SPIR-V image operations (#3163)

* Add __truncate and __sampledType for spirv_asm

Allows some texture tests to start passing

* add __isVector

Currently unused

* Add 1-vector legalization pass (WIP)

* Add capabilities for image types

* neaten instruction dumping

* add 1-vector test

* Add a couple of cases to vec1 legalization

* Remove texture tests from expected failures

* comment

* regenerate vs projects

* Remove redundant define form synchapi emulation

* refactoring image methods

* All sample functions refactored

* Remove incorrect glsl intrinsics

Partially addresses https://github.com/shader-slang/slang/issues/3174

* __subscript image ops via writing funcs

* Extract texture struct writing from core.meta.slang

* Abstract out cuda intrinsic

* Remvoe erroneous call to opDecorateIndex

* spirv asm IR utils

* Correct position of loads for SPIR-V asm inst operands

* Raise constructors to global scope during spir-v legalization

* Correct snippet output

* Implement most texture sampling ops for SPIR-V

* Legalize 1-vectors for glsl too

* Make SPIR-V inst operands non-hoistable

* Better 1-vector legalization

* Put textures in ptrs for spirv

* insert missing break

* Add vec1 legalization test

* Add some missing pieces to slang-ir-insts

* Greatly neaten vec1 legalization

* a

* Neaten vec1 legalization

* Add image read and write intrinsics for spir-v

* Squash warnings

* regenerate vs projects

* Drop redundant guards

* Drop 5 tests from expected failure list

* Inst numbering changes to cross compile tests

* vec1 legalization tests only on vk

* Correct location of asm op emit

* Inline constant in spirv-asm

* Correct signedness for lane in wave intrinsics

* Extract element from float1 for cuda

* squash warnings

* Neaten spirv-emit

* dedupe more capabilities

* warnings

* neaten assert

* comments

* comments

1 files changed, 18 insertions, 5 deletions

diff --git a/source/slang/slang-parser.cpp b/source/slang/slang-parser.cpp
index c3eba8c58..306d2cbec 100644
--- a/source/slang/slang-parser.cpp
+++ b/source/slang/slang-parser.cpp
@@ -6310,6 +6310,19 @@ namespace Slang
         {
             return SPIRVAsmOperand{SPIRVAsmOperand::ResultMarker, parser->ReadToken()};
         }
+        // The handy __sampledType function
+        if(AdvanceIf(parser, "__sampledType"))
+        {
+            parser->ReadToken(TokenType::LParent);
+            const auto typeExpr = parser->ParseType();
+            parser->ReadMatchingToken(TokenType::RParent);
+            return SPIRVAsmOperand{SPIRVAsmOperand::SampledType, Token{}, typeExpr};
+        }
+        // The pseudo-operand for component truncation
+        else if(parser->LookAheadToken("__truncate"))
+        {
+            return SPIRVAsmOperand{SPIRVAsmOperand::TruncateMarker, parser->ReadToken()};
+        }
         else if (AdvanceIf(parser, "builtin"))
         {
             // reference to a builtin var.
@@ -6325,7 +6338,6 @@ namespace Slang
         {
             return SPIRVAsmOperand{ SPIRVAsmOperand::GLSL450Set, parser->ReadToken() };
         }
-
         // A regular identifier
         else if(parser->LookAheadToken(TokenType::Identifier))
         {
@@ -6362,7 +6374,8 @@ namespace Slang
         // A $foo variable
         else if(AdvanceIf(parser, TokenType::Dollar))
         {
-            return slangIdentOperand(SPIRVAsmOperand::SlangValue);
+            Expr* expr = parseAtomicExpr(parser);
+            return SPIRVAsmOperand{SPIRVAsmOperand::SlangValue, Token{}, expr};
         }
         // A $$foo type
         else if(AdvanceIf(parser, TokenType::DollarDollar))
@@ -6465,7 +6478,7 @@ namespace Slang
             || resultOperand)
         {
             // Insert the LHS result-type operand
-            if(ret.operands.getCount() == opInfo->resultTypeIndex && resultTypeOperand)
+            if(opInfo && ret.operands.getCount() == opInfo->resultTypeIndex && resultTypeOperand)
             {
                 ret.operands.add(*resultTypeOperand);
                 resultTypeOperand.reset();
@@ -6473,14 +6486,14 @@ namespace Slang
             }
 
             // Insert the LHS result operand
-            if(ret.operands.getCount() == opInfo->resultIdIndex && resultOperand)
+            if(opInfo && ret.operands.getCount() == opInfo->resultIdIndex && resultOperand)
             {
                 ret.operands.add(*resultOperand);
                 resultOperand.reset();
                 continue;
             }
 
-            if(ret.operands.getCount() == opInfo->maxOperandCount)
+            if(opInfo && ret.operands.getCount() == opInfo->maxOperandCount)
             {
                 parser->diagnose(
                     parser->tokenReader.peekLoc(),