Cycles: Kernel address space changes for MSL

This is the first of a sequence of changes to support compiling Cycles kernels as MSL (Metal Shading Language) in preparation for a Metal GPU device implementation.

MSL requires that all pointer types be declared with explicit address space attributes (device, thread, etc...). There is already precedent for this with Cycles' address space macros (ccl_global, ccl_private, etc...), therefore the first step of MSL-enablement is to apply these consistently. Line-for-line this represents the largest change required to enable MSL. Applying this change first will simplify future patches as well as offering the emergent benefit of enhanced descriptiveness.

The vast majority of deltas in this patch fall into one of two cases:

- Ensuring ccl_private is specified for thread-local pointer types
- Ensuring ccl_global is specified for device-wide pointer types

Additionally, the ccl_addr_space qualifier can be removed. Prior to Cycles X, ccl_addr_space was used as a context-dependent address space qualifier, but now it is either redundant (e.g. in struct typedefs), or can be replaced by ccl_global in the case of pointer types. Associated function variants (e.g. lcg_step_float_addrspace) are also redundant.

In cases where address space qualifiers are chained with "const", this patch places the address space qualifier first. The rationale for this is that the choice of address space is likely to have the greater impact on runtime performance and overall architecture.

The final part of this patch is the addition of a metal/compat.h header. This is partially complete and will be extended in future patches, paving the way for the full Metal implementation.

Ref T92212

Reviewed By: brecht

Maniphest Tasks: T92212

Differential Revision: https://developer.blender.org/D12864

1 files changed, 58 insertions, 49 deletions

diff --git a/intern/cycles/kernel/closure/bsdf_microfacet_multi.h b/intern/cycles/kernel/closure/bsdf_microfacet_multi.h
index 68d5071dbce..6ee1139ddbb 100644
--- a/intern/cycles/kernel/closure/bsdf_microfacet_multi.h
+++ b/intern/cycles/kernel/closure/bsdf_microfacet_multi.h
@@ -105,7 +105,7 @@ ccl_device_forceinline float3 mf_sample_vndf(const float3 wi,
 
 /* Phase function for reflective materials. */
 ccl_device_forceinline float3 mf_sample_phase_glossy(const float3 wi,
-                                                     float3 *weight,
+                                                     ccl_private float3 *weight,
                                                      const float3 wm)
 {
   return -wi + 2.0f * wm * dot(wi, wm);
@@ -140,8 +140,11 @@ ccl_device_forceinline float3 mf_eval_phase_glossy(const float3 w,
 
 /* Phase function for dielectric transmissive materials, including both reflection and refraction
  * according to the dielectric fresnel term. */
-ccl_device_forceinline float3 mf_sample_phase_glass(
-    const float3 wi, const float eta, const float3 wm, const float randV, bool *outside)
+ccl_device_forceinline float3 mf_sample_phase_glass(const float3 wi,
+                                                    const float eta,
+                                                    const float3 wm,
+                                                    const float randV,
+                                                    ccl_private bool *outside)
 {
   float cosI = dot(wi, wm);
   float f = fresnel_dielectric_cos(cosI, eta);
@@ -234,8 +237,12 @@ ccl_device_forceinline float mf_G1(const float3 w, const float C1, const float l
 
 /* Sampling from the visible height distribution (based on page 17 of the supplemental
  * implementation). */
-ccl_device_forceinline bool mf_sample_height(
-    const float3 w, float *h, float *C1, float *G1, float *lambda, const float U)
+ccl_device_forceinline bool mf_sample_height(const float3 w,
+                                             ccl_private float *h,
+                                             ccl_private float *C1,
+                                             ccl_private float *G1,
+                                             ccl_private float *lambda,
+                                             const float U)
 {
   if (w.z > 0.9999f)
     return false;
@@ -364,9 +371,9 @@ ccl_device_forceinline float mf_glass_pdf(const float3 wi,
 #define MF_MULTI_GLOSSY
 #include "kernel/closure/bsdf_microfacet_multi_impl.h"
 
