aco/gfx11: export mrtz in discard early exit for non-color shaders

If a shader doesn't export any color targets and instead only exports
mrtz, the discard early exit block should match.

Fixes artifacts on Lara in Rise of the Tomb Raider benchmark and hair in
The Witcher 3 (classic).

https://reviews.llvm.org/D128185

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Fixes: bc8da20dda6 ("aco: export MRT0 instead of NULL on GFX11")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20345>
(cherry picked from commit 192486b7aa5ef3b24516e16b0e219fad7032fb7c)

diff --git a/.pick_status.json b/.pick_status.json
index 9d0b994..a7bca82 100644 (file)
--- a/.pick_status.json
+++ b/.pick_status.json
@@ -2380,7 +2380,7 @@
         "description": "aco/gfx11: export mrtz in discard early exit for non-color shaders",
         "nominated": true,
         "nomination_type": 1,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": "bc8da20dda6b078aea800767f3b7983929e8bf23"
     },

diff --git a/src/amd/compiler/aco_instruction_selection.cpp b/src/amd/compiler/aco_instruction_selection.cpp
index 2d11efe..7472b45 100644 (file)
--- a/src/amd/compiler/aco_instruction_selection.cpp
+++ b/src/amd/compiler/aco_instruction_selection.cpp
@@ -11208,6 +11208,8 @@ export_mrt(isel_context* ctx, const struct aco_export_mrt* mrt)
 
    bld.exp(aco_opcode::exp, mrt->out[0], mrt->out[1], mrt->out[2], mrt->out[3],
            mrt->enabled_channels, mrt->target, mrt->compr);
+
+   ctx->program->has_color_exports = true;
 }
 
 static bool
@@ -11401,6 +11403,8 @@ create_fs_null_export(isel_context* ctx)
    unsigned dest = ctx->options->gfx_level >= GFX11 ? V_008DFC_SQ_EXP_MRT : V_008DFC_SQ_EXP_NULL;
    bld.exp(aco_opcode::exp, Operand(v1), Operand(v1), Operand(v1), Operand(v1),
            /* enabled_mask */ 0, dest, /* compr */ false, /* done */ true, /* vm */ true);
+
+   ctx->program->has_color_exports = true;
 }
 
 static void
@@ -11476,6 +11480,8 @@ create_fs_dual_src_export_gfx11(isel_context* ctx, const struct aco_export_mrt*
    exp->definitions[4] = bld.def(bld.lm, vcc);
    exp->definitions[5] = bld.def(s1, scc);
    ctx->block->instructions.emplace_back(std::move(exp));
+
+   ctx->program->has_color_exports = true;
 }
 
 static void

diff --git a/src/amd/compiler/aco_ir.h b/src/amd/compiler/aco_ir.h
index fad6272..c2b6457 100644 (file)
--- a/src/amd/compiler/aco_ir.h
+++ b/src/amd/compiler/aco_ir.h
@@ -2170,6 +2170,7 @@ public:
    Stage stage;
    bool needs_exact = false; /* there exists an instruction with disable_wqm = true */
    bool needs_wqm = false;   /* there exists a p_wqm instruction */
+   bool has_color_exports = false;
 
    std::vector<uint8_t> constant_data;
    Temp private_segment_buffer;

diff --git a/src/amd/compiler/aco_lower_to_hw_instr.cpp b/src/amd/compiler/aco_lower_to_hw_instr.cpp
index 5fb097a..f5c4c4a 100644 (file)
--- a/src/amd/compiler/aco_lower_to_hw_instr.cpp
+++ b/src/amd/compiler/aco_lower_to_hw_instr.cpp
@@ -2129,9 +2129,12 @@ lower_to_hw_instr(Program* program)
                   block = &program->blocks[block_idx];
 
                   bld.reset(discard_block);
+                  unsigned target = V_008DFC_SQ_EXP_NULL;
+                  if (program->gfx_level >= GFX11)
+                     target =
+                        program->has_color_exports ? V_008DFC_SQ_EXP_MRT : V_008DFC_SQ_EXP_MRTZ;
                   bld.exp(aco_opcode::exp, Operand(v1), Operand(v1), Operand(v1), Operand(v1), 0,
-                          program->gfx_level >= GFX11 ? V_008DFC_SQ_EXP_MRT : V_008DFC_SQ_EXP_NULL,
-                          false, true, true);
+                          target, false, true, true);
                   if (should_dealloc_vgprs)
                      bld.sopp(aco_opcode::s_sendmsg, -1, sendmsg_dealloc_vgprs);
                   bld.sopp(aco_opcode::s_endpgm);