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* optimized the generated code on i8086 for 64-bit shl/shr with constant >=48

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git-svn-id: trunk@32058 -
This commit is contained in:
nickysn 2015-10-15 15:15:11 +00:00
parent 457107d165
commit 44f6f607c5
1 changed files with 20 additions and 0 deletions
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20
compiler/i8086/n8086mat.pas
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@ -425,6 +425,26 @@ implementation
emit_const_reg(A_RCR,S_W,1,hreg64lo);
end;
end
{ shifting by >=48 }
else if (right.nodetype=ordconstn) and (v>=48) then
begin
if nodetype=shln then
begin
cg.a_load_reg_reg(current_asmdata.CurrAsmList,OS_16,OS_16,hreg64lo,GetNextReg(hreg64hi));
cg.a_load_const_reg(current_asmdata.CurrAsmList,OS_16,0,hreg64lo);
cg.a_load_const_reg(current_asmdata.CurrAsmList,OS_16,0,GetNextReg(hreg64lo));
cg.a_load_const_reg(current_asmdata.CurrAsmList,OS_16,0,hreg64hi);
cg.a_op_const_reg(current_asmdata.CurrAsmList,OP_SHL,OS_16,v-48,GetNextReg(hreg64hi));
end
else
begin
cg.a_load_reg_reg(current_asmdata.CurrAsmList,OS_16,OS_16,GetNextReg(hreg64hi),hreg64lo);
cg.a_load_const_reg(current_asmdata.CurrAsmList,OS_16,0,GetNextReg(hreg64hi));
cg.a_load_const_reg(current_asmdata.CurrAsmList,OS_16,0,hreg64hi);
cg.a_load_const_reg(current_asmdata.CurrAsmList,OS_16,0,GetNextReg(hreg64lo));
cg.a_op_const_reg(current_asmdata.CurrAsmList,OP_SHR,OS_16,v-48,hreg64lo);
end;
end
else
begin
{ load right operators in a register }