agx: Add stack adjust opcode

Signed-off-by: Mary Guillemard <mary@mary.zone>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/26056>

src/asahi/compiler/agx_compiler.h

@@ -290,6 +290,7 @@ typedef struct {
       uint32_t bfi_mask;
       uint16_t pixel_offset;
       uint16_t zs;
+      int16_t stack_size;
       enum agx_sr sr;
       enum agx_round round;
       enum agx_atomic_opc atomic_opc;

src/asahi/compiler/agx_opcodes.py

@@ -80,6 +80,7 @@ MASK = immediate("mask")
 BFI_MASK = immediate("bfi_mask")
 LOD_MODE = immediate("lod_mode", "enum agx_lod_mode")
 PIXEL_OFFSET = immediate("pixel_offset")
+STACK_SIZE = immediate("stack_size", 'int16_t')
 
 DIM = enum("dim", {
     0: '1d',
@@ -427,6 +428,11 @@ op("doorbell", (0x60020 | 0x28 << 32, (1 << 48) - 1, 6, _), dests = 0,
 op("stack_unmap", (0x00075, (1 << 24) - 1, 8, _), dests = 1, srcs = 0, can_eliminate = False, can_reorder = False, imms = [IMM])
 op("stack_map",   (0x10075, (1 << 24) - 1, 8, _), dests = 0, srcs = 1, can_eliminate = False, can_reorder = False, imms = [IMM])
 
+op("stack_adjust",
+      encoding_32 = (0x10100b5, (1 << 26) - 1, 8, _),
+      dests = 0, srcs = 0, can_eliminate = False, can_reorder = False,
+      imms = [STACK_SIZE], schedule_class = "store")
+
 # source is offset
 op("stack_load",
       encoding_32 = (0x35, (1 << 20) - 1, 6, 8),

src/asahi/compiler/agx_pack.c

@@ -1039,6 +1039,25 @@ agx_pack_instr(struct util_dynarray *emission, struct util_dynarray *fixups,
       memcpy(util_dynarray_grow_bytes(emission, 1, size), &raw, size);
       break;
    }
+   case AGX_OPCODE_STACK_ADJUST: {
+      struct agx_opcode_info info = agx_opcodes_info[I->op];
+
+      unsigned i0 = 0; // XXX
+      unsigned i1 = 1; // XXX
+      unsigned i2 = 2; // XXX
+      unsigned i3 = 0; // XXX
+      unsigned i4 = 0; // XXX
+
+      uint64_t raw =
+         info.encoding.exact | ((uint64_t)i0 << 8) | ((uint64_t)i1 << 26) |
+         ((uint64_t)i2 << 36) | ((uint64_t)i3 << 44) | ((uint64_t)i4 << 50) |
+         ((I->stack_size & 0xF) << 20) |
+         ((uint64_t)((I->stack_size >> 4) & 0xF) << 32) | (1UL << 47) | // XXX
+         ((uint64_t)(I->stack_size >> 8) << 56);
+
+      memcpy(util_dynarray_grow_bytes(emission, 1, 8), &raw, 8);
+      break;
+   }
 
    default:
       agx_pack_alu(emission, I);