[Qemu-devel] [PULL 40/55] acpi: aml: add helper for Opcode Arg2 Arg2 [Dst] AML pattern

["Michael S. Tsirkin" <mst@redhat.com>]

From: Igor Mammedov <imammedo@redhat.com>

Currently AML API doesn't compose terms in form of
following pattern:

   Opcode Arg2 Arg2 [Dst]

but ASL used in piix4/q35 DSDT ACPI tables uses that
form, so for clean conversion of it, AML API should
be able to handle an optional 'Dst' argumet used there.

Since above pattern is used by arithmetic/bit ops,
introduce helper that they could reuse.
It reduces code duplication in existing 5 aml_foo()
functions and also will prevent more duplication
when exiting functions are extended to support
optional 'Dst' argument.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Shannon Zhao <shannon.zhao@linaro.org>
---
 hw/acpi/aml-build.c | 61 ++++++++++++++++++++++++++++-------------------------
 1 file changed, 32 insertions(+), 29 deletions(-)

diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c
index 95f9af9..c661d58 100644
--- a/hw/acpi/aml-build.c
+++ b/hw/acpi/aml-build.c
@@ -436,44 +436,55 @@ Aml *aml_store(Aml *val, Aml *target)
     return var;
 }
 
-/* ACPI 1.0b: 16.2.5.4 Type 2 Opcodes Encoding: DefAnd */
-Aml *aml_and(Aml *arg1, Aml *arg2)
+/**
+ * build_opcode_2arg_dst:
+ * @op: 1-byte opcode
+ * @arg1: 1st operand
+ * @arg2: 2nd operand
+ * @dst: optional target to store to, set to NULL if it's not required
+ *
+ * An internal helper to compose AML terms that have
+ *   "Op Operand Operand Target"
+ * pattern.
+ *
+ * Returns: The newly allocated and composed according to patter Aml object.
+ */
+static Aml *
+build_opcode_2arg_dst(uint8_t op, Aml *arg1, Aml *arg2, Aml *dst)
 {
-    Aml *var = aml_opcode(0x7B /* AndOp */);
+    Aml *var = aml_opcode(op);
     aml_append(var, arg1);
     aml_append(var, arg2);
-    build_append_byte(var->buf, 0x00 /* NullNameOp */);
+    if (dst) {
+        aml_append(var, dst);
+    } else {
+        build_append_byte(var->buf, 0x00 /* NullNameOp */);
+    }
     return var;
 }
 
+/* ACPI 1.0b: 16.2.5.4 Type 2 Opcodes Encoding: DefAnd */
+Aml *aml_and(Aml *arg1, Aml *arg2)
+{
+    return build_opcode_2arg_dst(0x7B /* AndOp */, arg1, arg2, NULL);
+}
+
 /* ACPI 1.0b: 16.2.5.4 Type 2 Opcodes Encoding: DefOr */
 Aml *aml_or(Aml *arg1, Aml *arg2)
 {
-    Aml *var = aml_opcode(0x7D /* OrOp */);
-    aml_append(var, arg1);
-    aml_append(var, arg2);
-    build_append_byte(var->buf, 0x00 /* NullNameOp */);
-    return var;
+    return build_opcode_2arg_dst(0x7D /* OrOp */, arg1, arg2, NULL);
 }
 
 /* ACPI 1.0b: 16.2.5.4 Type 2 Opcodes Encoding: DefShiftLeft */
 Aml *aml_shiftleft(Aml *arg1, Aml *count)
 {
-    Aml *var = aml_opcode(0x79 /* ShiftLeftOp */);
-    aml_append(var, arg1);
-    aml_append(var, count);
-    build_append_byte(var->buf, 0x00); /* NullNameOp */
-    return var;
+    return build_opcode_2arg_dst(0x79 /* ShiftLeftOp */, arg1, count, NULL);
 }
 
 /* ACPI 1.0b: 16.2.5.4 Type 2 Opcodes Encoding: DefShiftRight */
 Aml *aml_shiftright(Aml *arg1, Aml *count)
 {
-    Aml *var = aml_opcode(0x7A /* ShiftRightOp */);
-    aml_append(var, arg1);
-    aml_append(var, count);
-    build_append_byte(var->buf, 0x00); /* NullNameOp */
-    return var;
+    return build_opcode_2arg_dst(0x7A /* ShiftRightOp */, arg1, count, NULL);
 }
 
 /* ACPI 1.0b: 16.2.5.4 Type 2 Opcodes Encoding: DefLLess */
@@ -488,11 +499,7 @@ Aml *aml_lless(Aml *arg1, Aml *arg2)
 /* ACPI 1.0b: 16.2.5.4 Type 2 Opcodes Encoding: DefAdd */
 Aml *aml_add(Aml *arg1, Aml *arg2)
 {
-    Aml *var = aml_opcode(0x72 /* AddOp */);
-    aml_append(var, arg1);
-    aml_append(var, arg2);
-    build_append_byte(var->buf, 0x00 /* NullNameOp */);
-    return var;
+    return build_opcode_2arg_dst(0x72 /* AddOp */, arg1, arg2, NULL);
 }
 
 /* ACPI 1.0b: 16.2.5.4 Type 2 Opcodes Encoding: DefIncrement */
@@ -506,11 +513,7 @@ Aml *aml_increment(Aml *arg)
 /* ACPI 1.0b: 16.2.5.4 Type 2 Opcodes Encoding: DefIndex */
 Aml *aml_index(Aml *arg1, Aml *idx)
 {
-    Aml *var = aml_opcode(0x88 /* IndexOp */);
-    aml_append(var, arg1);
-    aml_append(var, idx);
-    build_append_byte(var->buf, 0x00 /* NullNameOp */);
-    return var;
+    return build_opcode_2arg_dst(0x88 /* IndexOp */, arg1, idx, NULL);
 }
 
 /* ACPI 1.0b: 16.2.5.3 Type 1 Opcodes Encoding: DefNotify */
-- 
MST