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- Fix bug in software overflow checking for longint's.

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- AVR: Fix overflow checking for HW multiplications

git-svn-id: trunk@42531 -
This commit is contained in:
Jeppe Johansen 2019-07-30 13:42:26 +00:00
parent dca8147958
commit 1b698d319f
2 changed files with 81 additions and 46 deletions
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125
compiler/avr/cgcpu.pas
View File

@ -1848,44 +1848,31 @@ unit cgcpu;
procedure tcgavr.gen_multiply(list: TAsmList; op: topcg; size: TCgSize; src2, src1, dst: tregister; check_overflow: boolean; var ovloc: tlocation);
procedure perform_r1_check;
procedure perform_r1_check(overflow_label: TAsmLabel; other_reg: TRegister=NR_R1);
var
hl: TAsmLabel;
ai: taicpu;
begin
if check_overflow then
begin
current_asmdata.getjumplabel(hl);
list.concat(taicpu.op_reg_reg(A_AND,NR_R1,NR_R1));
list.concat(taicpu.op_reg_reg(A_OR,NR_R1,other_reg));
ai:=Taicpu.Op_Sym(A_BRxx,hl);
ai.SetCondition(C_EQ);
ai:=Taicpu.Op_Sym(A_BRxx,overflow_label);
ai.SetCondition(C_NE);
ai.is_jmp:=true;
list.concat(ai);
list.concat(taicpu.op_none(A_SET));
a_label(list,hl);
end;
end;
procedure perform_ovf_check;
procedure perform_ovf_check(overflow_label: TAsmLabel);
var
ai: taicpu;
hl: TAsmLabel;
begin
if check_overflow then
begin
current_asmdata.getjumplabel(hl);
ai:=Taicpu.Op_Sym(A_BRxx,hl);
ai.SetCondition(C_CC);
ai:=Taicpu.Op_Sym(A_BRxx,overflow_label);
ai.SetCondition(C_CS);
ai.is_jmp:=true;
list.concat(ai);
list.concat(taicpu.op_none(A_SET));
a_label(list,hl);
end;
end;
@ -1893,15 +1880,14 @@ unit cgcpu;
pd: tprocdef;
paraloc1, paraloc2: tcgpara;
ai: taicpu;
hl: TAsmLabel;
hl, no_overflow: TAsmLabel;
name: String;
begin
ovloc.loc:=LOC_VOID;
if size in [OS_8,OS_S8] then
begin
if (CPUAVR_HAS_MUL in cpu_capabilities[current_settings.cputype]) and
((not check_overflow) or
(size=OS_8)) then
(op=OP_MUL) then
begin
cg.a_reg_alloc(list,NR_R0);
cg.a_reg_alloc(list,NR_R1);
@ -1912,16 +1898,16 @@ unit cgcpu;
current_asmdata.getjumplabel(hl);
list.concat(taicpu.op_reg_reg(A_AND,NR_R1,NR_R1));
{ Clear carry as it's not affected by any of the instructions }
list.concat(taicpu.op_none(A_CLC));
ai:=Taicpu.Op_Sym(A_BRxx,hl);
ai.SetCondition(C_EQ);
ai.is_jmp:=true;
list.concat(ai);
list.concat(taicpu.op_reg(A_CLR,NR_R1));
if op=OP_MUL then
list.concat(taicpu.op_none(A_SEC))
else
list.concat(taicpu.op_none(A_SEV));
list.concat(taicpu.op_none(A_SEC));
a_label(list,hl);
@ -1934,6 +1920,41 @@ unit cgcpu;
list.concat(taicpu.op_reg_reg(A_MOV,dst,NR_R0));
cg.a_reg_dealloc(list,NR_R0);
end
else if (CPUAVR_HAS_MUL in cpu_capabilities[current_settings.cputype]) and
(op=OP_IMUL) then
begin
