From 75d65d36608cf4653490f0a04a17d1ee057b47a6 Mon Sep 17 00:00:00 2001
From: Yong He <yonghe@outlook.com>
Date: Mon, 18 Nov 2024 15:21:13 -0800
Subject: [PATCH] Remove "GL_EXT_samplerless_texture_functions" from combined
 sampler functions. (#5585)

---
 source/slang/hlsl.meta.slang   | 41 +++++++++++++++++++++-------------
 tests/glsl/sampler-fetch.slang | 20 +++++++++++++++++
 2 files changed, 46 insertions(+), 15 deletions(-)
 create mode 100644 tests/glsl/sampler-fetch.slang

diff --git a/source/slang/hlsl.meta.slang b/source/slang/hlsl.meta.slang
index 90b2a17b93..babb1ae20e 100644
--- a/source/slang/hlsl.meta.slang
+++ b/source/slang/hlsl.meta.slang
@@ -3029,7 +3029,6 @@ extension _Texture<T,Shape,isArray,0,sampleCount,0,isShadow,isCombined,format>
     static const int isMS = 0;
     static const int access = $(kCoreModule_ResourceAccessReadOnly);
 //@public:
-    __glsl_extension(GL_EXT_samplerless_texture_functions)
     [__readNone]
     [require(glsl, texture_sm_4_1_samplerless)]
     T __glsl_load(vector<int, Shape.dimensions+isArray> location)
@@ -3037,7 +3036,6 @@ extension _Texture<T,Shape,isArray,0,sampleCount,0,isShadow,isCombined,format>
         __intrinsic_asm "$ctexelFetch($0, ($1), 0)$z";
     }
 
-    __glsl_extension(GL_EXT_samplerless_texture_functions)
     [__readNone]
     [ForceInline]
     [require(cpp_glsl_hlsl_metal_spirv_wgsl, texture_sm_4_1_samplerless)]
@@ -3110,6 +3108,8 @@ extension _Texture<T,Shape,isArray,0,sampleCount,0,isShadow,isCombined,format>
             static_assert(false, "Unsupported 'Load' of 'texture' for 'metal' target");
             __intrinsic_asm "<invalid intrinsics>";
         case glsl:
+            if (isCombined == 0)
+                __requireGLSLExtension("GL_EXT_samplerless_texture_functions");
             __intrinsic_asm "$ctexelFetch($0, ($1).$w1b, ($1).$w1e)$z";
         case spirv:
             const int lodLoc = Shape.dimensions+isArray;
@@ -3161,7 +3161,6 @@ extension _Texture<T,Shape,isArray,0,sampleCount,0,isShadow,isCombined,format>
         }
     }
 
-    __glsl_extension(GL_EXT_samplerless_texture_functions)
     [__readNone]
     [ForceInline]
     [require(cpp_glsl_hlsl_spirv, texture_sm_4_1_samplerless)]
@@ -3171,9 +3170,11 @@ extension _Texture<T,Shape,isArray,0,sampleCount,0,isShadow,isCombined,format>
         {
             case cpp:
             case hlsl:
-            __intrinsic_asm ".Load";
+                __intrinsic_asm ".Load";
             case glsl:
-            __intrinsic_asm "$ctexelFetchOffset($0, ($1).$w1b, ($1).$w1e, ($2))$z";
+                if (isCombined == 0)
+                    __requireGLSLExtension("GL_EXT_samplerless_texture_functions");
+                __intrinsic_asm "$ctexelFetchOffset($0, ($1).$w1b, ($1).$w1e, ($2))$z";
             case spirv:
                 const int lodLoc = Shape.dimensions+isArray;
                 let coord = __vectorReshape<Shape.dimensions+isArray>(location);
@@ -3214,7 +3215,6 @@ extension _Texture<T,Shape,isArray,0,sampleCount,0,isShadow,isCombined,format>
 
     __subscript(vector<uint, Shape.dimensions+isArray> location) -> T
     {
-        __glsl_extension(GL_EXT_samplerless_texture_functions)
         [__readNone]
         [ForceInline]
         [require(cpp_glsl_hlsl_metal_spirv_wgsl, texture_sm_4_1_samplerless)]
@@ -3228,6 +3228,8 @@ extension _Texture<T,Shape,isArray,0,sampleCount,0,isShadow,isCombined,format>
                 case metal:
                     return Load(__makeVector(location, 0));
                 case glsl:
+                    if (isCombined == 0)
+                        __requireGLSLExtension("GL_EXT_samplerless_texture_functions");
                     return __glsl_load(location);
                 case spirv:
                     if (isCombined != 0)
@@ -3263,7 +3265,6 @@ extension _Texture<T,Shape,isArray,1,sampleCount,0,isShadow,isCombined,format>
     static const int access = $(kCoreModule_ResourceAccessReadOnly);
     static const int isMS = 1;
 //@public:
-    __glsl_extension(GL_EXT_samplerless_texture_functions)
     [__readNone]
     [ForceInline]
     [require(cpp_glsl_hlsl_metal_spirv_wgsl, texture_sm_4_1_samplerless)]
@@ -3303,6 +3304,8 @@ extension _Texture<T,Shape,isArray,1,sampleCount,0,isShadow,isCombined,format>
                 // TODO: This needs to be handled by the capability system
                 __intrinsic_asm "<Not supported>";
             case glsl:
+                if (isCombined == 0)
+                    __requireGLSLExtension("GL_EXT_samplerless_texture_functions");
                 __intrinsic_asm "$ctexelFetch($0, $1, ($2))$z";
             case spirv:
                 if (isCombined != 0)
@@ -3340,7 +3343,6 @@ extension _Texture<T,Shape,isArray,1,sampleCount,0,isShadow,isCombined,format>
         return Load(__vectorReshape<Shape.dimensions + isArray>(locationAndSampleIndex), locationAndSampleIndex[Shape.dimensions + isArray]);
     }
 
