https://github.com/aobolensk updated 
https://github.com/llvm/llvm-project/pull/222018

>From ef08c6bd700dec6001269f2d9676a79ea2064d72 Mon Sep 17 00:00:00 2001
From: Arseniy Obolenskiy <[email protected]>
Date: Tue, 8 Sep 2026 16:49:31 +0200
Subject: [PATCH 1/3] [CIR][SPIR-V] Dispatch AMDGPU builtins on AMDGCN-flavored
 SPIR-V

---
 clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp       | 10 +++
 clang/lib/CIR/CodeGen/Targets/SPIRV.cpp       |  5 ++
 .../CIR/CodeGenHIP/amdgcnspirv-builtins.hip   | 79 +++++++++++++++++++
 3 files changed, 94 insertions(+)
 create mode 100644 clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip

diff --git a/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp 
b/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
index d4c17d3c5f24f3..bf64d966fa0bb3 100644
--- a/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenBuiltin.cpp
@@ -3005,6 +3005,9 @@ RValue CIRGenFunction::emitBuiltinExpr(const GlobalDecl 
&gd, unsigned builtinID,
       llvm::Triple::getArchTypePrefix(getTarget().getTriple().getArch());
   if (!prefix.empty()) {
     intrinsicID = Intrinsic::getIntrinsicForClangBuiltin(prefix, name);
+    if (intrinsicID == Intrinsic::not_intrinsic && prefix == "spv" &&
+        getTarget().getTriple().getOS() == llvm::Triple::OSType::AMDHSA)
+      intrinsicID = Intrinsic::getIntrinsicForClangBuiltin("amdgcn", name);
     // NOTE we don't need to perform a compatibility flag check here since the
     // intrinsics are declared in Builtins*.def via LANGBUILTIN which filter 
the
     // MS builtins via ALL_MS_LANGUAGES and are filtered earlier.
@@ -3193,6 +3196,13 @@ emitTargetArchBuiltinExpr(CIRGenFunction *cgf, unsigned 
builtinID,
   case llvm::Triple::riscv32:
   case llvm::Triple::riscv64:
     return cgf->emitRISCVBuiltinExpr(builtinID, e);
+  case llvm::Triple::spirv32:
+  case llvm::Triple::spirv64:
+    if (cgf->getTarget().getTriple().getOS() == llvm::Triple::OSType::AMDHSA)
+      return cgf->emitAMDGPUBuiltinExpr(builtinID, e);
+    [[fallthrough]];
+  case llvm::Triple::spirv:
+    return std::nullopt;
   default:
     return std::nullopt;
   }
diff --git a/clang/lib/CIR/CodeGen/Targets/SPIRV.cpp 
b/clang/lib/CIR/CodeGen/Targets/SPIRV.cpp
index 7b66c51af640c6..4d19f122799e3b 100644
--- a/clang/lib/CIR/CodeGen/Targets/SPIRV.cpp
+++ b/clang/lib/CIR/CodeGen/Targets/SPIRV.cpp
@@ -43,6 +43,11 @@ class CommonSPIRTargetCIRGenInfo : public TargetCIRGenInfo {
     return cir::CallingConv::SpirKernel;
   }
 
