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* -dreplacereg no logner tries to optimize "movl %reg1,%reg1" (which are

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always marked as CanBeRemoved)
  + some comments in -dreplacereg code
  * small fix which could cause crash when optimizer is compiler with -dTP
This commit is contained in:
Jonas Maebe 2000-02-17 07:46:49 +00:00
parent 585796400f
commit aafacbb44b
1 changed files with 25 additions and 6 deletions
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31
compiler/csopt386.pas
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@ -730,14 +730,24 @@ begin
exit;
end;
If tmpResult and
{ don't take into account instructions that will be removed }
{ don't take into account instructions that will be removed }
Not (PPaiProp(endP^.optInfo)^.canBeRemoved) then
begin
{ if the newReg gets stored back to the oldReg, we can change }
{ "mov %oldReg,%newReg; <operations on %newReg>; mov %newReg, }
{ %oldReg" to "<operations on %oldReg>" }
removeLast := storeBack(endP);
sequenceEnd :=
removeLast or
{ no support for (i)div, mul and imul with hardcoded operands }
(noHardCodedRegs(paicpu(endP),orgReg,newReg) and
{ if newReg gets loaded with a new value, we can stop }
{ replacing newReg with oldReg here (possibly keeping }
{ the original contents of oldReg so we still know them }
{ afterwards) }
RegLoadedWithNewValue(newReg,true,paicpu(endP)) or
{ we can also stop if we reached the end of the use of }
{ newReg's current contents }
(GetNextInstruction(endp,hp) and
FindRegDealloc(newReg,hp)));
newRegModified :=
@ -820,7 +830,8 @@ begin
RegLoadedWithNewValue(newReg,true,endP) then
GetLastInstruction(endP,hp)
else hp := endP;
if (p <> endp) or
if removeLast or
(p <> endp) or
not RegLoadedWithNewValue(newReg,true,endP) then
RestoreRegContentsTo(newReg, c ,p, hp);
{ In both case a and b, it is possible that the new register was modified }
@ -1107,10 +1118,11 @@ Begin
{$ifdef replacereg}
top_Reg:
{ try to replace the new reg with the old reg }
if (paicpu(p)^.opcode = A_MOV) and
if not(PPaiProp(p^.optInfo)^.canBeRemoved) and
(paicpu(p)^.opcode = A_MOV) and
getLastInstruction(p,hp4) then
begin
Case paicpu(p)^.oper[1].typ of
case paicpu(p)^.oper[1].typ of
top_Reg:
{ we only have to start replacing from the instruction after the mov, }
{ but replacereg only starts with getnextinstruction(p,p) }
@ -1200,7 +1212,8 @@ begin
{$endif noinstremove}
Begin
{$IfDef TP}
Dispose(PPaiProp(p^.OptInfo));
if assigned(p^.optInfo) then
Dispose(PPaiProp(p^.OptInfo));
{$EndIf TP}
p^.OptInfo := nil;
p := pai(p^.next);;
@ -1221,7 +1234,13 @@ End.
{
$Log$
Revision 1.51 2000-02-12 19:28:56 jonas
Revision 1.52 2000-02-17 07:46:49 jonas
* -dreplacereg no logner tries to optimize "movl %reg1,%reg1" (which are
always marked as CanBeRemoved)
+ some comments in -dreplacereg code
* small fix which could cause crash when optimizer is compiler with -dTP
Revision 1.51 2000/02/12 19:28:56 jonas
* fix for imul optimization in popt386 (exclude top_ref as first
argument)
* in csopt386: change "mov reg1,reg2; <several operations on reg2>;