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* i8086 multiplication fixes; 16-bit multiplication now works; 32-bit still doesn't

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git-svn-id: branches/i8086@23795 -
This commit is contained in:
nickysn 2013-03-11 22:31:17 +00:00
parent ee005a9c1b
commit 2872fb95b5
1 changed files with 33 additions and 27 deletions
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60
compiler/i8086/n8086add.pas
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@ -55,18 +55,17 @@ interface
function ti8086addnode.use_generic_mul32to64: boolean;
begin
result := False;
result := True;
end;
{ handles all unsigned multiplications, and 32->64 bit signed ones.
32bit-only signed mul is handled by generic codegen }
{ handles all multiplications }
procedure ti8086addnode.second_addordinal;
var
unsigned: boolean;
begin
unsigned:=not(is_signed(left.resultdef)) or
not(is_signed(right.resultdef));
if (nodetype=muln) and (unsigned or is_64bit(resultdef)) then
if nodetype=muln then
second_mul(unsigned)
else
inherited second_addordinal;
@ -368,6 +367,15 @@ interface
procedure ti8086addnode.second_mul(unsigned: boolean);
procedure add_mov(instr: Taicpu);
begin
{ Notify the register allocator that we have written a move instruction so
it can try to eliminate it. }
if (instr.oper[0]^.reg<>current_procinfo.framepointer) and (instr.oper[0]^.reg<>NR_STACK_POINTER_REG) then
tcgx86(cg).add_move_instruction(instr);
current_asmdata.CurrAsmList.concat(instr);
end;
var reg:Tregister;
ref:Treference;
use_ref:boolean;
@ -382,8 +390,7 @@ interface
{The location.register will be filled in later (JM)}
location_reset(location,LOC_REGISTER,def_cgsize(resultdef));
{ Mul supports registers and references, so if not register/reference,
load the location into a register.
The variant of IMUL which is capable of doing 32->64 bits has the same restrictions. }
load the location into a register. }
use_ref:=false;
if left.location.loc in [LOC_REGISTER,LOC_CREGISTER] then
reg:=left.location.register
@ -399,42 +406,41 @@ interface
reg:=cg.getintregister(current_asmdata.CurrAsmList,OS_INT);
hlcg.a_load_loc_reg(current_asmdata.CurrAsmList,left.resultdef,osuinttype,left.location,reg);
end;
{Allocate EAX.}
cg.getcpuregister(current_asmdata.CurrAsmList,NR_EAX);
{Allocate AX.}
cg.getcpuregister(current_asmdata.CurrAsmList,NR_AX);
{Load the right value.}
hlcg.a_load_loc_reg(current_asmdata.CurrAsmList,right.resultdef,osuinttype,right.location,NR_EAX);
{Also allocate EDX, since it is also modified by a mul (JM).}
cg.getcpuregister(current_asmdata.CurrAsmList,NR_EDX);
hlcg.a_load_loc_reg(current_asmdata.CurrAsmList,right.resultdef,osuinttype,right.location,NR_AX);
{Also allocate DX, since it is also modified by a mul (JM).}
cg.getcpuregister(current_asmdata.CurrAsmList,NR_DX);
if use_ref then
emit_ref(asmops[unsigned],S_L,ref)
emit_ref(asmops[unsigned],S_W,ref)
else
emit_reg(asmops[unsigned],S_L,reg);
emit_reg(asmops[unsigned],S_W,reg);
if (cs_check_overflow in current_settings.localswitches) and
{ 32->64 bit cannot overflow }
(not is_64bit(resultdef)) then
{ 16->32 bit cannot overflow }
(not is_32bitint(resultdef)) then
begin
current_asmdata.getjumplabel(hl4);
cg.a_jmp_flags(current_asmdata.CurrAsmList,F_AE,hl4);
cg.a_call_name(current_asmdata.CurrAsmList,'FPC_OVERFLOW',false);
cg.a_label(current_asmdata.CurrAsmList,hl4);
end;
{Free EAX,EDX}
cg.ungetcpuregister(current_asmdata.CurrAsmList,NR_EDX);
if is_64bit(resultdef) then
{Free AX,DX}
cg.ungetcpuregister(current_asmdata.CurrAsmList,NR_DX);
if is_32bitint(resultdef) then
begin
{Allocate a couple of registers and store EDX:EAX into it}
location.register64.reghi := cg.getintregister(current_asmdata.CurrAsmList,OS_INT);
cg.a_load_reg_reg(current_asmdata.CurrAsmList, OS_INT, OS_INT, NR_EDX, location.register64.reghi);
cg.ungetcpuregister(current_asmdata.CurrAsmList,NR_EAX);
location.register64.reglo := cg.getintregister(current_asmdata.CurrAsmList,OS_INT);
cg.a_load_reg_reg(current_asmdata.CurrAsmList, OS_INT, OS_INT, NR_EAX, location.register64.reglo);
{Allocate an imaginary 32-bit register, which consists of a pair of
16-bit registers and store DX:AX into it}
location.register := cg.getintregister(current_asmdata.CurrAsmList,OS_32);
add_mov(Taicpu.Op_reg_reg(A_MOV,S_W,NR_AX,location.register));
add_mov(Taicpu.Op_reg_reg(A_MOV,S_W,NR_DX,GetNextReg(location.register)));
end
else
begin
{Allocate a new register and store the result in EAX in it.}
{Allocate a new register and store the result in AX in it.}
location.register:=cg.getintregister(current_asmdata.CurrAsmList,OS_INT);
cg.ungetcpuregister(current_asmdata.CurrAsmList,NR_EAX);
cg.a_load_reg_reg(current_asmdata.CurrAsmList,OS_INT,OS_INT,NR_EAX,location.register);
cg.ungetcpuregister(current_asmdata.CurrAsmList,NR_AX);
cg.a_load_reg_reg(current_asmdata.CurrAsmList,OS_INT,OS_INT,NR_AX,location.register);
end;
location_freetemp(current_asmdata.CurrAsmList,left.location);
location_freetemp(current_asmdata.CurrAsmList,right.location);