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@@ -0,0 +1,73 @@
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+{ %cpu=i386 }
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+{ %opt=-O1r }
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+
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+{$mode delphi}
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+
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+type
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+ my_rec = record
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+ my_field: string;
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+ end;
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+
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+var
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+ my_fyl: my_rec;
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+ my_str: array[0..99] of char;
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+
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+function my_func(var f: my_rec):PChar;
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+begin
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+ my_func:=@my_str[1];
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+end;
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+
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+procedure my_proc(var f: my_rec; const s: String);
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+var i, len: Integer; wascur: PChar;
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+begin
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+ len := length(s);
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+ wascur := my_func(f);
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+ for i:=0 to len-1 do
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+ wascur[i]:=s[i+1];
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+end;
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+
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+begin
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+my_proc(my_fyl,'xxx');
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+my_str[0]:='y';
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+writeln(my_str);
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+end.
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+
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+{
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+It's a spilling bug:
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+
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+# [23] wascur[i]:=s[i+1];
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+ movl -8(%ebp),%ireg23d
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+ # Register %ireg24d allocated
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+ movl %ireg16d,%ireg24d
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+ incl %ireg24d
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+ # Register %ireg24d released
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+ # Register %ireg25d allocated
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+ movl %ireg24d,%ireg25d
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+ # Register %ireg26d allocated
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+ movl -12(%ebp),%ireg26d
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+ # Register %ireg26d released
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+ # Register %edi allocated
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+ leal (%ireg26d,%ireg16d,1),%edi
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+ # Register %ireg23d,%ireg25d released
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+
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+becomes
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+
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+# [23] wascur[i]:=s[i+1];
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+ movl -8(%ebp),%edx
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+ # Register %ecx allocated
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+ movl -20(%ebp),%ecx
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+ incl %ecx
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+ # Register %eax allocated
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+ movl -12(%ebp),%eax
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+ # Register %eax released
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+ # Register %edi,%eax allocated
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+ movl -20(%ebp),%eax
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+ # Register %eax released
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+ leal (%eax,%eax,1),%edi
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+ # Register %edx,%ecx released
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+
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+
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+ireg16d is spilled to -20(%ebp), so before the leal it must be loaded
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+into a register. The spilling code picks eax, but that one is already
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+used at that moment (by ireg26d).
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+}
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peter