agx: Dynamically size split instruction

This is more flexible.

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18804>

src/asahi/compiler/agx_compile.c

@@ -208,13 +208,12 @@ agx_block_add_successor(agx_block *block, agx_block *successor)
 static void
 agx_emit_split(agx_builder *b, agx_index *dests, agx_index vec, unsigned n)
 {
-   /* Setup the destinations */
+   agx_instr *I = agx_split(b, n, vec);
-   for (unsigned i = 0; i < n; ++i) {
-      dests[i] = agx_temp(b->shader, vec.size);
-   }
 
-   /* Emit the split */
+   agx_foreach_dest(I, d) {
-   agx_split_to(b, dests[0], dests[1], dests[2], dests[3], vec);
+      dests[d] = agx_temp(b->shader, vec.size);
+      I->dest[d] = dests[d];
+   }
 }
 
 static void
@@ -255,7 +254,10 @@ agx_umul_high_to(agx_builder *b, agx_index dst, agx_index P, agx_index Q)
 
    agx_index product = agx_temp(b->shader, P.size + 1);
    agx_imad_to(b, product, agx_abs(P), agx_abs(Q), agx_zero(), 0);
-   return agx_split_to(b, agx_null(), dst, agx_null(), agx_null(), product);
+
+   agx_instr *split = agx_split(b, 2, product);
+   split->dest[1] = dst;
+   return split;
 }
 
 static agx_index

src/asahi/compiler/agx_compiler.h

@@ -209,9 +209,6 @@ agx_is_equiv(agx_index left, agx_index right)
    return (left.type == right.type) && (left.value == right.value);
 }
 
-#define AGX_MAX_DESTS 4
-#define AGX_MAX_SRCS 5
-
 enum agx_icond {
    AGX_ICOND_UEQ = 0,
    AGX_ICOND_ULT = 1,

src/asahi/compiler/agx_opcodes.py

@@ -266,7 +266,7 @@ op("or", _, srcs = 2)
 op("logical_end", _, dests = 0, srcs = 0, can_eliminate = False)
 
 op("combine", _, srcs = VARIABLE)
-op("split", _, srcs = 1, dests = 4)
+op("split", _, srcs = 1, dests = VARIABLE)
 op("phi", _, srcs = VARIABLE)
 
 op("unit_test", _, dests = 0, srcs = 1, can_eliminate = False)

src/asahi/compiler/agx_print.c

@@ -121,7 +121,7 @@ agx_print_instr(agx_instr *I, FILE *fp)
 
    bool print_comma = false;
 
-   for (unsigned d = 0; d < info.nr_dests; ++d) {
+   agx_foreach_dest(I, d) {
       if (print_comma)
          fprintf(fp, ", ");
       else
@@ -130,7 +130,7 @@ agx_print_instr(agx_instr *I, FILE *fp)
       agx_print_index(I->dest[d], false, fp);
    }
 
-   for (unsigned s = 0; s < I->nr_srcs; ++s) {
+   agx_foreach_src(I, s) {
       if (print_comma)
          fprintf(fp, ", ");
       else

src/asahi/compiler/agx_register_allocate.c

@@ -333,10 +333,12 @@ agx_ra(agx_context *ctx)
          unsigned width = agx_size_align_16(agx_split_width(ins));
 
          struct agx_copy copies[4];
+         assert(ins->nr_dests <= ARRAY_SIZE(copies));
+
          unsigned n = 0;
 
          /* Move the sources */
-         for (unsigned i = 0; i < 4; ++i) {
+         agx_foreach_dest(ins, i) {
             if (agx_is_null(ins->dest[i])) continue;
 
             copies[n++] = (struct agx_copy) {