-ccl_device void bsdf_microfacet_multi_ggx_blur(ShaderClosure *sc, float roughness)
+ccl_device void bsdf_microfacet_multi_ggx_blur(ccl_private ShaderClosure *sc, float roughness)
 {
-  MicrofacetBsdf *bsdf = (MicrofacetBsdf *)sc;
+  ccl_private MicrofacetBsdf *bsdf = (ccl_private MicrofacetBsdf *)sc;
 
   bsdf->alpha_x = fmaxf(roughness, bsdf->alpha_x);
   bsdf->alpha_y = fmaxf(roughness, bsdf->alpha_y);
@@ -376,7 +383,7 @@ ccl_device void bsdf_microfacet_multi_ggx_blur(ShaderClosure *sc, float roughnes
 
 /* Multiscattering GGX Glossy closure */
 
-ccl_device int bsdf_microfacet_multi_ggx_common_setup(MicrofacetBsdf *bsdf)
+ccl_device int bsdf_microfacet_multi_ggx_common_setup(ccl_private MicrofacetBsdf *bsdf)
 {
   bsdf->alpha_x = clamp(bsdf->alpha_x, 1e-4f, 1.0f);
   bsdf->alpha_y = clamp(bsdf->alpha_y, 1e-4f, 1.0f);
@@ -386,7 +393,7 @@ ccl_device int bsdf_microfacet_multi_ggx_common_setup(MicrofacetBsdf *bsdf)
   return SD_BSDF | SD_BSDF_HAS_EVAL | SD_BSDF_NEEDS_LCG;
 }
 
-ccl_device int bsdf_microfacet_multi_ggx_setup(MicrofacetBsdf *bsdf)
+ccl_device int bsdf_microfacet_multi_ggx_setup(ccl_private MicrofacetBsdf *bsdf)
 {
   if (is_zero(bsdf->T))
     bsdf->T = make_float3(1.0f, 0.0f, 0.0f);
@@ -396,7 +403,8 @@ ccl_device int bsdf_microfacet_multi_ggx_setup(MicrofacetBsdf *bsdf)
   return bsdf_microfacet_multi_ggx_common_setup(bsdf);
 }
 
-ccl_device int bsdf_microfacet_multi_ggx_fresnel_setup(MicrofacetBsdf *bsdf, const ShaderData *sd)
+ccl_device int bsdf_microfacet_multi_ggx_fresnel_setup(ccl_private MicrofacetBsdf *bsdf,
+                                                       ccl_private const ShaderData *sd)
 {
   if (is_zero(bsdf->T))
     bsdf->T = make_float3(1.0f, 0.0f, 0.0f);
@@ -408,7 +416,7 @@ ccl_device int bsdf_microfacet_multi_ggx_fresnel_setup(MicrofacetBsdf *bsdf, con
   return bsdf_microfacet_multi_ggx_common_setup(bsdf);
 }
 
-ccl_device int bsdf_microfacet_multi_ggx_refraction_setup(MicrofacetBsdf *bsdf)
+ccl_device int bsdf_microfacet_multi_ggx_refraction_setup(ccl_private MicrofacetBsdf *bsdf)
 {
   bsdf->alpha_y = bsdf->alpha_x;
 
@@ -417,23 +425,23 @@ ccl_device int bsdf_microfacet_multi_ggx_refraction_setup(MicrofacetBsdf *bsdf)
   return bsdf_microfacet_multi_ggx_common_setup(bsdf);
 }
 
-ccl_device float3 bsdf_microfacet_multi_ggx_eval_transmit(const ShaderClosure *sc,
+ccl_device float3 bsdf_microfacet_multi_ggx_eval_transmit(ccl_private const ShaderClosure *sc,
                                                           const float3 I,
                                                           const float3 omega_in,
-                                                          float *pdf,
-                                                          ccl_addr_space uint *lcg_state)
+                                                          ccl_private float *pdf,
+                                                          ccl_private uint *lcg_state)
 {
   *pdf = 0.0f;
   return make_float3(0.0f, 0.0f, 0.0f);
 }
 