-    __glsl_extension(GL_EXT_samplerless_texture_functions)
     [__readNone]
     [ForceInline]
     [require(cpp_glsl_hlsl_spirv, texture_sm_4_1_samplerless)]
@@ -3352,6 +3354,8 @@ extension _Texture<T,Shape,isArray,1,sampleCount,0,isShadow,isCombined,format>
             case hlsl:
                 __intrinsic_asm ".Load";
             case glsl:
+                if (isCombined == 0)
+                    __requireGLSLExtension("GL_EXT_samplerless_texture_functions");
                 __intrinsic_asm "$ctexelFetchOffset($0, $1, ($2), ($3))$z";
             case spirv:
                 if (isCombined != 0)
@@ -3390,7 +3394,6 @@ extension _Texture<T,Shape,isArray,1,sampleCount,0,isShadow,isCombined,format>
 
     __subscript(vector<uint, Shape.dimensions+isArray> location) -> T
     {
-        __glsl_extension(GL_EXT_samplerless_texture_functions)
         [__readNone]
         [ForceInline]
         [require(cpp_glsl_hlsl_metal_spirv_wgsl, texture_sm_4_1_samplerless)]
@@ -3402,16 +3405,18 @@ extension _Texture<T,Shape,isArray,1,sampleCount,0,isShadow,isCombined,format>
                 case hlsl:
                     __intrinsic_asm "($0).sample[$1]";
                 case metal:
-                case glsl:
                 case spirv:
                 case wgsl:
                     return Load(location, 0);
+                case glsl:
+                    if (isCombined == 0)
+                        __requireGLSLExtension("GL_EXT_samplerless_texture_functions");
+                    return Load(location, 0);
             }
         }
     }
     __subscript(vector<uint, Shape.dimensions+isArray> location, int sampleIndex) -> T
     {
-        __glsl_extension(GL_EXT_samplerless_texture_functions)
         [__readNone]
         [ForceInline]
         [require(cpp_glsl_hlsl_metal_spirv_wgsl, texture_sm_4_1_samplerless)]
@@ -3423,10 +3428,13 @@ extension _Texture<T,Shape,isArray,1,sampleCount,0,isShadow,isCombined,format>
                 case hlsl:
                     __intrinsic_asm "($0).sample[$2][$1]";
                 case metal:
-                case glsl:
                 case spirv:
                 case wgsl:
                     return Load(location, sampleIndex);
+                case glsl:
+                    if (isCombined == 0)
+                        __requireGLSLExtension("GL_EXT_samplerless_texture_functions");
+                    return Load(location, sampleIndex);
             }
         }
     }
@@ -15027,7 +15035,9 @@ extension _Texture<T, __ShapeBuffer, 0, 0, 0, $(aa), 0, 0, format>
         __target_switch
         {
         case hlsl: __intrinsic_asm ".GetDimensions";
-        case glsl: __intrinsic_asm "($1 = $(glslTextureSizeFunc)($0))";
+        case glsl:
+            __requireGLSLExtension("GL_EXT_samplerless_texture_functions");
+            __intrinsic_asm "($1 = $(glslTextureSizeFunc)($0))";
         case metal: __intrinsic_asm "(*($1) = $0.get_width())";
         case spirv:
             dim = spirv_asm {
@@ -15037,7 +15047,6 @@ extension _Texture<T, __ShapeBuffer, 0, 0, 0, $(aa), 0, 0, format>
         }
     }
 
-    __glsl_extension(GL_EXT_samplerless_texture_functions)
     $(isReadOnly?"[__readNone] ":"")
     $(requireToSet)
     T Load(int location)
@@ -15046,7 +15055,9 @@ extension _Texture<T, __ShapeBuffer, 0, 0, 0, $(aa), 0, 0, format>
         {
         case hlsl: __intrinsic_asm ".Load";
         case metal: __intrinsic_asm "$c$0.read(uint($1))$z";
-        case glsl: __intrinsic_asm "$(glslLoadFuncName)($0, $1)$z";
+        case glsl:
+            __requireGLSLExtension("GL_EXT_samplerless_texture_functions");
+            __intrinsic_asm "$(glslLoadFuncName)($0, $1)$z";
         case spirv: return spirv_asm {
                 %sampled:__sampledType(T) = $(spvLoadInstName) $this $location;
                 __truncate $$T result __sampledType(T) %sampled;
diff --git a/tests/glsl/sampler-fetch.slang b/tests/glsl/sampler-fetch.slang
new file mode 100644
index 0000000000..6d6f98cd72
--- /dev/null
+++ b/tests/glsl/sampler-fetch.slang
@@ -0,0 +1,20 @@
+//TEST:SIMPLE(filecheck=CHECK): -target glsl -stage compute -entry testMain
+//TEST:SIMPLE(filecheck=SPV): -target spirv -stage compute -entry testMain -emit-spirv-via-glsl
+
+// We shouldn't be using GL_EXT_samplerless_texture_functions extension.
+// CHECK-NOT: GL_EXT_samplerless_texture_functions
+
+// SPV: OpImageFetch
+
+Sampler2D sampler;
+
+RWStructuredBuffer<float4> outputBuffer;
+
+[NumThreads(1,1,1)]
+void testMain()
+{
+    uint w, h, l;
+    sampler.GetDimensions(0, w, h, l);
+    var result = sampler.Load(int3(1,1,1), int2(1,2));
+    outputBuffer[0] = result + float(w);
+}
\ No newline at end of file