* only remove the calculation of unused parameters of inline routines if

    they don't have explicit side-effects, and if -Oodeadvalues (part of -O4)
    is active (because it can result in the removal of range check errors,
    segmentation faults, etc)

git-svn-id: trunk@22254 -

.gitattributes

@@ -9610,6 +9610,8 @@ tests/tbs/tb0579.pp svneol=native#text/pascal
 tests/tbs/tb0580.pp svneol=native#text/pascal
 tests/tbs/tb0581.pp svneol=native#text/plain
 tests/tbs/tb0582.pp svneol=native#text/pascal
+tests/tbs/tb0583.pp svneol=native#text/plain
+tests/tbs/tb0583a.pp svneol=native#text/plain
 tests/tbs/tb205.pp svneol=native#text/plain
 tests/tbs/ub0060.pp svneol=native#text/plain
 tests/tbs/ub0069.pp svneol=native#text/plain

compiler/globtype.pas

@@ -244,7 +244,15 @@ interface
          cs_opt_regvar,cs_opt_uncertain,cs_opt_size,cs_opt_stackframe,
          cs_opt_peephole,cs_opt_asmcse,cs_opt_loopunroll,cs_opt_tailrecursion,cs_opt_nodecse,
          cs_opt_nodedfa,cs_opt_loopstrength,cs_opt_scheduler,cs_opt_autoinline,cs_useebp,
-         cs_opt_reorder_fields,cs_opt_fastmath
+         cs_opt_reorder_fields,cs_opt_fastmath,
+         { Allow removing expressions whose result is not used, even when this
+           can change program behaviour (range check errors disappear,
+           access violations due to invalid pointer derefences disappear, ...).
+           Note: it does not (and must not) remove expressions that have
+             explicit side-effects, only implicit side-effects (like the ones
+             mentioned before) can disappear.
+         }
+         cs_opt_dead_values
        );
        toptimizerswitches = set of toptimizerswitch;
 
@@ -269,7 +277,7 @@ interface
          'REGVAR','UNCERTAIN','SIZE','STACKFRAME',
          'PEEPHOLE','ASMCSE','LOOPUNROLL','TAILREC','CSE',
          'DFA','STRENGTH','SCHEDULE','AUTOINLINE','USEEBP',
-         'ORDERFIELDS','FASTMATH'
+         'ORDERFIELDS','FASTMATH','DEADVALUES'
        );
        WPOptimizerSwitchStr : array [twpoptimizerswitch] of string[14] = (
          'DEVIRTCALLS','OPTVMTS','SYMBOLLIVENESS'
@@ -287,7 +295,7 @@ interface
        genericlevel1optimizerswitches = [cs_opt_level1];
        genericlevel2optimizerswitches = [cs_opt_level2];
        genericlevel3optimizerswitches = [cs_opt_level3];
-       genericlevel4optimizerswitches = [cs_opt_reorder_fields];
+       genericlevel4optimizerswitches = [cs_opt_reorder_fields,cs_opt_dead_values];
 
        { whole program optimizations whose information generation requires
          information from all loaded units

compiler/ncal.pas

@@ -3717,7 +3717,10 @@ implementation
         para := tcallparanode(left);
         while assigned(para) do
           begin
-            if (para.parasym.typ = paravarsym) and (para.parasym.refs>0) then
+            if (para.parasym.typ = paravarsym) and
+               ((para.parasym.refs>0) or
+                not(cs_opt_dead_values in current_settings.optimizerswitches) or
+                might_have_sideeffects(para.left)) then
               begin
                 { must take copy of para.left, because if it contains a       }
                 { temprefn pointing to a copied temp (e.g. methodpointer),    }

tests/tbs/tb0583.pp

@@ -0,0 +1,17 @@
+{ %opt=-O-3 }
+{ %result=201 }
+
+{$inline on}
+{$r+}
+
+procedure test(l: longint); inline;
+begin
+end;
+
+var
+  a: array[0..0] of byte;
+  i: longint;
+begin
+  i:=1345;
+  test(a[i]);
+end.

tests/tbs/tb0583a.pp

@@ -0,0 +1,24 @@
+{ %opt=-O-4 }
+{ %result=201 }
+
+{$inline on}
+{$r+}
+
+var
+  l: longint;
+
+function f: longint;
+begin
+  l:=5;
+  f:=2;
+end;
+
+procedure test(l: longint); inline;
+begin
+end;
+
+var
+  a: array[0..0] of byte;
+begin
+  test(a[f]);
+end.