8075136: Unnecessary sign extension for byte array access

Summary: Added C2 matching rules to remove unnecessary sign extension for byte array access.
Reviewed-by: roland, kvn, aph, adinn

src/cpu/x86/vm/x86_64.ad

@@ -3740,6 +3740,23 @@ operand indIndexScaleOffset(any_RegP reg, immL32 off, rRegL lreg, immI2 scale)
   %}
 %}
 
+// Indirect Memory Plus Positive Index Register Plus Offset Operand
+operand indPosIndexOffset(any_RegP reg, immL32 off, rRegI idx)
+%{
+  constraint(ALLOC_IN_RC(ptr_reg));
+  predicate(n->in(2)->in(3)->as_Type()->type()->is_long()->_lo >= 0);
+  match(AddP (AddP reg (ConvI2L idx)) off);
+
+  op_cost(10);
+  format %{"[$reg + $off + $idx]" %}
+  interface(MEMORY_INTER) %{
+    base($reg);
+    index($idx);
+    scale(0x0);
+    disp($off);
+  %}
+%}
+
 // Indirect Memory Times Scale Plus Positive Index Register Plus Offset Operand
 operand indPosIndexScaleOffset(any_RegP reg, immL32 off, rRegI idx, immI2 scale)
 %{
@@ -3891,6 +3908,23 @@ operand indIndexScaleOffsetNarrow(rRegN reg, immL32 off, rRegL lreg, immI2 scale
   %}
 %}
 
+// Indirect Memory Times Plus Positive Index Register Plus Offset Operand
+operand indPosIndexOffsetNarrow(rRegN reg, immL32 off, rRegI idx)
+%{
+  constraint(ALLOC_IN_RC(ptr_reg));
+  predicate(Universe::narrow_oop_shift() == 0 && n->in(2)->in(3)->as_Type()->type()->is_long()->_lo >= 0);
+  match(AddP (AddP (DecodeN reg) (ConvI2L idx)) off);
+
+  op_cost(10);
+  format %{"[$reg + $off + $idx]" %}
+  interface(MEMORY_INTER) %{
+    base($reg);
+    index($idx);
+    scale(0x0);
+    disp($off);
+  %}
+%}
+
 // Indirect Memory Times Scale Plus Positive Index Register Plus Offset Operand
 operand indPosIndexScaleOffsetNarrow(rRegN reg, immL32 off, rRegI idx, immI2 scale)
 %{
@@ -4082,11 +4116,11 @@ operand cmpOpUCF2() %{
 // case of this is memory operands.
 
 opclass memory(indirect, indOffset8, indOffset32, indIndexOffset, indIndex,
-               indIndexScale, indIndexScaleOffset, indPosIndexScaleOffset,
+               indIndexScale, indIndexScaleOffset, indPosIndexOffset, indPosIndexScaleOffset,
                indCompressedOopOffset,
                indirectNarrow, indOffset8Narrow, indOffset32Narrow,
                indIndexOffsetNarrow, indIndexNarrow, indIndexScaleNarrow,
-               indIndexScaleOffsetNarrow, indPosIndexScaleOffsetNarrow);
+               indIndexScaleOffsetNarrow, indPosIndexOffsetNarrow, indPosIndexScaleOffsetNarrow);
 
 //----------PIPELINE-----------------------------------------------------------
 // Rules which define the behavior of the target architectures pipeline.
@@ -5120,6 +5154,17 @@ instruct leaPIdxScaleOff(rRegP dst, indIndexScaleOffset mem)
   ins_pipe(ialu_reg_reg_fat);
 %}
 
+instruct leaPPosIdxOff(rRegP dst, indPosIndexOffset mem)
+%{
+  match(Set dst mem);
+
+  ins_cost(110);
+  format %{ "leaq    $dst, $mem\t# ptr posidxoff" %}
+  opcode(0x8D);
+  ins_encode(REX_reg_mem_wide(dst, mem), OpcP, reg_mem(dst, mem));
+  ins_pipe(ialu_reg_reg_fat);
+%}
+
 instruct leaPPosIdxScaleOff(rRegP dst, indPosIndexScaleOffset mem)
 %{
   match(Set dst mem);
@@ -5204,6 +5249,18 @@ instruct leaPIdxScaleOffNarrow(rRegP dst, indIndexScaleOffsetNarrow mem)
   ins_pipe(ialu_reg_reg_fat);
 %}
 
+instruct leaPPosIdxOffNarrow(rRegP dst, indPosIndexOffsetNarrow mem)
+%{
+  predicate(Universe::narrow_oop_shift() == 0);
+  match(Set dst mem);
+
+  ins_cost(110);
+  format %{ "leaq    $dst, $mem\t# ptr posidxoffnarrow" %}
+  opcode(0x8D);
+  ins_encode(REX_reg_mem_wide(dst, mem), OpcP, reg_mem(dst, mem));
+  ins_pipe(ialu_reg_reg_fat);
+%}
+
 instruct leaPPosIdxScaleOffNarrow(rRegP dst, indPosIndexScaleOffsetNarrow mem)
 %{
   predicate(Universe::narrow_oop_shift() == 0);