radv/ac: handle gs inputs

This handles geometry shader inputs written by the vertex (es) shader
to the esgs ring.

Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --git a/src/amd/common/ac_nir_to_llvm.c b/src/amd/common/ac_nir_to_llvm.c
index 0e5fb1736be99b5c15c41aa5102189b2e236ae79..593128867cd775683917f20504e4a8c1b081ede9 100644 (file)
--- a/src/amd/common/ac_nir_to_llvm.c
+++ b/src/amd/common/ac_nir_to_llvm.c
@@ -173,6 +173,21 @@ static unsigned radeon_llvm_reg_index_soa(unsigned index, unsigned chan)
        return (index * 4) + chan;
 }
 
+static unsigned shader_io_get_unique_index(gl_varying_slot slot)
+{
+       if (slot == VARYING_SLOT_POS)
+               return 0;
+       if (slot == VARYING_SLOT_PSIZ)
+               return 1;
+       if (slot == VARYING_SLOT_CLIP_DIST0)
+               return 2;
+       if (slot == VARYING_SLOT_CLIP_DIST1)
+               return 3;
+       if (slot >= VARYING_SLOT_VAR0 && slot <= VARYING_SLOT_VAR31)
+               return 4 + (slot - VARYING_SLOT_VAR0);
+       unreachable("illegal slot in get unique index\n");
+}
+
 static unsigned llvm_get_type_size(LLVMTypeRef type)
 {
        LLVMTypeKind kind = LLVMGetTypeKind(type);
@@ -2153,6 +2168,44 @@ radv_get_deref_offset(struct nir_to_llvm_context *ctx, nir_deref *tail,
        *indir_out = offset;
 }
 
+static LLVMValueRef
+load_gs_input(struct nir_to_llvm_context *ctx,
+             nir_intrinsic_instr *instr)
+{
+       LLVMValueRef indir_index, vtx_offset;
+       unsigned const_index;
+       LLVMValueRef args[9];
+       unsigned param, vtx_offset_param;
+       LLVMValueRef value[4], result;
+       unsigned vertex_index;
+       radv_get_deref_offset(ctx, &instr->variables[0]->deref,
+                             false, &vertex_index,
+                             &const_index, &indir_index);
+       vtx_offset_param = vertex_index;
+       assert(vtx_offset_param < 6);
+       vtx_offset = LLVMBuildMul(ctx->builder, ctx->gs_vtx_offset[vtx_offset_param],
+                                 LLVMConstInt(ctx->i32, 4, false), "");
+
+       for (unsigned i = 0; i < instr->num_components; i++) {
+               param = shader_io_get_unique_index(instr->variables[0]->var->data.location);
+               args[0] = ctx->esgs_ring;
+               args[1] = vtx_offset;
+               args[2] = LLVMConstInt(ctx->i32, (param * 4 + i) * 256, false);
+               args[3] = ctx->i32zero;
+               args[4] = ctx->i32one; /* OFFEN */
+               args[5] = ctx->i32zero; /* IDXEN */
+               args[6] = ctx->i32one; /* GLC */
+               args[7] = ctx->i32zero; /* SLC */
+               args[8] = ctx->i32zero; /* TFE */
+
+               value[i] = ac_emit_llvm_intrinsic(&ctx->ac, "llvm.SI.buffer.load.dword.i32.i32",
+                                           ctx->i32, args, 9, AC_FUNC_ATTR_READONLY);
+       }
+       result = ac_build_gather_values(&ctx->ac, value, instr->num_components);
+
+       return result;
+}
+
 static LLVMValueRef visit_load_var(struct nir_to_llvm_context *ctx,
                                   nir_intrinsic_instr *instr)
 {
@@ -2163,6 +2216,9 @@ static LLVMValueRef visit_load_var(struct nir_to_llvm_context *ctx,
        unsigned const_index;
        switch (instr->variables[0]->var->data.mode) {
        case nir_var_shader_in:
+               if (ctx->stage == MESA_SHADER_GEOMETRY) {
+                       return load_gs_input(ctx, instr);
+               }
                radv_get_deref_offset(ctx, &instr->variables[0]->deref,
                                      ctx->stage == MESA_SHADER_VERTEX, NULL,
                                      &const_index, &indir_index);