+ change always floating point divisions into multiplications if they are a power of two,

  this is an exact operation so it is always allowed
* change only divisions by normal numbers into multiplications

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@29085 3ad0048d-3df7-0310-abae-a5850022a9f2

19 files changed, 99 insertions, 24 deletions

diff --git a/compiler/aarch64/cpuinfo.pas b/compiler/aarch64/cpuinfo.pas
index d67a1e1ce7..d253ed77f4 100644
--- a/compiler/aarch64/cpuinfo.pas
+++ b/compiler/aarch64/cpuinfo.pas
@@ -21,6 +21,9 @@ Interface
 
 Type
    bestreal = double;
+{$if FPC_FULLVERSION>20700}
+   bestrealrec = TDoubleRec;
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = type extended;
diff --git a/compiler/alpha/cpuinfo.pas b/compiler/alpha/cpuinfo.pas
index 0ca4403f6c..cdf5a4ac3f 100644
--- a/compiler/alpha/cpuinfo.pas
+++ b/compiler/alpha/cpuinfo.pas
@@ -41,6 +41,9 @@ Type
    TConstPtrUInt = qword;
 
    bestreal = extended;
+{$if FPC_FULLVERSION>20700}
+   bestrealrec = TExtended80Rec;
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = extended;
diff --git a/compiler/arm/cpuinfo.pas b/compiler/arm/cpuinfo.pas
index 1d0f25816b..05ea89d9e3 100644
--- a/compiler/arm/cpuinfo.pas
+++ b/compiler/arm/cpuinfo.pas
@@ -21,6 +21,9 @@ Interface
 
 Type
    bestreal = double;
+{$if FPC_FULLVERSION>20700}
+   bestrealrec = TDoubleRec;
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = type extended;
diff --git a/compiler/avr/cpuinfo.pas b/compiler/avr/cpuinfo.pas
index 468d1f59e0..eec89b73a2 100644
--- a/compiler/avr/cpuinfo.pas
+++ b/compiler/avr/cpuinfo.pas
@@ -21,6 +21,9 @@ Interface
 
 Type
    bestreal = double;
+{$if FPC_FULLVERSION>20700}
+   bestrealrec = TDoubleRec;
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = type extended;
diff --git a/compiler/generic/cpuinfo.pas b/compiler/generic/cpuinfo.pas
index 05b9407395..c864c8032b 100644
--- a/compiler/generic/cpuinfo.pas
+++ b/compiler/generic/cpuinfo.pas
@@ -22,6 +22,13 @@ Interface
 
 Type
    bestreal = extended;
+{$if FPC_FULLVERSION>20700}
+{$ifdef FPC_HAS_TYPE_EXTENDED}
+   bestrealrec = TExtended80Rec;
+{$else}
+   bestrealrec = TDoubleRec;
+{$endif}
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = type extended;
diff --git a/compiler/globals.pas b/compiler/globals.pas
index cc0df4e2d8..af28bcc9af 100644
--- a/compiler/globals.pas
+++ b/compiler/globals.pas
@@ -84,23 +84,23 @@ interface
        treelogfilename = 'tree.log';
 
 {$if defined(CPUARM) and defined(FPUFPA)}
-       MathQNaN : tdoublerec = (bytes : (0,0,252,255,0,0,0,0));
-       MathInf : tdoublerec = (bytes : (0,0,240,127,0,0,0,0));
-       MathNegInf : tdoublerec = (bytes : (0,0,240,255,0,0,0,0));
-       MathPi : tdoublerec =  (bytes : (251,33,9,64,24,45,68,84));
+       MathQNaN : tcompdoublerec = (bytes : (0,0,252,255,0,0,0,0));
+       MathInf : tcompdoublerec = (bytes : (0,0,240,127,0,0,0,0));
+       MathNegInf : tcompdoublerec = (bytes : (0,0,240,255,0,0,0,0));
+       MathPi : tcompdoublerec =  (bytes : (251,33,9,64,24,45,68,84));
 {$else}
 {$ifdef FPC_LITTLE_ENDIAN}
-       MathQNaN : tdoublerec = (bytes : (0,0,0,0,0,0,252,255));
-       MathInf : tdoublerec = (bytes : (0,0,0,0,0,0,240,127));
-       MathNegInf : tdoublerec = (bytes : (0,0,0,0,0,0,240,255));
-       MathPi : tdoublerec = (bytes : (24,45,68,84,251,33,9,64));
-       MathPiExtended : textendedrec = (bytes : (53,194,104,33,162,218,15,201,0,64));
+       MathQNaN : tcompdoublerec = (bytes : (0,0,0,0,0,0,252,255));
+       MathInf : tcompdoublerec = (bytes : (0,0,0,0,0,0,240,127));
+       MathNegInf : tcompdoublerec = (bytes : (0,0,0,0,0,0,240,255));
+       MathPi : tcompdoublerec = (bytes : (24,45,68,84,251,33,9,64));
+       MathPiExtended : tcompextendedrec = (bytes : (53,194,104,33,162,218,15,201,0,64));
 {$else FPC_LITTLE_ENDIAN}
-       MathQNaN : tdoublerec = (bytes : (255,252,0,0,0,0,0,0));
-       MathInf : tdoublerec = (bytes : (127,240,0,0,0,0,0,0));
-       MathNegInf : tdoublerec = (bytes : (255,240,0,0,0,0,0,0));
-       MathPi : tdoublerec =  (bytes : (64,9,33,251,84,68,45,24));
-       MathPiExtended : textendedrec = (bytes : (64,0,201,15,218,162,33,104,194,53));
+       MathQNaN : tcompdoublerec = (bytes : (255,252,0,0,0,0,0,0));
+       MathInf : tcompdoublerec = (bytes : (127,240,0,0,0,0,0,0));
+       MathNegInf : tcompdoublerec = (bytes : (255,240,0,0,0,0,0,0));
+       MathPi : tcompdoublerec =  (bytes : (64,9,33,251,84,68,45,24));
+       MathPiExtended : tcompextendedrec = (bytes : (64,0,201,15,218,162,33,104,194,53));
 {$endif FPC_LITTLE_ENDIAN}
 {$endif}
 
