glsl: remove glsl ir optimisation loop from linker

We no longer need to call this here and can depend on the glsl_to_nir
pass to call it and clean up anything it cannot handle. Everything
else can now depend on the nir optimisation passes.

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22846>

src/compiler/glsl/glsl_to_nir.cpp

@@ -210,6 +210,12 @@ glsl_to_nir(const struct gl_constants *consts,
 
    MESA_TRACE_FUNC();
 
+   /* NIR cannot handle instructions after a break so we use the GLSL IR do
+    * lower jumps pass to clean those up for now.
+    */
+   do_lower_jumps(sh->ir, true, true, gl_options->EmitNoMainReturn,
+                  gl_options->EmitNoCont);
+
    /* glsl_to_nir can only handle converting certain function paramaters
     * to NIR. If we find something we can't handle then we get the GLSL IR
     * opts to remove it before we continue on.

src/compiler/glsl/linker.cpp

@@ -3667,10 +3667,6 @@ link_shaders(struct gl_context *ctx, struct gl_shader_program *prog)
    if (!interstage_cross_validate_uniform_blocks(prog, true))
       goto done;
 
-   /* Do common optimization before assigning storage for attributes,
-    * uniforms, and varyings.  Later optimization could possibly make
-    * some of that unused.
-    */
    for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) {
       if (prog->_LinkedShaders[i] == NULL)
          continue;
@@ -3703,11 +3699,6 @@ link_shaders(struct gl_context *ctx, struct gl_shader_program *prog)
             goto done;
          }
       }
-
-      /* Run it just once, since NIR will do the real optimizaiton. */
-      do_common_optimization(prog->_LinkedShaders[i]->ir, true,
-                             &consts->ShaderCompilerOptions[i],
-                             consts->NativeIntegers);
    }
 
    /* Check and validate stream emissions in geometry shaders */

src/compiler/glsl/tests/test_gl_lower_mediump.cpp

@@ -444,7 +444,7 @@ TEST_F(gl_nir_lower_mediump_test, func_args_in_mediump)
          }
     )"));
 
-   EXPECT_PRED_FORMAT2(glsl_ir_contains, fs_ir, "expression float16_t * (expression float16_t f2fmp (var_ref a) ) (expression float16_t f2fmp (var_ref b) ) )");
+   EXPECT_PRED_FORMAT2(glsl_ir_contains, fs_ir, "expression float f162f (expression float16_t * (expression float16_t f2fmp (var_ref x) ) (expression float16_t f2fmp (var_ref y) ) )");
 
    /* NIR optimization will notice that we downconvert the highp to mediump just
     * to multiply and cast back up, and just multiply in highp instead.

src/gallium/drivers/llvmpipe/ci/traces-llvmpipe.yml

@@ -132,7 +132,7 @@ traces:
       checksum: db43c733f3f3d5253e263838e58d9111
   paraview/pv-waveletvolume-v2.trace:
     gl-vmware-llvmpipe:
-      checksum: f4af4067b37c00861fa5911e4c0a6629
+      checksum: 7e0fc4f2f8c635e571793ed8fa705f85
   pathfinder/canvas_moire-v2.trace:
     gl-vmware-llvmpipe:
       checksum: 25ba8f18274126670311bd3ffe058f74

src/gallium/drivers/virgl/ci/traces-virgl.yml

@@ -81,7 +81,7 @@ traces:
       label: [crash]
   paraview/pv-waveletvolume-v2.trace:
     gl-virgl:
-      checksum: f4af4067b37c00861fa5911e4c0a6629
+      checksum: 7e0fc4f2f8c635e571793ed8fa705f85
   supertuxkart/supertuxkart-mansion-egl-gles-v2.trace:
     gl-virgl:
       checksum: 4ac8b872bfa701632d76801a3f77c5db