[TTI][AArch64][CostModel] Adjusting the cost of vector element insert/extract operations for ARM based Apple CPUs

[nilanjana_basu]

Summary

This recovers an SLP regression revealed by D146033 while showing a maximum performance lift of 4% on some other benchmarks.

llvm/lib/Target/AArch64/AArch64Subtarget.cpp

case AppleA16:
     CacheLineSize = 64;
     PrefetchDistance = 280;
     MinPrefetchStride = 2048;
     MaxPrefetchIterationsAhead = 3;
     switch (ARMProcFamily) {
     case AppleA14:
     case AppleA15:
     case AppleA16:
+      VectorInsertExtractBaseCost=2;
       MaxInterleaveFactor = 4;
       break;
     default:
       break;
     }
     break;
   case ExynosM3:
     MaxInterleaveFactor = 4;

llvm/test/Analysis/CostModel/AArch64/insert-extract.ll

 ; NEO-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %t120 = insertelement <4 x half> zeroinitializer, half 0xH0000, i64 1
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: %t130 = insertelement <2 x float> zeroinitializer, float 0.000000e+00, i64 0
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %t140 = insertelement <2 x float> zeroinitializer, float 0.000000e+00, i64 1
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: %t150 = insertelement <2 x double> zeroinitializer, double 0.000000e+00, i64 0
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %t160 = insertelement <2 x double> zeroinitializer, double 0.000000e+00, i64 1
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret void
 ;
 ; AA14-LABEL: 'vectorInstrCost':
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t1 = extractelement <8 x i8> undef, i32 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t2 = extractelement <8 x i8> undef, i32 1
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t3 = extractelement <4 x i16> undef, i32 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t4 = extractelement <4 x i16> undef, i32 1
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t5 = extractelement <2 x i32> undef, i32 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t6 = extractelement <2 x i32> undef, i32 1
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t7 = extractelement <2 x i64> undef, i32 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t8 = extractelement <2 x i64> undef, i32 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t1 = extractelement <8 x i8> undef, i32 0
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t2 = extractelement <8 x i8> undef, i32 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t3 = extractelement <4 x i16> undef, i32 0
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t4 = extractelement <4 x i16> undef, i32 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t5 = extractelement <2 x i32> undef, i32 0
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t6 = extractelement <2 x i32> undef, i32 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t7 = extractelement <2 x i64> undef, i32 0
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t8 = extractelement <2 x i64> undef, i32 1
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 0 for instruction:   %t9 = extractelement <4 x half> undef, i32 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t10 = extractelement <4 x half> undef, i32 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t10 = extractelement <4 x half> undef, i32 1
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 0 for instruction:   %t11 = extractelement <2 x float> undef, i32 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t12 = extractelement <2 x float> undef, i32 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t12 = extractelement <2 x float> undef, i32 1
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 0 for instruction:   %t13 = extractelement <2 x double> undef, i32 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t14 = extractelement <2 x double> undef, i32 1
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t30 = insertelement <8 x i8> undef, i8 0, i32 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t40 = insertelement <8 x i8> undef, i8 1, i32 1
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t50 = insertelement <4 x i16> undef, i16 2, i32 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t60 = insertelement <4 x i16> undef, i16 3, i32 1
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t70 = insertelement <2 x i32> undef, i32 4, i32 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t80 = insertelement <2 x i32> undef, i32 5, i32 1
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t90 = insertelement <2 x i64> undef, i64 6, i32 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t100 = insertelement <2 x i64> undef, i64 7, i32 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t14 = extractelement <2 x double> undef, i32 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t30 = insertelement <8 x i8> undef, i8 0, i32 0
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t40 = insertelement <8 x i8> undef, i8 1, i32 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t50 = insertelement <4 x i16> undef, i16 2, i32 0
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t60 = insertelement <4 x i16> undef, i16 3, i32 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t70 = insertelement <2 x i32> undef, i32 4, i32 0
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t80 = insertelement <2 x i32> undef, i32 5, i32 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t90 = insertelement <2 x i64> undef, i64 6, i32 0
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t100 = insertelement <2 x i64> undef, i64 7, i32 1
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 0 for instruction:   %t110 = insertelement <4 x half> zeroinitializer, half 0xH0000, i64 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t120 = insertelement <4 x half> zeroinitializer, half 0xH0000, i64 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t120 = insertelement <4 x half> zeroinitializer, half 0xH0000, i64 1
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 0 for instruction:   %t130 = insertelement <2 x float> zeroinitializer, float 0.000000e+00, i64 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t140 = insertelement <2 x float> zeroinitializer, float 0.000000e+00, i64 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t140 = insertelement <2 x float> zeroinitializer, float 0.000000e+00, i64 1
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 0 for instruction:   %t150 = insertelement <2 x double> zeroinitializer, double 0.000000e+00, i64 0
-; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %t160 = insertelement <2 x double> zeroinitializer, double 0.000000e+00, i64 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 2 for instruction:   %t160 = insertelement <2 x double> zeroinitializer, double 0.000000e+00, i64 1
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 0 for instruction:   ret void
 ;
   %t1 = extractelement <8 x i8> undef, i32 0
   %t2 = extractelement <8 x i8> undef, i32 1
   %t3 = extractelement <4 x i16> undef, i32 0
   %t4 = extractelement <4 x i16> undef, i32 1
   %t5 = extractelement <2 x i32> undef, i32 0
   %t6 = extractelement <2 x i32> undef, i32 1