@@ -963,7 +963,7 @@ implementation
           result := -1;
       end;
 
-    function convertdoublerec(d : tdoublerec) : tdoublerec;{$ifdef USEINLINE}inline;{$endif}
+    function convertdoublerec(d : tcompdoublerec) : tcompdoublerec;{$ifdef USEINLINE}inline;{$endif}
 {$ifdef CPUARM}
       var
         i : longint;
diff --git a/compiler/globtype.pas b/compiler/globtype.pas
index d1879f8cbb..b48a22f7b9 100644
--- a/compiler/globtype.pas
+++ b/compiler/globtype.pas
@@ -110,12 +110,12 @@ interface
 {$endif i8086}
 
        { Use a variant record to be sure that the array if aligned correctly }
-       tdoublerec=record
+       tcompdoublerec=record
          case byte of
            0 : (bytes:array[0..7] of byte);
            1 : (value:double);
        end;
-       textendedrec=record
+       tcompextendedrec=record
          case byte of
            0 : (bytes:array[0..9] of byte);
            1 : (value:extended);
diff --git a/compiler/i386/cpuinfo.pas b/compiler/i386/cpuinfo.pas
index ec8b6d62e1..ced7496d15 100644
--- a/compiler/i386/cpuinfo.pas
+++ b/compiler/i386/cpuinfo.pas
@@ -30,6 +30,9 @@ Interface
 
 Type
    bestreal = extended;
+{$if FPC_FULLVERSION>20700}
+   bestrealrec = TExtended80Rec;
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = extended;
diff --git a/compiler/i8086/cpuinfo.pas b/compiler/i8086/cpuinfo.pas
index d662156c1a..ef971a94ad 100644
--- a/compiler/i8086/cpuinfo.pas
+++ b/compiler/i8086/cpuinfo.pas
@@ -30,6 +30,9 @@ Interface
 
 Type
    bestreal = extended;
+{$if FPC_FULLVERSION>20700}
+   bestrealrec = TExtended80Rec;
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = extended;
diff --git a/compiler/ia64/cpuinfo.pas b/compiler/ia64/cpuinfo.pas
index 03c7ef92bc..5d0a8d0c1b 100644
--- a/compiler/ia64/cpuinfo.pas
+++ b/compiler/ia64/cpuinfo.pas
@@ -30,6 +30,9 @@ uses
 
 Type
    bestreal = extended;
+{$if FPC_FULLVERSION>20700}
+   bestrealrec = TExtended80Rec;
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = extended;
diff --git a/compiler/jvm/cpuinfo.pas b/compiler/jvm/cpuinfo.pas
index 768cc4e9e2..62b89fcd1f 100644
--- a/compiler/jvm/cpuinfo.pas
+++ b/compiler/jvm/cpuinfo.pas
@@ -21,6 +21,9 @@ Interface
 
 Type
    bestreal = double;
+{$if FPC_FULLVERSION>20700}
+   bestrealrec = TDoubleRec;
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = extended;
diff --git a/compiler/m68k/cpuinfo.pas b/compiler/m68k/cpuinfo.pas
index f833eddd6a..80f09b4f29 100644
--- a/compiler/m68k/cpuinfo.pas
+++ b/compiler/m68k/cpuinfo.pas
@@ -21,6 +21,9 @@ Interface
 
 Type
    bestreal = double;
+{$if FPC_FULLVERSION>20700}
+   bestrealrec = TDoubleRec;
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = extended;
diff --git a/compiler/mips/cpuinfo.pas b/compiler/mips/cpuinfo.pas
index b7a6ab86ac..91355b99b1 100644
--- a/compiler/mips/cpuinfo.pas
+++ b/compiler/mips/cpuinfo.pas
@@ -21,6 +21,9 @@ Interface
 
 Type
    bestreal = double;
+{$if FPC_FULLVERSION>20700}
+   bestrealrec = TDoubleRec;
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = type double;
diff --git a/compiler/nadd.pas b/compiler/nadd.pas
index fd3082b978..9424c4e82b 100644
--- a/compiler/nadd.pas
+++ b/compiler/nadd.pas
@@ -684,23 +684,41 @@ implementation
              result:=t;
              exit;
           end;
+{$if FPC_FULLVERSION>20700}
+        { bestrealrec is 2.7.1+ only }
+
+        { replace .../const by a multiplication, but only if fastmath is enabled or
+          the division is done by a power of 2, do not mess with special floating point values like Inf etc.
 
