8248870: AARCH64: I2L/L2I conversions can be skipped for masked positive values

Reviewed-by: aph

Author: Boris Ulasevich

src/hotspot/cpu/aarch64/aarch64.ad

@@ -12171,6 +12171,21 @@ instruct ubfizIConvI2L(iRegLNoSp dst, iRegIorL2I src, immI lshift, immI_bitmask
   ins_pipe(ialu_reg_shift);
 %}
 
+// This pattern is automatically generated from aarch64_ad.m4
+// DO NOT EDIT ANYTHING IN THIS SECTION OF THE FILE
+
+// Can skip int2long conversions after AND with small bitmask
+instruct ubfizIConvI2LAndI(iRegLNoSp dst, iRegI src, immI_bitmask msk)
+%{
+  match(Set dst (ConvI2L (AndI src msk)));
+  ins_cost(INSN_COST);
+  format %{ "ubfiz $dst, $src, 0, exact_log2($msk + 1) " %}
+  ins_encode %{
+    __ ubfiz(as_Register($dst$$reg), as_Register($src$$reg), 0, exact_log2($msk$$constant + 1));
+  %}
+  ins_pipe(ialu_reg_shift);
+%}
+
 
 // Rotations 
 // This pattern is automatically generated from aarch64_ad.m4

src/hotspot/cpu/aarch64/aarch64_ad.m4

@@ -278,6 +278,21 @@ instruct ubfizIConvI2L(iRegLNoSp dst, iRegIorL2I src, immI lshift, immI_bitmask
   ins_pipe(ialu_reg_shift);
 %}
 
+// This pattern is automatically generated from aarch64_ad.m4
+// DO NOT EDIT ANYTHING IN THIS SECTION OF THE FILE
+
+// Can skip int2long conversions after AND with small bitmask
+instruct ubfizIConvI2LAndI(iRegLNoSp dst, iRegI src, immI_bitmask msk)
+%{
+  match(Set dst (ConvI2L (AndI src msk)));
+  ins_cost(INSN_COST);
+  format %{ "ubfiz $dst, $src, 0, exact_log2($msk + 1) " %}
+  ins_encode %{
+    __ ubfiz(as_Register($dst$$reg), as_Register($src$$reg), 0, exact_log2($msk$$constant + 1));
+  %}
+  ins_pipe(ialu_reg_shift);
+%}
+
 
 // Rotations dnl
 define(`EXTRACT_INSN',`

test/micro/org/openjdk/bench/vm/compiler/SkipIntToLongCast.java

@@ -47,6 +47,7 @@ public class SkipIntToLongCast {
     private static final long ARRAYSIZE_L = 40L;
 
     public int[] intValues;
+    public int intValue;
 
     @Setup
     public void setup() {
@@ -76,4 +77,13 @@ public int skipCastTestLeft() {
         }
         return 0;
     }
+
+    @Benchmark
+    public long skipMaskedSmallPositiveCast() {
+        int value = intValue;
+        return (long)(value & 0x1)    ^ (long)(value & 0x3)    ^ (long)(value & 0x7)    ^ (long)(value & 0xF)   ^
+               (long)(value & 0x1F)   ^ (long)(value & 0x3F)   ^ (long)(value & 0x7F)   ^ (long)(value & 0xFF)  ^
+               (long)(value & 0x1FF)  ^ (long)(value & 0x3FF)  ^ (long)(value & 0x7FF)  ^ (long)(value & 0xFFF) ^
+               (long)(value & 0x1FFF) ^ (long)(value & 0x3FFF) ^ (long)(value & 0x7FFF) ^ (long)(value & 0xFFFF);
+    }
 }