", -0.000999951,"       -1.0E-03")
+
+    call checkfmt("(en15.1)", 987350.,     "      987.4E+03")
+    call checkfmt("(en15.2)", 98735.,      "      98.74E+03")
+    call checkfmt("(en15.3)", 9873.5,      "      9.874E+03")
+    call checkfmt("(en15.1)", 987650.,     "      987.6E+03")
+    call checkfmt("(en15.2)", 98765.,      "      98.76E+03")
+    call checkfmt("(en15.3)", 9876.5,      "      9.876E+03")
+    call checkfmt("(en15.1)", 3.125E-02,   "       31.2E-03")
+    call checkfmt("(en15.1)", 9.375E-02,   "       93.8E-03")
+    call checkfmt("(en15.2)", 1.5625E-02,  "      15.62E-03")
+    call checkfmt("(en15.2)", 4.6875E-02,  "      46.88E-03")
+    call checkfmt("(en15.3)", 7.8125E-03,  "      7.812E-03")
+    call checkfmt("(en15.3)", 2.34375E-02, "     23.438E-03")
+    call checkfmt("(en15.3)", 9.765625E-04,"    976.562E-06")
+    call checkfmt("(en15.6)", 2.9296875E-03,"   2.929688E-03")
+
+    call checkfmt("(en15.1)", -987350.,     "     -987.4E+03")
+    call checkfmt("(en15.2)", -98735.,      "     -98.74E+03")
+    call checkfmt("(en15.3)", -9873.5,      "     -9.874E+03")
+    call checkfmt("(en15.1)", -987650.,     "     -987.6E+03")
+    call checkfmt("(en15.2)", -98765.,      "     -98.76E+03")
+    call checkfmt("(en15.3)", -9876.5,      "     -9.876E+03")
+    call checkfmt("(en15.1)", -3.125E-02,   "      -31.2E-03")
+    call checkfmt("(en15.1)", -9.375E-02,   "      -93.8E-03")
+    call checkfmt("(en15.2)", -1.5625E-02,  "     -15.62E-03")
+    call checkfmt("(en15.2)", -4.6875E-02,  "     -46.88E-03")
+    call checkfmt("(en15.3)", -7.8125E-03,  "     -7.812E-03")
+    call checkfmt("(en15.3)", -2.34375E-02, "    -23.438E-03")
+    call checkfmt("(en15.3)", -9.765625E-04,"   -976.562E-06")
+    call checkfmt("(en15.6)", -2.9296875E-03,"  -2.929688E-03")
+
+    !print *, n_tst, n_cnt
+    if (n_cnt /= 0) call abort
+
+contains
+    subroutine checkfmt(fmt, x, cmp)
+        use ISO_FORTRAN_ENV
+        implicit none
+        integer, parameter :: j(size(real_kinds)+4)=[REAL_KINDS, [4, 4, 4, 4]]
+        integer :: i
+        character(len=*), intent(in) :: fmt
+        real, intent(in) :: x
+        character(len=*), intent(in) :: cmp
+        character(len=20) :: s
+        do i=1,size(real_kinds)
+          if (i == 1) then
+            write(s, fmt) real(x,kind=j(1))
+          else if (i == 2) then
+            write(s, fmt) real(x,kind=j(2))
+          else if (i == 3) then
+            write(s, fmt) real(x,kind=j(3))
+          else if (i == 4) then
+            write(s, fmt) real(x,kind=j(4))
+          end if
+          n_tst = n_tst + 1
+          if (s /= cmp) then
+             print "(a,1x,a,' expected: ',1x,a)", fmt, s, cmp
+             n_cnt = n_cnt + 1
+           end if
+        end do
+        
+    end subroutine
+end program
diff --git a/libgfortran/ChangeLog b/libgfortran/ChangeLog
index 0cf04d2..4005df0 100644
--- a/libgfortran/ChangeLog
+++ b/libgfortran/ChangeLog
@@ -1,3 +1,10 @@
+2014-03-08  Dominique d'Humieres  <dominiq@lps.ens.fr>
+
+	PR libgfortran/60128
+	* io/write_float.def (output_float): Remove unused variable
+	nzero_real. Replace a double space with a single one.
+	(determine_en_precision): Fix wrong handling of the EN format.
+
 2014-03-03  Jerry DeLisle  <jvdelisle@gcc.gnu>
 
 	PR libfortran/60148
diff --git a/libgfortran/io/write_float.def b/libgfortran/io/write_float.def
index 59428fc..99f6ff8 100644
--- a/libgfortran/io/write_float.def
+++ b/libgfortran/io/write_float.def
@@ -125,8 +125,6 @@ output_float (st_parameter_dt *dtp, const fnode *f, char *buffer, size_t size,
   int nzero;
   /* Number of digits after the decimal point.  */
   int nafter;
-  /* Number of zeros after the decimal point, whatever the precision.  */
-  int nzero_real;
   int leadzero;
   int nblanks;
   int ndigits, edigits;
@@ -138,7 +136,6 @@ output_float (st_parameter_dt *dtp, const fnode *f, char *buffer, size_t size,
   p = dtp->u.p.scale_factor;
 
   rchar = '5';
-  nzero_real = -1;
 
