Defined two new ILI opcodes, IL_PDFIX and IL_PDFIXX. These will be

used to implement the vectorization of IL_DFIX ILIs, i.e. real*8 to
integer*4 type conversions.

Author: gklimowicz

tools/flang2/utils/ilitp/x86_64/ilitp.n

@@ -1295,12 +1295,14 @@ Unsigned integer*8 to real*8 type conversion.
 .CG notAILI
 
 .IL PDFLOATK arlnk xmm nme
-Convert 2 integer*8 values from 'arlnk' into 2 real*8 values in 'xmm'.
+AVX512-DQ instruction to convert packed integer*8 values from 'arlnk'
+into real*8 values in 'xmm'.
 .AT other null trm ssenme
 .CG terminal notAILI
 
 .IL PDFLOATKX xmm xmm
-Convert 2 integer*8 values from 'xmm1' into 2 real*8 values in 'xmm2'.
+AVX512-DQ instruction to convert packed integer*8 values from 'xmm1'
+into real*8 values in 'xmm2'.
 .AT other null trm
 .CG terminal notAILI
 
@@ -1355,6 +1357,18 @@ KIMV combination.
 .AT arth null ir cse
 .CG notCG
 
+.IL PDFIX arlnk xmm nme
+Convert 2 real*8 values from 'arlnk' into 2 integer*4 values in the
+low half of 'xmm'.
+.AT other null trm ssenme
+.CG terminal "cvttpd2dq" avx_special
+
+.IL PDFIXX xmm xmm
+Convert 2 real*8 values from 'xmm1' into 2 integer*4 values in the low
+half of 'xmm2'.
+.AT other null trm
+.CG terminal "cvttpd2dq" avx_special
+
 
 .IL DFIXK dplnk
 Real*8 to to integer*8 type conversion.