From b2825f24677fe84096cb5a82da55bf707473df44 Mon Sep 17 00:00:00 2001
From: florian <florian@freepascal.org>
Date: Sat, 17 Mar 2018 21:33:07 +0000
Subject: [PATCH] * scale constants if possible before currency multiplications
 to avoid overflows, resolves #33439

git-svn-id: trunk@38555 -
---
 .gitattributes          |  1 +
 compiler/nadd.pas       | 40 +++++++++++++++++++++++++++++++++++++---
 tests/webtbs/tw33439.pp |  9 +++++++++
 3 files changed, 47 insertions(+), 3 deletions(-)
 create mode 100644 tests/webtbs/tw33439.pp

diff --git a/.gitattributes b/.gitattributes
index 0523ff2dae..7866dc5b8b 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -16084,6 +16084,7 @@ tests/webtbs/tw3334.pp svneol=native#text/plain
 tests/webtbs/tw3340.pp svneol=native#text/plain
 tests/webtbs/tw33414.pp svneol=native#text/pascal
 tests/webtbs/tw33417.pp svneol=native#text/pascal
+tests/webtbs/tw33439.pp svneol=native#text/pascal
 tests/webtbs/tw3348.pp svneol=native#text/plain
 tests/webtbs/tw3349.pp svneol=native#text/plain
 tests/webtbs/tw3351.pp svneol=native#text/plain
diff --git a/compiler/nadd.pas b/compiler/nadd.pas
index f009ae9d88..02dfa24415 100644
--- a/compiler/nadd.pas
+++ b/compiler/nadd.pas
@@ -2355,11 +2355,45 @@ implementation
                 end;
               muln :
                 begin
+                  hp:=nil;
                   if s64currencytype.typ=floatdef then
-                    hp:=caddnode.create(slashn,getcopy,crealconstnode.create(10000.0,s64currencytype))
+                    begin
+                      { if left is a currency integer constant, we can get rid of the factor 10000 }
+                      { int64(...) causes a cast on currency, so it is the currency value multiplied by 10000 }
+                      if (left.nodetype=realconstn) and (is_currency(left.resultdef)) and ((int64(trealconstnode(left).value_currency) mod 10000)=0) then
+                        begin
+                          { trealconstnode expects that value_real and value_currency contain valid values }
+                          trealconstnode(left).value_currency:=trealconstnode(left).value_currency {$ifdef FPC_CURRENCY_IS_INT64}div{$else}/{$endif} 10000;
+                          trealconstnode(left).value_real:=trealconstnode(left).value_real/10000;
+                        end
+                      { or if right is an integer constant, we can get rid of its factor 10000 }
+                      else if (right.nodetype=realconstn) and (is_currency(right.resultdef)) and ((int64(trealconstnode(right).value_currency) mod 10000)=0) then
+                        begin
+                          { trealconstnode expects that value and value_currency contain valid values }
+                          trealconstnode(right).value_currency:=trealconstnode(right).value_currency {$ifdef FPC_CURRENCY_IS_INT64}div{$else}/{$endif} 10000;
+                          trealconstnode(right).value_real:=trealconstnode(right).value_real/10000;
+                        end
+                      else
+                        begin
+                          hp:=caddnode.create(slashn,getcopy,crealconstnode.create(10000.0,s64currencytype));
+                          include(hp.flags,nf_is_currency);
+                        end;
+                    end
                   else
-                    hp:=cmoddivnode.create(divn,getcopy,cordconstnode.create(10000,s64currencytype,false));
-                  include(hp.flags,nf_is_currency);
+                    begin
+                      { if left is a currency integer constant, we can get rid of the factor 10000 }
+                      if (left.nodetype=ordconstn) and (is_currency(left.resultdef)) and ((tordconstnode(left).value mod 10000)=0) then
+                        tordconstnode(left).value:=tordconstnode(left).value div 10000
+                      { or if right is an integer constant, we can get rid of its factor 10000 }
+                      else if (right.nodetype=ordconstn) and (is_currency(right.resultdef)) and ((tordconstnode(right).value mod 10000)=0) then
+                        tordconstnode(right).value:=tordconstnode(right).value div 10000
+                      else
+                        begin
+                          hp:=cmoddivnode.create(divn,getcopy,cordconstnode.create(10000,s64currencytype,false));
+                          include(hp.flags,nf_is_currency);
+                        end
+                    end;
+
                   result:=hp
                 end;
             end;
diff --git a/tests/webtbs/tw33439.pp b/tests/webtbs/tw33439.pp
new file mode 100644
index 0000000000..396b20e266
--- /dev/null
+++ b/tests/webtbs/tw33439.pp
@@ -0,0 +1,9 @@
+Var Cur : Currency ;
+
+Begin
+  Cur:=100000000000;
+  Cur:=Cur * 7 ;
+  if Cur<>700000000000 then
+    halt(1);
+  writeln('ok');
+End.