-ccl_device float3 bsdf_microfacet_multi_ggx_eval_reflect(const ShaderClosure *sc,
+ccl_device float3 bsdf_microfacet_multi_ggx_eval_reflect(ccl_private const ShaderClosure *sc,
                                                          const float3 I,
                                                          const float3 omega_in,
-                                                         float *pdf,
-                                                         ccl_addr_space uint *lcg_state)
+                                                         ccl_private float *pdf,
+                                                         ccl_private uint *lcg_state)
 {
-  const MicrofacetBsdf *bsdf = (const MicrofacetBsdf *)sc;
+  ccl_private const MicrofacetBsdf *bsdf = (ccl_private const MicrofacetBsdf *)sc;
 
   if (bsdf->alpha_x * bsdf->alpha_y < 1e-7f) {
     return make_float3(0.0f, 0.0f, 0.0f);
@@ -468,22 +476,22 @@ ccl_device float3 bsdf_microfacet_multi_ggx_eval_reflect(const ShaderClosure *sc
                         bsdf->extra->cspec0);
 }
 
-ccl_device int bsdf_microfacet_multi_ggx_sample(const KernelGlobals *kg,
-                                                const ShaderClosure *sc,
+ccl_device int bsdf_microfacet_multi_ggx_sample(ccl_global const KernelGlobals *kg,
+                                                ccl_private const ShaderClosure *sc,
                                                 float3 Ng,
                                                 float3 I,
                                                 float3 dIdx,
                                                 float3 dIdy,
                                                 float randu,
                                                 float randv,
-                                                float3 *eval,
-                                                float3 *omega_in,
-                                                float3 *domega_in_dx,
-                                                float3 *domega_in_dy,
-                                                float *pdf,
-                                                ccl_addr_space uint *lcg_state)
+                                                ccl_private float3 *eval,
+                                                ccl_private float3 *omega_in,
+                                                ccl_private float3 *domega_in_dx,
+                                                ccl_private float3 *domega_in_dy,
+                                                ccl_private float *pdf,
+                                                ccl_private uint *lcg_state)
 {
-  const MicrofacetBsdf *bsdf = (const MicrofacetBsdf *)sc;
+  ccl_private const MicrofacetBsdf *bsdf = (ccl_private const MicrofacetBsdf *)sc;
 
   float3 X, Y, Z;
   Z = bsdf->N;
@@ -536,7 +544,7 @@ ccl_device int bsdf_microfacet_multi_ggx_sample(const KernelGlobals *kg,
 
 /* Multiscattering GGX Glass closure */
 
-ccl_device int bsdf_microfacet_multi_ggx_glass_setup(MicrofacetBsdf *bsdf)
+ccl_device int bsdf_microfacet_multi_ggx_glass_setup(ccl_private MicrofacetBsdf *bsdf)
 {
   bsdf->alpha_x = clamp(bsdf->alpha_x, 1e-4f, 1.0f);
   bsdf->alpha_y = bsdf->alpha_x;
@@ -548,8 +556,8 @@ ccl_device int bsdf_microfacet_multi_ggx_glass_setup(MicrofacetBsdf *bsdf)
   return SD_BSDF | SD_BSDF_HAS_EVAL | SD_BSDF_NEEDS_LCG;
 }
 
-ccl_device int bsdf_microfacet_multi_ggx_glass_fresnel_setup(MicrofacetBsdf *bsdf,
-                                                             const ShaderData *sd)
+ccl_device int bsdf_microfacet_multi_ggx_glass_fresnel_setup(ccl_private MicrofacetBsdf *bsdf,
+                                                             ccl_private const ShaderData *sd)
 {
   bsdf->alpha_x = clamp(bsdf->alpha_x, 1e-4f, 1.0f);
   bsdf->alpha_y = bsdf->alpha_x;
@@ -564,13 +572,14 @@ ccl_device int bsdf_microfacet_multi_ggx_glass_fresnel_setup(MicrofacetBsdf *bsd
   return SD_BSDF | SD_BSDF_HAS_EVAL | SD_BSDF_NEEDS_LCG;
 }
 
