[IRTranslator] Add G_SUB opcode.

This commit adds a generic SUB opcode to global-isel.

llvm-svn: 276308

llvm/include/llvm/Target/GenericOpcodes.td

@@ -23,6 +23,14 @@ def G_ADD : Instruction {
   let isCommutable = 1;
 }
 
+// Generic subtraction.
+def G_SUB : Instruction {
+  let OutOperandList = (outs unknown:$dst);
+  let InOperandList = (ins unknown:$src1, unknown:$src2);
+  let hasSideEffects = 0;
+  let isCommutable = 0;
+}
+
 // Generic bitwise and.
 def G_AND : Instruction {
   let OutOperandList = (outs unknown:$dst);

llvm/include/llvm/Target/TargetOpcodes.def

@@ -159,6 +159,9 @@ HANDLE_TARGET_OPCODE(PATCHABLE_RET)
 HANDLE_TARGET_OPCODE(G_ADD)
 HANDLE_TARGET_OPCODE_MARKER(PRE_ISEL_GENERIC_OPCODE_START, G_ADD)
 
+/// Generic SUB instruction. This is an integer sub.
+HANDLE_TARGET_OPCODE(G_SUB)
+
 /// Generic Bitwise-AND instruction.
 HANDLE_TARGET_OPCODE(G_AND)
 

llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp

@@ -105,6 +105,8 @@ bool IRTranslator::translate(const Instruction &Inst) {
   // Arithmetic operations.
   case Instruction::Add:
     return translateBinaryOp(TargetOpcode::G_ADD, Inst);
+  case Instruction::Sub:
+    return translateBinaryOp(TargetOpcode::G_SUB, Inst);
   // Bitwise operations.
   case Instruction::And:
     return translateBinaryOp(TargetOpcode::G_AND, Inst);

llvm/test/CodeGen/AArch64/GlobalISel/arm64-irtranslator.ll

@@ -84,3 +84,26 @@ define i32 @andi32(i32 %arg1, i32 %arg2) {
   %res = and i32 %arg1, %arg2
   ret i32 %res
 }
+
+; Tests for sub.
+; CHECK: name: subi64
+; CHECK: [[ARG1:%[0-9]+]](64) = COPY %x0
+; CHECK-NEXT: [[ARG2:%[0-9]+]](64) = COPY %x1
+; CHECK-NEXT: [[RES:%[0-9]+]](64) = G_SUB s64 [[ARG1]], [[ARG2]]
+; CHECK-NEXT: %x0 = COPY [[RES]]
+; CHECK-NEXT: RET_ReallyLR implicit %x0
+define i64 @subi64(i64 %arg1, i64 %arg2) {
+  %res = sub i64 %arg1, %arg2
+  ret i64 %res
+}
+
+; CHECK: name: subi32
+; CHECK: [[ARG1:%[0-9]+]](32) = COPY %w0
+; CHECK-NEXT: [[ARG2:%[0-9]+]](32) = COPY %w1
+; CHECK-NEXT: [[RES:%[0-9]+]](32) = G_SUB s32 [[ARG1]], [[ARG2]]
+; CHECK-NEXT: %w0 = COPY [[RES]]
+; CHECK-NEXT: RET_ReallyLR implicit %w0
+define i32 @subi32(i32 %arg1, i32 %arg2) {
+  %res = sub i32 %arg1, %arg2
+  ret i32 %res
+}