[Backport to 20] Add SPV_INTEL_int4 extension (KhronosGroup#3178) (KhronosGroup#3294)

MrSidims · vmaksimo · web-flow · commit 4b0b8fd395cd · 2025-08-07T13:59:58.000+02:00
Adds support for native 4-bit type. Spec: https://github.com/KhronosGroup/SPIRV-Registry/blob/main/extensions/INTEL/SPV_INTEL_int4.asciidoc Signed-off-by: Sidorov, Dmitry <dmitry.sidorov@intel.com> Co-authored-by: Viktoria Maximova <viktoria.maksimova@intel.com>
diff --git a/include/LLVMSPIRVExtensions.inc b/include/LLVMSPIRVExtensions.inc
@@ -78,3 +78,5 @@ EXT(SPV_INTEL_bindless_images)
 EXT(SPV_INTEL_2d_block_io)
 EXT(SPV_INTEL_subgroup_matrix_multiply_accumulate)
 EXT(SPV_KHR_bfloat16)
+EXT(SPV_INTEL_ternary_bitwise_function)
+EXT(SPV_INTEL_int4)
diff --git a/lib/SPIRV/SPIRVWriter.cpp b/lib/SPIRV/SPIRVWriter.cpp
@@ -391,7 +391,10 @@ SPIRVType *LLVMToSPIRVBase::transType(Type *T) {
     if (BM->isAllowedToUseExtension(
             ExtensionID::SPV_INTEL_arbitrary_precision_integers) ||
         BM->getErrorLog().checkError(
-            BitWidth == 8 || BitWidth == 16 || BitWidth == 32 || BitWidth == 64,
+            (BitWidth == 4 &&
+             BM->isAllowedToUseExtension(ExtensionID::SPV_INTEL_int4)) ||
+                BitWidth == 8 || BitWidth == 16 || BitWidth == 32 ||
+                BitWidth == 64,
             SPIRVEC_InvalidBitWidth, std::to_string(BitWidth))) {
       return mapType(T, BM->addIntegerType(T->getIntegerBitWidth()));
     }
diff --git a/lib/SPIRV/libSPIRV/SPIRVEnum.h b/lib/SPIRV/libSPIRV/SPIRVEnum.h
@@ -226,6 +226,8 @@ template <> inline void SPIRVMap<SPIRVCapabilityKind, SPIRVCapVec>::init() {
   ADD_VEC_INIT(CapabilityBFloat16DotProductKHR, {CapabilityBFloat16TypeKHR});
   ADD_VEC_INIT(CapabilityBFloat16CooperativeMatrixKHR,
                {CapabilityBFloat16TypeKHR, CapabilityCooperativeMatrixKHR});
+  ADD_VEC_INIT(CapabilityInt4CooperativeMatrixINTEL,
+               {CapabilityInt4TypeINTEL, CapabilityCooperativeMatrixKHR});
 }
 
 template <> inline void SPIRVMap<SPIRVExecutionModelKind, SPIRVCapVec>::init() {
diff --git a/lib/SPIRV/libSPIRV/SPIRVNameMapEnum.h b/lib/SPIRV/libSPIRV/SPIRVNameMapEnum.h
@@ -682,6 +682,8 @@ template <> inline void SPIRVMap<Capability, std::string>::init() {
       "SubgroupRequirementsINTEL");
   add(internal::CapabilityTaskSequenceINTEL, "TaskSequenceINTEL");
   add(internal::CapabilityBindlessImagesINTEL, "BindlessImagesINTEL");
+  add(CapabilityInt4TypeINTEL, "Int4TypeINTEL");
+  add(CapabilityInt4CooperativeMatrixINTEL, "Int4CooperativeMatrixINTEL");
 }
 SPIRV_DEF_NAMEMAP(Capability, SPIRVCapabilityNameMap)
 
diff --git a/lib/SPIRV/libSPIRV/SPIRVType.h b/lib/SPIRV/libSPIRV/SPIRVType.h
@@ -155,6 +155,14 @@ class SPIRVTypeInt : public SPIRVType {
   SPIRVCapVec getRequiredCapability() const override {
     SPIRVCapVec CV;
     switch (BitWidth) {
+    case 4: {
