[CBP] Pointer frontend changes + groupshared pointer support (#7848)

Resolves #7628
Resolves: #8197

Primary Goals:
1. Add `Access` to pointer
2. AddressSpace::GroupShared support for pointers (SPIR-V)
3. Add `__getAddress()` to replace `&`
* `&` is not updated to `require(cpu)` since slangpy uses `&`. This
means we must: (1) merge PR; (2) replace `&` with `__getAddress()`; (3)
add `require(cpu)` to `&`

Changes:
* Added to `Ptr` the `Access` generic argument & logic (for
`Access::Read`).
* Moved the generic argument `AddressSpace` from `Ptr` to the end of the
type.
* Added pointer casting support between any `Ptr` as long as the
`AddressSpace` is the same
* Disallow globallycoherent T* and coherent T*
* Disallow const T*, T const*, and const T*
* Fixed .natvis display of `ConstantValue` `ValOperandNode`
* Support generic resolution of type-casted integers
* Added `VariablePointer` emitting for spirv + other minor logic needed
for groupshared pointers

Breaking Changes:
* Anyone using the `AddressSpace` of `Ptr` will now have to account for
the `Access` argument
* we disallow various syntax paired with `Ptr` and `T*`

---------

Co-authored-by: slangbot <186143334+slangbot@users.noreply.github.com>

3 files changed, 74 insertions, 0 deletions

diff --git a/tests/language-feature/pointer/pointer-access/pointer-access-frontend.slang b/tests/language-feature/pointer/pointer-access/pointer-access-frontend.slang
new file mode 100644
index 000000000..98a2a076d
--- /dev/null
+++ b/tests/language-feature/pointer/pointer-access/pointer-access-frontend.slang
@@ -0,0 +1,14 @@
+//TEST:SIMPLE(filecheck=CHECK):-stage compute -entry computeMain -target spirv
+
+//CHECK: OpEntryPoint
+//CHECK-NOT: error
+
+int* processMemory;
+int* output;
+
+[numthreads(1, 1, 1)]
+void computeMain(int id : SV_DispatchThreadID)
+{
+    Ptr<int, Access::ReadWrite, AddressSpace::Device> ptr1 = processMemory + id.x + 5;
+    Ptr<int> ptr2 = processMemory + id.x + 4;
+}
\ No newline at end of file
diff --git a/tests/language-feature/pointer/pointer-access/read-only-pointer-1.slang b/tests/language-feature/pointer/pointer-access/read-only-pointer-1.slang
new file mode 100644
index 000000000..e7f1ad534
--- /dev/null
+++ b/tests/language-feature/pointer/pointer-access/read-only-pointer-1.slang
@@ -0,0 +1,41 @@
+//TEST:SIMPLE(filecheck=CHECK):-stage compute -entry computeMain -target spirv
+
+// Writing with a read-only pointer should be an error
+
+int* processMemory;
+RWStructuredBuffer<int> output;
+
+typealias ReadPtr = Ptr<int, Access::Read, AddressSpace::Device>;
+
+void writeToReadOnlyPointer(ReadPtr ptr)
+{
+    // CHECK: ([[# @LINE+1]]): error 30011
+    ptr[0] = 1;
+}
+
+void writeToReadOnlyPointerOut(out int ptrVal)
+{
+    ptrVal = 1;
+}
+
+[numthreads(1, 1, 1)]
+void computeMain(int id : SV_DispatchThreadID)
+{
+    // CHECK-NOT: ([[# @LINE+1]]): error
+    ReadPtr ptr1 = ReadPtr(processMemory + id.x);
+
+    // CHECK: ([[# @LINE+1]]): error 30011
+    ptr1[id + 1] = 1;
+    // CHECK: ([[# @LINE+1]]): error 30011
+    *ptr1 = 1;
+
+    writeToReadOnlyPointer(ptr1);
+
+    // CHECK: ([[# @LINE+1]]): error 30047
+    writeToReadOnlyPointerOut(ptr1[1]);
+
+    // CHECK: ([[# @LINE+1]]): error 30047
+    writeToReadOnlyPointerOut(*(ptr1+2));
+    
+    output[id] = ptr1[id];
+}
diff --git a/tests/language-feature/pointer/pointer-access/read-only-pointer-2.slang b/tests/language-feature/pointer/pointer-access/read-only-pointer-2.slang
new file mode 100644
index 000000000..c5288caba
--- /dev/null
+++ b/tests/language-feature/pointer/pointer-access/read-only-pointer-2.slang
@@ -0,0 +1,19 @@
+//TEST:SIMPLE(filecheck=CHECK):-stage compute -entry computeMain -target spirv
+
+// Tests valid use of read-only pointer
+
+// CHECK: OpEntryPoint
+// CHECK-NOT: error
+
+int* processMemory;
+int* output;
+
+typealias ReadPtr = Ptr<int, Access::Read, AddressSpace::Device>;
+
+[numthreads(1, 1, 1)]
+void computeMain(int id : SV_DispatchThreadID)
+{
+    ReadPtr ptr1 = ReadPtr(processMemory + id.x);
+
+    output[id] = ptr1[id];
+}