nv50: prepare for having multiple functions

At some point we'll want to support real subroutines instead of
just inlining them into the main shader.

Since recursive calls are forbidden, we can just save all used
registers to a fixed local memory region and restore them on a
return, no need for a stack pointer.

1 files changed, 17 insertions, 6 deletions

diff --git a/src/gallium/drivers/nv50/nv50_pc_regalloc.c b/src/gallium/drivers/nv50/nv50_pc_regalloc.c
index d401706b5b..2998343db5 100644
--- a/src/gallium/drivers/nv50/nv50_pc_regalloc.c
+++ b/src/gallium/drivers/nv50/nv50_pc_regalloc.c
@@ -874,8 +874,8 @@ pass_linear_scan(struct nv_pc_pass *ctx, int iter)
    return 0;
 }
 
-int
-nv_pc_exec_pass1(struct nv_pc *pc)
+static int
+nv_pc_pass1(struct nv_pc *pc, struct nv_basic_block *root)
 {
    struct nv_pc_pass *ctx;
    int i, ret;
@@ -890,12 +890,12 @@ nv_pc_exec_pass1(struct nv_pc *pc)
    ctx->insns = CALLOC(NV_PC_MAX_INSTRUCTIONS, sizeof(struct nv_instruction *));
 
    pc->pass_seq++;
-   ret = pass_generate_phi_movs(ctx, pc->root);
+   ret = pass_generate_phi_movs(ctx, root);
    assert(!ret);
 
    for (i = 0; i < pc->loop_nesting_bound; ++i) {
       pc->pass_seq++;
-      ret = pass_build_live_sets(ctx, pc->root);
+      ret = pass_build_live_sets(ctx, root);
       assert(!ret && "live sets");
       if (ret) {
          NOUVEAU_ERR("failed to build live sets (iteration %d)\n", i);
@@ -904,10 +904,10 @@ nv_pc_exec_pass1(struct nv_pc *pc)
    }
 
    pc->pass_seq++;
-   nv_pc_pass_in_order(pc->root, pass_order_instructions, ctx);
+   nv_pc_pass_in_order(root, pass_order_instructions, ctx);
 
    pc->pass_seq++;
-   ret = pass_build_intervals(ctx, pc->root);
+   ret = pass_build_intervals(ctx, root);
    assert(!ret && "build intervals");
    if (ret) {
       NOUVEAU_ERR("failed to build live intervals\n");
@@ -944,3 +944,14 @@ out:
    FREE(ctx);
    return ret;
 }
+
+int
+nv_pc_exec_pass1(struct nv_pc *pc)
+{
+   int i, ret;
+
+   for (i = 0; i < pc->num_subroutines + 1; ++i)
+      if (pc->root[i] && (ret = nv_pc_pass1(pc, pc->root[i])))
+         return ret;
+   return 0;
+}