+      if (Module->isAllowedToUseExtension(ExtensionID::SPV_INTEL_int4)) {
+        CV.push_back(CapabilityInt4TypeINTEL);
+        return CV;
+      }
+      CV.push_back(CapabilityArbitraryPrecisionIntegersINTEL);
+      return CV;
+    }
     case 8:
       CV.push_back(CapabilityInt8);
       break;
@@ -175,6 +183,11 @@ class SPIRVTypeInt : public SPIRVType {
   }
   std::optional<ExtensionID> getRequiredExtension() const override {
     switch (BitWidth) {
+    case 4: {
+      if (Module->isAllowedToUseExtension(ExtensionID::SPV_INTEL_int4))
+        return ExtensionID::SPV_INTEL_int4;
+      return ExtensionID::SPV_INTEL_arbitrary_precision_integers;
+    }
     case 8:
     case 16:
     case 32:
@@ -189,7 +202,9 @@ class SPIRVTypeInt : public SPIRVType {
   _SPIRV_DEF_ENCDEC3(Id, BitWidth, IsSigned)
   void validate() const override {
     SPIRVEntry::validate();
-    assert((BitWidth == 8 || BitWidth == 16 || BitWidth == 32 ||
+    assert(((BitWidth == 4 &&
+             Module->isAllowedToUseExtension(ExtensionID::SPV_INTEL_int4)) ||
+            BitWidth == 8 || BitWidth == 16 || BitWidth == 32 ||
             BitWidth == 64 ||
             Module->isAllowedToUseExtension(
                 ExtensionID::SPV_INTEL_arbitrary_precision_integers)) &&
@@ -1219,12 +1234,18 @@ class SPIRVTypeCooperativeMatrixKHR : public SPIRVType {
   SPIRVTypeCooperativeMatrixKHR();
   _SPIRV_DCL_ENCDEC
   std::optional<ExtensionID> getRequiredExtension() const override {
+    SPIRVType *Ty = this->getCompType();
+    if (Ty->isTypeInt() && static_cast<SPIRVTypeInt *>(Ty)->getBitWidth() == 4)
+      this->getModule()->addExtension(ExtensionID::SPV_INTEL_int4);
     return ExtensionID::SPV_KHR_cooperative_matrix;
   }
   SPIRVCapVec getRequiredCapability() const override {
     auto CV = getVec(CapabilityCooperativeMatrixKHR);
     if (CompType->isTypeFloat(16, FPEncodingBFloat16KHR))
       CV.push_back(CapabilityBFloat16CooperativeMatrixKHR);
+    else if (CompType->isTypeInt() &&
+             static_cast<SPIRVTypeInt *>(CompType)->getBitWidth() == 4)
+      CV.push_back(CapabilityInt4CooperativeMatrixINTEL);
     return CV;
   }
 
diff --git a/spirv-headers-tag.conf b/spirv-headers-tag.conf
@@ -1 +1 @@
-0e710677989b4326ac974fd80c5308191ed80965
+c9aad99f9276817f18f72a4696239237c83cb775
diff --git a/test/extensions/INTEL/SPV_INTEL_int4/cooperative_matrix.ll b/test/extensions/INTEL/SPV_INTEL_int4/cooperative_matrix.ll
@@ -0,0 +1,31 @@
+; RUN: llvm-as < %s -o %t.bc
+; RUN: llvm-spirv %t.bc --spirv-ext=+SPV_KHR_cooperative_matrix,+SPV_INTEL_int4 -o %t.spv
+; RUN: llvm-spirv %t.spv -to-text -o %t.spt
+; RUN: FileCheck < %t.spt %s --check-prefix=CHECK-SPIRV
+
+; RUN: llvm-spirv -r %t.spv -o %t.rev.bc
+; RUN: llvm-dis < %t.rev.bc | FileCheck %s --check-prefix=CHECK-LLVM
+
+; CHECK-SPIRV-DAG: Capability Int4TypeINTEL