+  bool supportsLibCall() const override {
+    const llvm::Triple &triple = getABIInfo().cgt.getCGModule().getTriple();
+    return !(triple.isSPIRV() && triple.getVendor() == llvm::Triple::AMD);
+  }
+
   void setCUDAKernelCallingConvention(const FunctionType *&ft) const override {
     // Convert HIP kernels to SPIR-V kernels.
     if (getABIInfo().cgt.getASTContext().getLangOpts().HIP)
diff --git a/clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip 
b/clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip
new file mode 100644
index 00000000000000..8bcde14d1787cc
--- /dev/null
+++ b/clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip
@@ -0,0 +1,79 @@
+// REQUIRES: amdgpu-registered-target
+// RUN: %clang_cc1 -triple spirv64-amd-amdhsa -x hip -fclangir \
+// RUN:            -fcuda-is-device -emit-cir %s -o %t.cir
+// RUN: FileCheck --check-prefix=CIR %s --input-file=%t.cir
+
+// RUN: %clang_cc1 -triple spirv64-amd-amdhsa -x hip -fclangir \
+// RUN:            -fcuda-is-device -emit-llvm %s -o %t-cir.ll
+// RUN: FileCheck --check-prefix=LLVM %s --input-file=%t-cir.ll
+
+// RUN: %clang_cc1 -triple spirv64-amd-amdhsa -x hip \
+// RUN:            -fcuda-is-device -emit-llvm %s -o %t.ll
+// RUN: FileCheck --check-prefix=OGCG %s --input-file=%t.ll
+
+// Test that AMDGPU builtins are available on AMDGCN-flavored SPIR-V.
+
+#define __device__ __attribute__((device))
+
+__device__ int test_readfirstlane(int x) {
+  return __builtin_amdgcn_readfirstlane(x);
+}
+
+// CIR-LABEL: cir.func no_inline @_Z18test_readfirstlanei
+// CIR: cir.call_llvm_intrinsic "amdgcn.readfirstlane" {{.*}} : (!s32i) -> 
!s32i
+
+// LLVM-LABEL: define spir_func noundef i32 @_Z18test_readfirstlanei
+// LLVM: call{{.*}} @llvm.amdgcn.readfirstlane.i32
+
+// OGCG-LABEL: define spir_func noundef i32 @_Z18test_readfirstlanei
+// OGCG: addrspacecast ptr %{{.*}} to ptr addrspace(4)
+// OGCG: call{{.*}} @llvm.amdgcn.readfirstlane.i32
+
+__device__ float test_rcp(float x) {
+  return __builtin_amdgcn_rcpf(x);
+}
+
+// CIR-LABEL: cir.func no_inline @_Z8test_rcpf
+// CIR: cir.call_llvm_intrinsic "amdgcn.rcp" {{.*}} : (!cir.float) -> 
!cir.float
+
+// LLVM-LABEL: define spir_func noundef float @_Z8test_rcpf
+// LLVM: call{{.*}} @llvm.amdgcn.rcp.f32
+
+// OGCG-LABEL: define spir_func noundef float @_Z8test_rcpf
+// OGCG: call contract{{.*}} @llvm.amdgcn.rcp.f32
+
+// Reached through the generic clang-builtin-to-intrinsic mapping, which has to
+// retry the "amdgcn" prefix after "spv" fails to match.
+
+__device__ unsigned test_wavefrontsize() {
+  return __builtin_amdgcn_wavefrontsize();
+}
+
+// CIR-LABEL: cir.func no_inline @_Z18test_wavefrontsizev
+// CIR: cir.call_llvm_intrinsic "amdgcn.wavefrontsize" : () -> !u32i
+
+// LLVM-LABEL: define spir_func noundef i32 @_Z18test_wavefrontsizev
+// LLVM: call{{.*}} @llvm.amdgcn.wavefrontsize()
+
+// OGCG-LABEL: define spir_func noundef i32 @_Z18test_wavefrontsizev
+// OGCG: call{{.*}} @llvm.amdgcn.wavefrontsize()
+
+// Expanded inline rather than emitted as a libm call, because SPIR-V with an
+// AMD vendor has no device libm.
+
+__device__ float test_logb(float x) {
+  return __builtin_logbf(x);
+}
+
+// CIR-LABEL: cir.func no_inline @_Z9test_logbf
+// CIR: cir.call_llvm_intrinsic "frexp" %{{.*}} : (!cir.float) -> 
!rec_anon_struct
+
+// LLVM-LABEL: define spir_func noundef float @_Z9test_logbf
+// LLVM: call{{.*}} @llvm.frexp.f32.i32
+// LLVM: add i32 %{{.*}}, -1
+
+// OGCG-LABEL: define spir_func noundef float @_Z9test_logbf
+// OGCG: call{{.*}} @llvm.frexp.f32.i32
+// OGCG: add nsw i32 %{{.*}}, -1
+// OGCG: load float, ptr addrspace(4) %{{.*}}
+// OGCG: call contract{{.*}} @llvm.fabs.f32

>From bc3bb5a2ea831cfddb40cec107182e42419e5acf Mon Sep 17 00:00:00 2001
From: Arseniy Obolenskiy <[email protected]>
Date: Mon, 28 Sep 2026 20:27:47 +0200
Subject: [PATCH 2/3] address part of the comments

