Implement non member function atomic texture support (#4544)

* Implement non member function atomic texture support texture_buffer and texture1d

Fixes: #4538
Related to: #4291, fixes `tests/compute/atomics-buffer.slang`

Texture objects cannot use `__getMetalAtomicRef` to cast objects into atomic value type. [Texture objects mandate use of member functions](https://developer.apple.com/metal/Metal-Shading-Language-Specification.pdf#Texture%20Functions). The implementation is as follows:
* We can detect texture object usage through checking for an `IRImageSubscript` Operation. `__isTextureAccess()` was added to evaluate if we have an `IRImageSubscript` operation at compile time (before `static_assert`). `__isTextureAccess()` only checks if we are targeting Metal.
* We have all parameter data needed to call a texture atomic function embedded inside `IRImageSubscript`. `__extractTextureFromTextureAccess()` and `__extractCoordFromTextureAccess()` was added to extract this data for use with Metal atomics.

Note:
* Metal documentation has various incorrect details (function names)
* Since we currently hardcode metal versions for compiling, the Metal compiler version was changed to target `Metal 3.1` (`slang-gcc-compiler-util.cpp`)
* textures do not permit atomic float operations

* add fallthrough attribute + fix bug with 'exchange instead of xor' + fix warning bug

* incorrect function name fix

* missing filecheck

* disable atomics-buffer.slang compute test since GFX issue causing it to fail

* Array support for metal interlockedAtomic and proper verification of texture with interlockedAtomic functions

* Array support for metal interlockedAtomic
* proper verification of texture with interlockedAtomic functions
note: had to seperate many functions to allow forceInlining to run

* missing getOperand(0)

* push atomic fix for metal

* fix atomic syntax for metal and hlsl emitting extra brackets (breaks tests)

* test changes and meta changes

1. max is 8 rw textures with metal because Metal has this limit. Split up tests to not hit this limit
2. added back `[0]`...,`T` to test since this legalizes metal atomic intrinsic

* macro'ify some of the atomic code

1. addresses review
2. makes code easier to modify in the future (rather than sifting through 1000 lines we can just look at ~10-30

* fix test 'check'

* missing float support due to macro

* add functions macro generates, `InternalAtomicOperationInfo`

---------

Co-authored-by: Yong He <yonghe@outlook.com>

2 files changed, 28 insertions, 0 deletions

diff --git a/tests/compute/atomics-buffer.slang b/tests/compute/atomics-buffer.slang
index 72b86368d..6745d6b58 100644
--- a/tests/compute/atomics-buffer.slang
+++ b/tests/compute/atomics-buffer.slang
@@ -9,7 +9,11 @@
 //DISABLE_TEST(compute):COMPARE_COMPUTE_EX:-slang -compute -cuda -shaderobj
 // Atomics not available on CPU currently
 //DISABLE_TEST(compute):COMPARE_COMPUTE_EX:-slang -compute -cpu -shaderobj
+// RWBuffer does not work with the GFX backend as expected with Metal
 //DISABLE_TEST(compute):COMPARE_COMPUTE:-slang -shaderobj -mtl
+//TEST:SIMPLE(filecheck=METALLIB): -target metallib -stage compute -entry computeMain
+
+//METALLIB: @computeMain
 
 //TEST_INPUT:ubuffer(format=R_UInt32, data=[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]):out,name outputBuffer
 
diff --git a/tests/compute/atomics-invalid-dest-type.slang b/tests/compute/atomics-invalid-dest-type.slang
new file mode 100644
index 000000000..864debaee
--- /dev/null
+++ b/tests/compute/atomics-invalid-dest-type.slang
@@ -0,0 +1,24 @@
+// atomics-buffer.slang
+
+//TEST:SIMPLE(filecheck=CHECK): -target spirv -stage compute -entry computeMain
+//TEST:SIMPLE(filecheck=CHECK): -target hlsl -stage compute -entry computeMain
+//TEST:SIMPLE(filecheck=CHECK): -target glsl -stage compute -entry computeMain
+//TEST:SIMPLE(filecheck=CHECK): -target metal -stage compute -entry computeMain
+
+//CHECK: Atomic must be applied to a scalar texture or non-texture
+
+RWBuffer<uint2> outputBuffer;
+
+void test(uint val)
+{
+    uint originalValue;
+
+	InterlockedAdd(outputBuffer[val][0], val, originalValue);
+}
+
+[numthreads(4, 1, 1)]
+void computeMain(uint3 dispatchThreadID : SV_DispatchThreadID)
+{
+    uint tid = dispatchThreadID.x;
+    test(tid);
+}