-ccl_device float3 bsdf_microfacet_multi_ggx_glass_eval_transmit(const ShaderClosure *sc,
-                                                                const float3 I,
-                                                                const float3 omega_in,
-                                                                float *pdf,
-                                                                ccl_addr_space uint *lcg_state)
+ccl_device float3
+bsdf_microfacet_multi_ggx_glass_eval_transmit(ccl_private const ShaderClosure *sc,
+                                              const float3 I,
+                                              const float3 omega_in,
+                                              ccl_private float *pdf,
+                                              ccl_private uint *lcg_state)
 {
-  const MicrofacetBsdf *bsdf = (const MicrofacetBsdf *)sc;
+  ccl_private const MicrofacetBsdf *bsdf = (ccl_private const MicrofacetBsdf *)sc;
 
   if (bsdf->alpha_x * bsdf->alpha_y < 1e-7f) {
     return make_float3(0.0f, 0.0f, 0.0f);
@@ -596,13 +605,13 @@ ccl_device float3 bsdf_microfacet_multi_ggx_glass_eval_transmit(const ShaderClos
                        bsdf->extra->color);
 }
 
-ccl_device float3 bsdf_microfacet_multi_ggx_glass_eval_reflect(const ShaderClosure *sc,
+ccl_device float3 bsdf_microfacet_multi_ggx_glass_eval_reflect(ccl_private const ShaderClosure *sc,
                                                                const float3 I,
                                                                const float3 omega_in,
-                                                               float *pdf,
-                                                               ccl_addr_space uint *lcg_state)
+                                                               ccl_private float *pdf,
+                                                               ccl_private uint *lcg_state)
 {
-  const MicrofacetBsdf *bsdf = (const MicrofacetBsdf *)sc;
+  ccl_private const MicrofacetBsdf *bsdf = (ccl_private const MicrofacetBsdf *)sc;
 
   if (bsdf->alpha_x * bsdf->alpha_y < 1e-7f) {
     return make_float3(0.0f, 0.0f, 0.0f);
@@ -630,22 +639,22 @@ ccl_device float3 bsdf_microfacet_multi_ggx_glass_eval_reflect(const ShaderClosu
                        bsdf->extra->cspec0);
 }
 
-ccl_device int bsdf_microfacet_multi_ggx_glass_sample(const KernelGlobals *kg,
-                                                      const ShaderClosure *sc,
+ccl_device int bsdf_microfacet_multi_ggx_glass_sample(ccl_global const KernelGlobals *kg,
+                                                      ccl_private const ShaderClosure *sc,
                                                       float3 Ng,
                                                       float3 I,
                                                       float3 dIdx,
                                                       float3 dIdy,
                                                       float randu,
                                                       float randv,
-                                                      float3 *eval,
-                                                      float3 *omega_in,
-                                                      float3 *domega_in_dx,
-                                                      float3 *domega_in_dy,
-                                                      float *pdf,
-                                                      ccl_addr_space uint *lcg_state)
+                                                      ccl_private float3 *eval,
+                                                      ccl_private float3 *omega_in,
+                                                      ccl_private float3 *domega_in_dx,
+                                                      ccl_private float3 *domega_in_dy,
+                                                      ccl_private float *pdf,
+                                                      ccl_private uint *lcg_state)
 {
-  const MicrofacetBsdf *bsdf = (const MicrofacetBsdf *)sc;
+  ccl_private const MicrofacetBsdf *bsdf = (ccl_private const MicrofacetBsdf *)sc;
 
   float3 X, Y, Z;
   Z = bsdf->N;