linker: shrink default palette load from inline stores to loop

The reset-time "no user palette" path was emitting 32 unrolled `LDA #imm / STA $2007` pairs (~170 bytes) to write the built-in palette. Replace it with the same indirect-loop loader the user-palette path already uses (runtime::gen_initial_palette_load), with the 32-byte default palette spliced into PRG under a `__default_palette` data block. Net saving is ~120 bytes — ~20 bytes of code + 32 bytes of data vs ~170 bytes of unrolled stores. Delete `Linker::gen_palette_load` (dead after the refactor) and its unit test. Replace with two tests covering the observable behaviour: the default palette bytes appear in PRG when no user palette is declared, and the `__default_palette` label is suppressed when the user does declare a palette. Audio goldens flip again for audio_demo, noise_triangle_sfx, and sfx_pitch_envelope. These are the three audio examples that don't declare their own palette — shrinking the default-palette load shifts their audio tick's absolute address by ~120 bytes, which changes branch page-crossing timing and therefore the exact APU register write sample offsets. Same class of drift as the mul/divide gating commit. https://claude.ai/code/session_016kM6P7PukktBDqTZexrrAN
2026-07-08 08:55:38 +00:00 · 2026-04-16 13:07:45 +00:00 · 2026-04-16 13:07:45 +00:00 · 37974611ae
commit 37974611ae
parent 033d399565
32 changed files with 74 additions and 46 deletions
--- a/examples/arrays_and_functions.nes
+++ b/examples/arrays_and_functions.nes
--- a/examples/audio_demo.nes
+++ b/examples/audio_demo.nes
--- a/examples/bitwise_ops.nes
+++ b/examples/bitwise_ops.nes
--- a/examples/bouncing_ball.nes
+++ b/examples/bouncing_ball.nes
--- a/examples/coin_cavern.nes
+++ b/examples/coin_cavern.nes
--- a/examples/comparisons.nes
+++ b/examples/comparisons.nes
--- a/examples/function_chain.nes
+++ b/examples/function_chain.nes
--- a/examples/hello_sprite.nes
+++ b/examples/hello_sprite.nes
--- a/examples/inline_asm_demo.nes
+++ b/examples/inline_asm_demo.nes
--- a/examples/logic_ops.nes
+++ b/examples/logic_ops.nes
--- a/examples/loop_break_continue.nes
+++ b/examples/loop_break_continue.nes
--- a/examples/match_demo.nes
+++ b/examples/match_demo.nes
--- a/examples/metasprite_demo.nes
+++ b/examples/metasprite_demo.nes
--- a/examples/mmc1_banked.nes
+++ b/examples/mmc1_banked.nes
--- a/examples/mmc3_per_state_split.nes
+++ b/examples/mmc3_per_state_split.nes
--- a/examples/nested_structs.nes
+++ b/examples/nested_structs.nes
--- a/examples/noise_triangle_sfx.nes
+++ b/examples/noise_triangle_sfx.nes
--- a/examples/scanline_split.nes
+++ b/examples/scanline_split.nes
--- a/examples/sfx_pitch_envelope.nes
+++ b/examples/sfx_pitch_envelope.nes
--- a/examples/sprite_flicker_demo.nes
+++ b/examples/sprite_flicker_demo.nes
--- a/examples/sprites_and_palettes.nes
+++ b/examples/sprites_and_palettes.nes
--- a/examples/state_machine.nes
+++ b/examples/state_machine.nes
--- a/examples/structs_enums_for.nes
+++ b/examples/structs_enums_for.nes
--- a/examples/two_player.nes
+++ b/examples/two_player.nes
--- a/examples/uxrom_banked.nes
+++ b/examples/uxrom_banked.nes
--- a/examples/uxrom_banked_to_banked.nes
+++ b/examples/uxrom_banked_to_banked.nes
--- a/examples/uxrom_user_banked.nes
+++ b/examples/uxrom_user_banked.nes