+; CHECK-SPIRV-DAG: Capability CooperativeMatrixKHR
+; CHECK-SPIRV-DAG: Extension "SPV_INTEL_int4"
+; CHECK-SPIRV-DAG: Capability Int4CooperativeMatrixINTEL
+; CHECK-SPIRV-DAG: Extension "SPV_KHR_cooperative_matrix"
+; CHECK-SPIRV-DAG: TypeInt [[#Int4Ty:]] 4 0
+; CHECK-SPIRV-DAG: TypeCooperativeMatrixKHR [[#CoopMatTy:]] [[#Int4Ty]] [[#]] [[#]] [[#]] [[#]]
+; CHECK-SPIRV-DAG: CompositeConstruct [[#CoopMatTy]]
+
+; CHECK-LLVM: call spir_func target("spirv.CooperativeMatrixKHR", i4, 3, 12, 12, 2) @_Z26__spirv_CompositeConstructi(i4 0)
+
+; ModuleID = 'matrix-int4-test.bc'
+source_filename = "matrix-int4-test.cpp"
+target datalayout = "e-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024-n8:16:32:64"
+target triple = "spir64-unknown-unknown"
+
+define spir_kernel void @foo() {
+entry:
+  %call.i.i = tail call spir_func noundef target("spirv.CooperativeMatrixKHR", i4, 3, 12, 12, 2) @_Z26__spirv_CompositeConstruct(i4 noundef 0)
+  ret void
+}
+
+declare dso_local spir_func noundef target("spirv.CooperativeMatrixKHR", i4, 3, 12, 12, 2) @_Z26__spirv_CompositeConstruct(i4 noundef)
diff --git a/test/extensions/INTEL/SPV_INTEL_int4/negative.ll b/test/extensions/INTEL/SPV_INTEL_int4/negative.ll
@@ -0,0 +1,41 @@
+; RUN: llvm-as < %s -o %t.bc
+; RUN: llvm-spirv %t.bc --spirv-ext=+SPV_INTEL_arbitrary_precision_integers -o %t.spv
+; RUN: llvm-spirv %t.spv -to-text -o %t.spt
+; RUN: FileCheck < %t.spt %s --check-prefix=CHECK-SPIRV
+; RUN: llvm-spirv -r %t.spv -o %t.rev.bc
+; RUN: llvm-dis < %t.rev.bc | FileCheck %s --check-prefix=CHECK-LLVM
+
+; RUN: not llvm-spirv %t.bc 2>&1 | FileCheck %s --check-prefix=CHECK-ERROR
+; CHECK-ERROR: InvalidBitWidth: Invalid bit width in input: 4
+
+; CHECK-SPIRV: Capability ArbitraryPrecisionIntegersINTEL
+; CHECK-SPIRV: Extension "SPV_INTEL_arbitrary_precision_integers"
+; CHECK-SPIRV: TypeInt [[#Int4:]] 4 0
+; CHECK-SPIRV: Constant [[#Int4]] [[#Const:]] 1
+; CHECK-SPIRV: TypeFunction [[#]] [[#]] [[#Int4]]
+; CHECK-SPIRV: TypePointer [[#Int4PtrTy:]] [[#]] [[#Int4]]
+; CHECK-SPIRV: Variable [[#Int4PtrTy]] [[#Int4Ptr:]]
+; CHECK-SPIRV: Store [[#Int4Ptr]] [[#Const]]
+; CHECK-SPIRV: Load [[#Int4]] [[#Load:]] [[#Int4Ptr]]
+; CHECK-SPIRV: FunctionCall [[#]] [[#]] [[#]] [[#Load]]
+
+; CHECK-LLVM: %[[#Alloc:]] = alloca i4, align 1
+; CHECK-LLVM: store i4 1, ptr %[[#Alloc:]], align 1
+; CHECK-LLVM: %[[#Load:]] = load i4, ptr %[[#Alloc]], align 1
+; CHECK-LLVM: call spir_func void @boo(i4 %[[#Load]])
+
+
+target datalayout = "e-p:32:32-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024"
+target triple = "spir-unknown-unknown"
+
+; Function Attrs: nounwind
+define spir_kernel void @foo() {
+entry:
+  %0 = alloca i4
+  store i4 1, ptr %0
+  %1 = load i4, ptr %0
+  call spir_func void @boo(i4 %1)
+  ret void
+}
+
+declare spir_func void @boo(i4)
diff --git a/test/extensions/INTEL/SPV_INTEL_int4/trivial.ll b/test/extensions/INTEL/SPV_INTEL_int4/trivial.ll