-        { replace .../const by a multiplication, but only if fastmath is enabled,
           do this after constant folding to avoid unnecessary precision loss if
           an slash expresion would be first converted into a multiplication and later
           folded }
         if (nodetype=slashn) and
           { do not mess with currency types }
           (not(is_currency(right.resultdef))) and
-          (cs_opt_fastmath in current_settings.optimizerswitches) then
+          (((cs_opt_fastmath in current_settings.optimizerswitches) and (rt=ordconstn)) or
+           ((cs_opt_fastmath in current_settings.optimizerswitches) and (rt=realconstn) and
+            (bestrealrec(trealconstnode(right).value_real).SpecialType in [fsPositive,fsNegative])
+           ) or
+           ((rt=realconstn) and
+            (bestrealrec(trealconstnode(right).value_real).SpecialType in [fsPositive,fsNegative]) and
+            { mantissa returns the mantissa/fraction without the hidden 1, so power of two means only the hidden
+              bit is set => mantissa must be 0 }
+            (bestrealrec(trealconstnode(right).value_real).Mantissa=0)
+           )
+          ) then
           case rt of
             ordconstn:
               begin
-                nodetype:=muln;
-                t:=crealconstnode.create(1/tordconstnode(right).value,resultdef);
-                right.free;
-                right:=t;
-                exit;
+                { the normal code handles div/0 }
+                if (tordconstnode(right).value<>0) then
+                  begin
+                    nodetype:=muln;
+                    t:=crealconstnode.create(1/tordconstnode(right).value,resultdef);
+                    right.free;
+                    right:=t;
+                    exit;
+                  end;
               end;
             realconstn:
               begin
@@ -709,6 +727,7 @@ implementation
                 exit;
               end;
           end;
+{$endif FPC_FULLVERSION>20700}
 
         { first, we handle widestrings, so we can check later for }
         { stringconstn only                                       }
diff --git a/compiler/powerpc/cpuinfo.pas b/compiler/powerpc/cpuinfo.pas
index 2a3b20d816..ac7b4e3cd1 100644
--- a/compiler/powerpc/cpuinfo.pas
+++ b/compiler/powerpc/cpuinfo.pas
@@ -21,6 +21,9 @@ Interface
 
 Type
    bestreal = double;
+{$if FPC_FULLVERSION>20700}
+   bestrealrec = TDoubleRec;
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = extended;
diff --git a/compiler/powerpc64/cpuinfo.pas b/compiler/powerpc64/cpuinfo.pas
index b50198445b..8d4d636a4f 100644
--- a/compiler/powerpc64/cpuinfo.pas
+++ b/compiler/powerpc64/cpuinfo.pas
@@ -21,6 +21,9 @@ uses
 
 type
   bestreal = double;
+{$if FPC_FULLVERSION>20700}
+  bestrealrec = TDoubleRec;
+{$endif FPC_FULLVERSION>20700}
   ts32real = single;
   ts64real = double;
   ts80real = extended;
diff --git a/compiler/sparc/cpuinfo.pas b/compiler/sparc/cpuinfo.pas
index 3dc03de94b..55c26d3e6c 100644
--- a/compiler/sparc/cpuinfo.pas
+++ b/compiler/sparc/cpuinfo.pas
@@ -30,6 +30,9 @@ uses
 
 type
   bestreal = double;
+{$if FPC_FULLVERSION>20700}
+  bestrealrec = TDoubleRec;
+{$endif FPC_FULLVERSION>20700}
   ts32real = single;
   ts64real = double;
   ts80real = extended;
diff --git a/compiler/vis/cpuinfo.pas b/compiler/vis/cpuinfo.pas
index c33e4e4d3c..ccc3d9bbaa 100644
--- a/compiler/vis/cpuinfo.pas
+++ b/compiler/vis/cpuinfo.pas
@@ -34,6 +34,9 @@ Type
    TConstPtrUInt = Longword;
 
    bestreal = double;
+{$if FPC_FULLVERSION>20700}
+   bestrealrec = TDoubleRec;
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = extended;
diff --git a/compiler/x86_64/cpuinfo.pas b/compiler/x86_64/cpuinfo.pas
index 23ffdfaf49..8dfb941acf 100644
--- a/compiler/x86_64/cpuinfo.pas
+++ b/compiler/x86_64/cpuinfo.pas
@@ -30,6 +30,13 @@ Interface
 
 Type
    bestreal = extended;
+{$if FPC_FULLVERSION>20700}
+{$ifdef FPC_HAS_TYPE_EXTENDED}
+   bestrealrec = TExtended80Rec;
+{$else}
+   bestrealrec = TDoubleRec;
+{$endif}
+{$endif FPC_FULLVERSION>20700}
    ts32real = single;
    ts64real = double;
    ts80real = extended;