[Mlir-commits] [clang] [mlir] [CIR][mlir][ABI] Add IndirectAliased (byref) argument lowering (PR #230415)
llvmlistbot at llvm.org
llvmlistbot at llvm.org
Fri Oct 23 22:22:27 PDT 2026
https://github.com/skc7 updated https://github.com/llvm/llvm-project/pull/230415
>From 33ea6e4f610a687cafc8f868b0680eb97408bf5e Mon Sep 17 00:00:00 2001
From: skc7 <Krishna.Sankisa at amd.com>
Date: Fri, 9 Oct 2026 14:13:57 +0530
Subject: [PATCH 1/4] [CIR][mlir][ABI] Add IndirectAliased (byref) argument
lowering
---
.../Transforms/CallConvLoweringPass.cpp | 11 +-
.../TargetLowering/CIRABIRewriteContext.cpp | 173 +++++++++++-----
.../byval-sret-arg-attr-lowering.cir | 15 ++
.../abi-lowering/indirect-aliased-nyi.cir | 64 ++++++
.../abi-lowering/indirect-aliased.cir | 196 ++++++++++++++++++
mlir/include/mlir/ABI/ABIRewriteContext.h | 19 +-
.../mlir/ABI/Targets/Test/TestTarget.h | 5 +-
mlir/lib/ABI/Targets/Test/TestTarget.cpp | 22 +-
mlir/unittests/ABI/ABIRewriteContextTest.cpp | 10 +
mlir/unittests/ABI/TestTargetTest.cpp | 48 +++++
10 files changed, 497 insertions(+), 66 deletions(-)
create mode 100644 clang/test/CIR/Transforms/abi-lowering/indirect-aliased-nyi.cir
create mode 100644 clang/test/CIR/Transforms/abi-lowering/indirect-aliased.cir
diff --git a/clang/lib/CIR/Dialect/Transforms/CallConvLoweringPass.cpp b/clang/lib/CIR/Dialect/Transforms/CallConvLoweringPass.cpp
index e18a2cb5d07d76..199824d55f4e06 100644
--- a/clang/lib/CIR/Dialect/Transforms/CallConvLoweringPass.cpp
+++ b/clang/lib/CIR/Dialect/Transforms/CallConvLoweringPass.cpp
@@ -587,6 +587,9 @@ static const llvm::abi::Type *mapCIRType(mlir::Type type,
/// wide to fit (a `_BitInt` over 128 bits), is passed via a pointer (sret
/// for returns, byval for arguments).
///
+/// IndirectAliased: an argument passed as a pointer to the caller's object
+/// with no copy implied (byref), in the address space the classifier names.
+///
/// Ignore: a void return, or an empty record dropped from the signature.
static std::optional<ArgClassification>
convertABIArgInfo(const llvm::abi::ArgInfo &info, MLIRContext *ctx,
@@ -687,6 +690,9 @@ convertABIArgInfo(const llvm::abi::ArgInfo &info, MLIRContext *ctx,
return ArgClassification::getIndirect(info.getIndirectAlign(),
info.getIndirectByVal(),
info.getIndirectAddrSpace());
+ if (info.isIndirectAliased())
+ return ArgClassification::getIndirectAliased(info.getIndirectAlign(),
+ info.getIndirectAddrSpace());
// AArch64 pure scalable aggregates use CoerceAndExpand. This bridge lowers
// x86_64 classifications only.
assert(!info.isCoerceAndExpand() &&
@@ -856,12 +862,13 @@ CIRABIClassifierCommon::classifyVariadicCall(
}
/// Whether \p fc gives the callee access to memory through a pointer the ABI
-/// introduced: an sret slot for an indirect return, or an indirect argument.
+/// introduced: an sret slot for an indirect return, or an indirect or byref
+/// argument.
static bool hasIndirectSlot(const FunctionClassification &fc) {
if (fc.returnInfo.kind == ArgKind::Indirect)
return true;
return llvm::any_of(fc.argInfos, [](const ArgClassification &ac) {
- return ac.kind == ArgKind::Indirect;
+ return ac.kind == ArgKind::Indirect || ac.kind == ArgKind::IndirectAliased;
});
}
diff --git a/clang/lib/CIR/Dialect/Transforms/TargetLowering/CIRABIRewriteContext.cpp b/clang/lib/CIR/Dialect/Transforms/TargetLowering/CIRABIRewriteContext.cpp
index 46e06b814776f3..cd290457f3565c 100644
--- a/clang/lib/CIR/Dialect/Transforms/TargetLowering/CIRABIRewriteContext.cpp
+++ b/clang/lib/CIR/Dialect/Transforms/TargetLowering/CIRABIRewriteContext.cpp
@@ -28,7 +28,8 @@ using namespace mlir::abi;
// This rewrite context supports the Direct (with or without coercion),
// Extend, Ignore, Indirect-return (sret), Indirect-argument (byval and
-// non-byval), and Expand (struct flattening) classifications.