---
 clang/lib/CIR/CodeGen/CIRGenBuiltinAMDGPU.cpp      | 5 +++--
 clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip | 5 ++++-
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/clang/lib/CIR/CodeGen/CIRGenBuiltinAMDGPU.cpp 
b/clang/lib/CIR/CodeGen/CIRGenBuiltinAMDGPU.cpp
index 1c23ea142bf8dc..4c1c4dd9de0f30 100644
--- a/clang/lib/CIR/CodeGen/CIRGenBuiltinAMDGPU.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenBuiltinAMDGPU.cpp
@@ -89,7 +89,8 @@ static mlir::Value emitLogbBuiltin(CIRGenFunction &cgf, const 
CallExpr *e,
 
   mlir::Value negativeOne =
       builder.getConstant(loc, cir::IntAttr::get(int32Ty, -1));
-  mlir::Value expMinus1 = builder.createAdd(loc, exp, negativeOne);
+  mlir::Value expMinus1 = builder.createAdd(
+      loc, exp, negativeOne, cir::OverflowBehavior::NoSignedWrap);
 
   mlir::Value siToFp = cir::CastOp::create(
       builder, loc, srcTy, cir::CastKind::int_to_float, expMinus1);
@@ -100,7 +101,7 @@ static mlir::Value emitLogbBuiltin(CIRGenFunction &cgf, 
const CallExpr *e,
   mlir::Value inf = builder.getConstant(loc, cir::FPAttr::get(srcTy, infVal));
 
   mlir::Value fabsNegInf =
-      builder.createCompare(loc, cir::CmpOpKind::ne, fabs, inf);
+      builder.createCompare(loc, cir::CmpOpKind::one, fabs, inf);
 
   mlir::Value sel = builder.createSelect(loc, fabsNegInf, siToFp, fabs);
 
diff --git a/clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip 
b/clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip
index 8bcde14d1787cc..36bd58d3f1231a 100644
--- a/clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip
+++ b/clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip
@@ -70,10 +70,13 @@ __device__ float test_logb(float x) {
 
 // LLVM-LABEL: define spir_func noundef float @_Z9test_logbf
 // LLVM: call{{.*}} @llvm.frexp.f32.i32
-// LLVM: add i32 %{{.*}}, -1
+// LLVM: add nsw i32 %{{.*}}, -1
+// LLVM: call{{.*}} @llvm.fabs.f32
+// LLVM: fcmp one float %{{.*}}, +inf
 
 // OGCG-LABEL: define spir_func noundef float @_Z9test_logbf
 // OGCG: call{{.*}} @llvm.frexp.f32.i32
 // OGCG: add nsw i32 %{{.*}}, -1
 // OGCG: load float, ptr addrspace(4) %{{.*}}
 // OGCG: call contract{{.*}} @llvm.fabs.f32
+// OGCG: fcmp contract one float %{{.*}}, +inf

>From f34ce4f206666e503e08e5af9c25055cb837d565 Mon Sep 17 00:00:00 2001
From: Arseniy Obolenskiy <[email protected]>
Date: Tue, 29 Sep 2026 11:10:50 +0200
Subject: [PATCH 3/3] fixme

---
 clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip 
b/clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip
index 36bd58d3f1231a..3f0e91672d8a5f 100644
--- a/clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip
+++ b/clang/test/CIR/CodeGenHIP/amdgcnspirv-builtins.hip
@@ -13,6 +13,13 @@
 
 // Test that AMDGPU builtins are available on AMDGCN-flavored SPIR-V.
 
+// FIXME: CIR doesn't propagate the 'contract' fast-math flag to LLVM IR yet,
+// so the LLVM check lines use call{{.*}} to tolerate the difference between
+// CIR (no flags) and classic codegen ('contract').
+
+// FIXME: CIR doesn't cast allocas to the generic address space yet, so the
+// LLVM output lacks the addrspacecast that classic codegen emits.
+
 #define __device__ __attribute__((device))
 
 __device__ int test_readfirstlane(int x) {

_______________________________________________
cfe-commits mailing list
[email protected]
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits

Reply via email to