intel/compiler: Use linear allocator for ACP trees in copy-prop

Replace usage of variable length array.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Antonio Ospite <None>
Reviewed-by: Kenneth Graunke <None>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/32916>

src/intel/compiler/brw_opt_copy_propagation.cpp

@@ -143,6 +143,8 @@ private:
 };
 
 struct acp {
+   DECLARE_LINEAR_ALLOC_CXX_OPERATORS(acp);
+
    struct rb_tree by_dst;
    struct rb_tree by_src;
 
@@ -1420,7 +1422,7 @@ brw_opt_copy_propagation(fs_visitor &s)
    bool progress = false;
    void *copy_prop_ctx = ralloc_context(NULL);
    linear_ctx *lin_ctx = linear_context(copy_prop_ctx);
-   struct acp out_acp[s.cfg->num_blocks];
+   struct acp *out_acp = new (lin_ctx) acp[s.cfg->num_blocks];
 
    const fs_live_variables &live = s.live_analysis.require();
 

src/intel/compiler/elk/elk_fs_copy_propagation.cpp

@@ -143,6 +143,8 @@ private:
 };
 
 struct acp {
+   DECLARE_LINEAR_ALLOC_CXX_OPERATORS(acp);
+
    struct rb_tree by_dst;
    struct rb_tree by_src;
 
@@ -1350,7 +1352,7 @@ elk_fs_visitor::opt_copy_propagation()
    bool progress = false;
    void *copy_prop_ctx = ralloc_context(NULL);
    linear_ctx *lin_ctx = linear_context(copy_prop_ctx);
-   struct acp out_acp[cfg->num_blocks];
+   struct acp *out_acp = new (lin_ctx) acp[cfg->num_blocks];
 
    const fs_live_variables &live = live_analysis.require();