paweld/fpc
1
0
Fork 0
mirror of https://gitlab.com/freepascal.org/fpc/source.git synced 2025-09-13 10:49:17 +02:00
Code Issues Packages Projects Releases Wiki Activity

+ added explanation for min/max intrinsics

Browse Source 
* prepared x86 implementation for proper NaN handling

git-svn-id: trunk@47715 -
This commit is contained in:
florian 2020-12-07 21:31:07 +00:00
parent 18919b774d
commit 674c3f04e0
2 changed files with 20 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
compiler/compinnr.pas
View File

@ -153,6 +153,17 @@ type
in_fma_double = 134,
in_fma_extended = 135,
in_fma_float128 = 136,
{ the min/max intrinsics must follow the x86 sse
behaviour of min/max regarding handling
NaN: in case of a NaN the result is always the second
operand. This allows a simple translation of
if a>b then result:=a else result:=b;
statements into these intrinsics
The min/max intrinsics are not supposed to
be exposed to the user but only
used internally by the compiler/optimizer }
in_max_single = 137,
in_max_double = 138,
in_min_single = 139,

10
compiler/x86/nx86inl.pas
View File

@ -1479,6 +1479,14 @@ implementation
end;
end;
{ due to min/max behaviour that it loads always the second operand (must be the else assignment) into destination if
one of the operands is a NaN, we cannot swap operands to omit a mova operation in case fastmath is off }
if not(cs_opt_fastmath in current_settings.optimizerswitches) and gotmem and (memop=1) then
begin
hlcg.location_force_mmregscalar(current_asmdata.CurrAsmList,paraarray[1].location,paraarray[1].resultdef,true);
gotmem:=false;
end;
op:=oparray[inlinenumber in [in_max_single,in_max_double],UseAVX,tfloatdef(resultdef).floattype];
location_reset(location,LOC_MMREGISTER,paraarray[1].location.size);
@ -1521,7 +1529,7 @@ implementation
begin
if UseAVX then
emit_reg_reg_reg(op,S_NO,
paraarray[1].location.register,paraarray[2].location.register,location.register)
paraarray[2].location.register,paraarray[1].location.register,location.register)
else
begin
hlcg.a_loadmm_reg_reg(current_asmdata.CurrAsmList,paraarray[1].resultdef,resultdef,