@@ -0,0 +1,38 @@
+; RUN: llvm-as < %s -o %t.bc
+; RUN: llvm-spirv %t.bc --spirv-ext=+SPV_INTEL_int4 -o %t.spv
+; RUN: llvm-spirv %t.spv -to-text -o %t.spt
+; RUN: FileCheck < %t.spt %s --check-prefix=CHECK-SPIRV
+; RUN: llvm-spirv -r %t.spv -o %t.rev.bc
+; RUN: llvm-dis < %t.rev.bc | FileCheck %s --check-prefix=CHECK-LLVM
+
+; CHECK-SPIRV: Capability Int4TypeINTEL
+; CHECK-SPIRV: Extension "SPV_INTEL_int4"
+; CHECK-SPIRV: TypeInt [[#Int4:]] 4 0
+; CHECK-SPIRV: Constant [[#Int4]] [[#Const:]] 1
+; CHECK-SPIRV: TypeFunction [[#]] [[#]] [[#Int4]]
+; CHECK-SPIRV: TypePointer [[#Int3PtrTy:]] [[#]] [[#Int4]]
+; CHECK-SPIRV: Variable [[#Int3PtrTy]] [[#Int3Ptr:]]
+; CHECK-SPIRV: Store [[#Int3Ptr]] [[#Const]]
+; CHECK-SPIRV: Load [[#Int4]] [[#Load:]] [[#Int3Ptr]]
+; CHECK-SPIRV: FunctionCall [[#]] [[#]] [[#]] [[#Load]]
+
+; CHECK-LLVM: %[[#Alloc:]] = alloca i4, align 1
+; CHECK-LLVM: store i4 1, ptr %[[#Alloc:]], align 1
+; CHECK-LLVM: %[[#Load:]] = load i4, ptr %[[#Alloc]], align 1
+; CHECK-LLVM: call spir_func void @boo(i4 %[[#Load]])
+
+
+target datalayout = "e-p:32:32-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024"
+target triple = "spir-unknown-unknown"
+
+; Function Attrs: nounwind
+define spir_kernel void @foo() {
+entry:
+  %0 = alloca i4
+  store i4 1, ptr %0
+  %1 = load i4, ptr %0
+  call spir_func void @boo(i4 %1)
+  ret void
+}
+
+declare spir_func void @boo(i4)

Original file line number	Diff line number	Diff line change
`@@ -226,6 +226,8 @@ template <> inline void SPIRVMap<SPIRVCapabilityKind, SPIRVCapVec>::init() {`
`226`	`226`	`ADD_VEC_INIT(CapabilityBFloat16DotProductKHR, {CapabilityBFloat16TypeKHR});`
`227`	`227`	`ADD_VEC_INIT(CapabilityBFloat16CooperativeMatrixKHR,`
`228`	`228`	`{CapabilityBFloat16TypeKHR, CapabilityCooperativeMatrixKHR});`
	`229`	`+ ADD_VEC_INIT(CapabilityInt4CooperativeMatrixINTEL,`
	`230`	`+ {CapabilityInt4TypeINTEL, CapabilityCooperativeMatrixKHR});`
`229`	`231`	`}`
`230`	`232`
`231`	`233`	`template <> inline void SPIRVMap<SPIRVExecutionModelKind, SPIRVCapVec>::init() {`
Original file line number	Diff line number	Diff line change
`@@ -682,6 +682,8 @@ template <> inline void SPIRVMap<Capability, std::string>::init() {`
`682`	`682`	`"SubgroupRequirementsINTEL");`
`683`	`683`	`add(internal::CapabilityTaskSequenceINTEL, "TaskSequenceINTEL");`
`684`	`684`	`add(internal::CapabilityBindlessImagesINTEL, "BindlessImagesINTEL");`
	`685`	`+ add(CapabilityInt4TypeINTEL, "Int4TypeINTEL");`
	`686`	`+ add(CapabilityInt4CooperativeMatrixINTEL, "Int4CooperativeMatrixINTEL");`
`685`	`687`	`}`
`686`	`688`	`SPIRV_DEF_NAMEMAP(Capability, SPIRVCapabilityNameMap)`
`687`	`689`
Original file line number	Diff line number	Diff line change
`@@ -1 +1 @@`
`1`		`-0e710677989b4326ac974fd80c5308191ed80965`
	`1`	`+c9aad99f9276817f18f72a4696239237c83cb775`