   /* We should always know the field width and precision.  */
   if (d < 0)
@@ -191,7 +188,7 @@ output_float (st_parameter_dt *dtp, const fnode *f, char *buffer, size_t size,
 	      if (nafter < 0)
 		nafter = 0;
 	      nafter = d;
-	      nzero = nzero_real = 0;
+	      nzero = 0;
 	    }
 	  else /* p < 0  */
 	    {
@@ -211,14 +208,13 @@ output_float (st_parameter_dt *dtp, const fnode *f, char *buffer, size_t size,
 		  nafter = d + nbefore;
 		  nbefore = 0;
 		}
-	      nzero_real = nzero;
 	      if (nzero > d)
 		nzero = d;
 	    }
 	}
       else
 	{
-	  nzero = nzero_real = 0;
+	  nzero = 0;
 	  nafter = d;
 	}
 
@@ -373,7 +369,7 @@ output_float (st_parameter_dt *dtp, const fnode *f, char *buffer, size_t size,
   updown:
 
   rchar = '0';
-  if  (ft != FMT_F && w > 0 && d == 0 && p == 0)
+  if (ft != FMT_F && w > 0 && d == 0 && p == 0)
     nbefore = 1;
   /* Scan for trailing zeros to see if we really need to round it.  */
   for(i = nbefore + nafter; i < ndigits; i++)
@@ -1153,14 +1149,36 @@ OUTPUT_FLOAT_FMT_G(16,L)
 /* EN format is tricky since the number of significant digits depends
    on the magnitude.  Solve it by first printing a temporary value and
    figure out the number of significant digits from the printed
-   exponent.  */
+   exponent.  Values y, 0.95*10.0**e <= y <10.0**e, are rounded to
+   10.0**e even when the final result will not be rounded to 10.0**e.
+   For these values the exponent returned by atoi has to be decremented
+   by one. The values y in the ranges
+       (1000.0-0.5*10.0**(-d))*10.0**(3*n) <= y < 10.0*(3*(n+1))  
+        (100.0-0.5*10.0**(-d))*10.0**(3*n) <= y < 10.0*(3*n+2)
+         (10.0-0.5*10.0**(-d))*10.0**(3*n) <= y < 10.0*(3*n+1)
+   are correctly rounded respectively to 1.0...0*10.0*(3*(n+1)),
+   100.0...0*10.0*(3*n), and 10.0...0*10.0*(3*n), where 0...0
+   represents d zeroes, by the lines 279 to 297. */
 
 #define EN_PREC(x,y)\
 {\
-    GFC_REAL_ ## x tmp;				\
-    tmp = * (GFC_REAL_ ## x *)source;				\
-    if (ISFINITE (y,tmp))					\
-      nprinted = DTOA(y,0,tmp);					\
+    volatile GFC_REAL_ ## x tmp, one = 1.0;\
+    tmp = * (GFC_REAL_ ## x *)source;\
+    if (ISFINITE (y,tmp))\
+      {\
+	nprinted = DTOA(y,0,tmp);\
+	int e = atoi (&buffer[4]);\
+	if (buffer[1] == '1')\
+	  {\
+	    tmp = (calculate_exp_ ## x (-e)) * tmp;\
+	    tmp = one - (tmp < 0 ? -tmp : tmp);	\
+	    if (tmp > 0)\
+	      e = e - 1;\
+	  }\
+	nbefore = e%3;\
+	if (nbefore < 0)\
+	  nbefore = 3 + nbefore;\
+      }\
     else\
       nprinted = -1;\
 }\
@@ -1172,6 +1190,7 @@ determine_en_precision (st_parameter_dt *dtp, const fnode *f,
   int nprinted;
   char buffer[10];
   const size_t size = 10;
+  int nbefore; /* digits before decimal point - 1.  */
 
   switch (len)
     {
@@ -1204,16 +1223,6 @@ determine_en_precision (st_parameter_dt *dtp, const fnode *f,
   if (nprinted == -1)
     return -1;
 
-  int e = atoi (&buffer[5]);
-  int nbefore; /* digits before decimal point - 1.  */
-  if (e >= 0)
-    nbefore = e % 3;
-  else
-    {
-      nbefore = (-e) % 3;
-      if (nbefore != 0)
-	nbefore = 3 - nbefore;
-    }
   int prec = f->u.real.d + nbefore;
   if (dtp->u.p.current_unit->round_status != ROUND_UNSPECIFIED
       && dtp->u.p.current_unit->round_status != ROUND_PROCDEFINED)