 ;
 ; NEO-LABEL: 'LD1_B'
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v1 = load i8, ptr %i, align 1
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %v2 = insertelement <8 x i8> %vec, i8 %v1, i32 1
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret <8 x i8> %v2
 ;
 ; AA14-LABEL: 'LD1_B':
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 1 for instruction:   %v1 = load i8, ptr %i, align 1
-; AA14-NEXT:  Cost Model: Found an estimated cost of 4 for instruction:   %v2 = insertelement <8 x i8> %vec, i8 %v1, i32 1
+; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %v2 = insertelement <8 x i8> %vec, i8 %v1, i32 1
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 0 for instruction:   ret <8 x i8> %v2
 ;
 entry:
   %v1 = load i8, ptr %i, align 1
   %v2 = insertelement <8 x i8> %vec, i8 %v1, i32 1
   ret <8x i8> %v2
 }
 
 define <4 x i16> @LD1_H(<4 x i16> %vec, ptr noundef %i) {
 ; KRYO-LABEL: 'LD1_H'
 ; KRYO-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v1 = load i16, ptr %i, align 2
 ; KRYO-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %v2 = insertelement <4 x i16> %vec, i16 %v1, i32 2
 ; KRYO-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret <4 x i16> %v2
 ;
 ; NEO-LABEL: 'LD1_H'
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v1 = load i16, ptr %i, align 2
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %v2 = insertelement <4 x i16> %vec, i16 %v1, i32 2
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret <4 x i16> %v2
 ;
 ; AA14-LABEL: 'LD1_H':
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 1 for instruction:   %v1 = load i16, ptr %i, align 2
-; AA14-NEXT:  Cost Model: Found an estimated cost of 4 for instruction:   %v2 = insertelement <4 x i16> %vec, i16 %v1, i32 2
+; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %v2 = insertelement <4 x i16> %vec, i16 %v1, i32 2
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 0 for instruction:   ret <4 x i16> %v2
 ;
 entry:
   %v1 = load i16, ptr %i, align 2
   %v2 = insertelement <4 x i16> %vec, i16 %v1, i32 2
   ret <4 x i16> %v2
 }
 
 define <4 x i32> @LD1_W(<4 x i32> %vec, ptr noundef %i) {
 ; KRYO-LABEL: 'LD1_W'
 ; KRYO-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v1 = load i32, ptr %i, align 4
 ; KRYO-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %v2 = insertelement <4 x i32> %vec, i32 %v1, i32 3
 ; KRYO-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret <4 x i32> %v2
 ;
 ; NEO-LABEL: 'LD1_W'
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v1 = load i32, ptr %i, align 4
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %v2 = insertelement <4 x i32> %vec, i32 %v1, i32 3
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret <4 x i32> %v2
 ;
 ; AA14-LABEL: 'LD1_W':
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 1 for instruction:   %v1 = load i32, ptr %i, align 4
-; AA14-NEXT:  Cost Model: Found an estimated cost of 4 for instruction:   %v2 = insertelement <4 x i32> %vec, i32 %v1, i32 3
+; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %v2 = insertelement <4 x i32> %vec, i32 %v1, i32 3
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 0 for instruction:   ret <4 x i32> %v2
 ;
 entry:
   %v1 = load i32, ptr %i, align 4
   %v2 = insertelement <4 x i32> %vec, i32 %v1, i32 3
   ret <4 x i32> %v2
 }
 
 define <2 x i64> @LD1_X(<2 x i64> %vec, ptr noundef %i) {
 ; KRYO-LABEL: 'LD1_X'
 ; KRYO-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v1 = load i64, ptr %i, align 8
 ; KRYO-NEXT:  Cost Model: Found an estimated cost of 3 for instruction: %v2 = insertelement <2 x i64> %vec, i64 %v1, i32 0
 ; KRYO-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret <2 x i64> %v2
 ;
 ; NEO-LABEL: 'LD1_X'
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v1 = load i64, ptr %i, align 8
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %v2 = insertelement <2 x i64> %vec, i64 %v1, i32 0
 ; NEO-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret <2 x i64> %v2
 ;
 ; AA14-LABEL: 'LD1_X':
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 1 for instruction:   %v1 = load i64, ptr %i, align 8
-; AA14-NEXT:  Cost Model: Found an estimated cost of 4 for instruction:   %v2 = insertelement <2 x i64> %vec, i64 %v1, i32 0
+; AA14-NEXT:  Cost Model: Found an estimated cost of 3 for instruction:   %v2 = insertelement <2 x i64> %vec, i64 %v1, i32 0
 ; AA14-NEXT:  Cost Model: Found an estimated cost of 0 for instruction:   ret <2 x i64> %v2
 ;
 entry:
   %v1 = load i64, ptr %i, align 8
   %v2 = insertelement <2 x i64> %vec, i64 %v1, i32 0
   ret <2 x i64> %v2
 }