cg.a_reg_alloc(list,NR_R0);
cg.a_reg_alloc(list,NR_R1);
list.concat(taicpu.op_reg_reg(A_MULS,src1,src2));
list.concat(taicpu.op_reg_reg(A_MOV,dst,NR_R0));
// Check overflow
if check_overflow then
begin
current_asmdata.getjumplabel(no_overflow);
list.concat(taicpu.op_reg_const(A_SBRC,NR_R0,7));
list.concat(taicpu.op_reg(A_INC,NR_R1));
list.concat(taicpu.op_reg(A_TST,NR_R1));
ai:=Taicpu.Op_Sym(A_BRxx,no_overflow);
ai.SetCondition(C_EQ);
ai.is_jmp:=true;
list.concat(ai);
list.concat(taicpu.op_reg(A_CLR,NR_R1));
a_call_name(list,'FPC_OVERFLOW',false);
a_label(list,no_overflow);
ovloc.loc:=LOC_VOID;
end
else
list.concat(taicpu.op_reg(A_CLR,NR_R1));
cg.a_reg_dealloc(list,NR_R1);
cg.a_reg_dealloc(list,NR_R0);
end
else
begin
if size=OS_8 then
@ -1970,52 +1991,66 @@ unit cgcpu;
(size=OS_16)) then
begin
if check_overflow then
list.concat(taicpu.op_none(A_CLT));
begin
current_asmdata.getjumplabel(hl);
current_asmdata.getjumplabel(no_overflow);
end;
cg.a_reg_alloc(list,NR_R0);
cg.a_reg_alloc(list,NR_R1);
list.concat(taicpu.op_reg_reg(A_MUL,src2,src1));
emit_mov(list,dst,NR_R0);
emit_mov(list,GetNextReg(dst),NR_R1);
list.concat(taicpu.op_reg_reg(A_MUL,GetNextReg(src1),src2));
perform_r1_check();
perform_r1_check(hl);
list.concat(taicpu.op_reg_reg(A_ADD,GetNextReg(dst),NR_R0));
perform_ovf_check();
perform_ovf_check(hl);
list.concat(taicpu.op_reg_reg(A_MUL,src1,GetNextReg(src2)));
perform_r1_check();
perform_r1_check(hl);
list.concat(taicpu.op_reg_reg(A_ADD,GetNextReg(dst),NR_R0));
perform_ovf_check();
perform_ovf_check(hl);
if check_overflow then
begin
list.concat(taicpu.op_reg_reg(A_MUL,GetNextReg(src1),GetNextReg(src2)));
perform_r1_check(hl,NR_R0);
end;
cg.a_reg_dealloc(list,NR_R0);
list.concat(taicpu.op_reg(A_CLR,NR_R1));
cg.a_reg_dealloc(list,NR_R1);
if check_overflow then
begin
{
CLC
CLV
BRTC .L1
CLV/CLC
JMP no_overflow
.hl:
CLR R1
SEV/SEC
.L1:
.no_overflow:
}
list.concat(taicpu.op_none(A_CLC));
list.concat(taicpu.op_none(A_CLV));
current_asmdata.getjumplabel(hl);
if op=OP_MUL then
list.concat(taicpu.op_none(A_CLC))
else
list.concat(taicpu.op_none(A_CLV));
ai:=Taicpu.Op_Sym(A_BRxx,hl);
ai.SetCondition(C_TC);
ai.is_jmp:=true;
list.concat(ai);
a_jmp_always(list,no_overflow);
a_label(list,hl);
list.concat(taicpu.op_reg(A_CLR,NR_R1));
if op=OP_MUL then
list.concat(taicpu.op_none(A_SEC))
else
list.concat(taicpu.op_none(A_SEV));
a_label(list,hl);
a_label(list,no_overflow);
ovloc.loc:=LOC_FLAGS;
end;
cg.a_reg_dealloc(list,NR_R1);
end
else
begin

2
rtl/inc/generic.inc
View File

@ -1767,7 +1767,7 @@ end;
((q1>q3) or (q2>q3) or
{ the bit 31 can be only set if we have $8000 0000 }
{ and sign is true }
(q3 shr 15<>0) and
(q3 shr 31<>0) and
((q3<>dword(dword(1) shl 31)) or not(sign))
) then
FPC_Overflow();