+// non-byval), IndirectAliased-argument (byref), and Expand (struct
+// flattening) classifications.
//
// An Indirect argument is byval or not, following its classification's
// byVal flag. byval is a by-value parameter the ABI passes in memory rather
@@ -44,6 +45,10 @@ using namespace mlir::abi;
// rewires that slot to the incoming pointer so the body mutates the caller's
// storage in place.
//
+// A byref argument is lowered like byval, apart from its attribute and the
+// address space of its pointer. The callee must not write through that
+// pointer, so it fills the CIRGen param slot with a copy just as byval does.
+//
// For Expand, the single struct argument is replaced by N scalar arguments
// (one per field). At the callee, the N field block arguments are stored
// directly into the parameter's own alloca (the CIRGen spill slot). At the
@@ -60,6 +65,22 @@ using namespace mlir::abi;
namespace {
+/// A pointer to \p pointee in target address space \p addrSpace. Zero is the
+/// default address space, which carries no attribute.
+cir::PointerType getPtrTyInAddrSpace(mlir::Type pointee, unsigned addrSpace) {
+ mlir::ptr::MemorySpaceAttrInterface asAttr;
+ if (addrSpace)
+ asAttr = cir::TargetAddressSpaceAttr::get(pointee.getContext(), addrSpace);
+ return cir::PointerType::get(pointee, asAttr);
+}
+
+/// The pointer passed in place of a byref value of type \p pointee.
+cir::PointerType getByRefPtrTy(mlir::Type pointee,
+ const ArgClassification &ac) {
+ assert(ac.kind == ArgKind::IndirectAliased && "expected a byref argument");
+ return getPtrTyInAddrSpace(pointee, ac.indirectAddrSpace);
+}
+
/// Return the coerced RecordType for a Direct classification that should be
/// flattened into individual scalar arguments, or a null type if the
/// classification does not call for flattening.
@@ -82,7 +103,8 @@ cir::RecordType getFlattenedCoercedType(const ArgClassification &ac) {
/// Build the new argument-type list for a function whose ABI classification
/// is \p fc. Handles Direct (with or without coercion), Extend, Ignore,
-/// Indirect (byval and non-byval), and Expand (struct flattening) arguments.
+/// Indirect (byval and non-byval), IndirectAliased (byref), and Expand
+/// (struct flattening) arguments.
/// The sret return pointer, when present, is prepended by
/// rewriteFunctionDefinition rather than here.
mlir::LogicalResult
@@ -135,6 +157,9 @@ buildNewArgTypes(ArrayRef<mlir::Type> oldArgTypes,
case ArgKind::Indirect:
newArgTypes.push_back(cir::PointerType::get(origTy));
break;
+ case ArgKind::IndirectAliased:
+ newArgTypes.push_back(getByRefPtrTy(origTy, ac));
+ break;
}
}
return mlir::success();
@@ -142,8 +167,8 @@ buildNewArgTypes(ArrayRef<mlir::Type> oldArgTypes,
/// Compute the new return type for a function whose return classification
/// is \p retInfo. Direct returns keep (or coerce to) their type, Ignore and
-/// Indirect (sret) returns become void, Extend keeps its type; Expand emits
-/// an error.
+/// Indirect (sret) returns become void, Extend keeps its type; Expand and
+/// IndirectAliased emit an error.
mlir::Type
computeNewReturnType(mlir::Type origRetTy, const ArgClassification &retInfo,
mlir::MLIRContext *ctx,
@@ -159,6 +184,10 @@ computeNewReturnType(mlir::Type origRetTy, const ArgClassification &retInfo,
emitError() << "Expand return is not allowed (classic codegen rejects "
<< "it in EmitFunctionEpilog)";
return nullptr;
+ case ArgKind::IndirectAliased:
+ emitError() << "IndirectAliased return is not allowed (classic codegen "
+ << "rejects it in EmitFunctionEpilog)";
+ return nullptr;
case ArgKind::Extend:
// Same convention as Extend args: keep the original return type in the
// signature; the sign/zero extension is communicated via the
@@ -199,25 +228,27 @@ static bool isCoercionWiderThanMemory(mlir::Type origTy, mlir::Type coercedTy,
}
/// Whether updateArgAttrs has anything to change: an arg that is Ignore (its
-/// slot is dropped), Extend (needs llvm.signext / llvm.zeroext), Indirect
-/// (needs the pointer attributes), Expand (changes the argument count), or a
-/// coerced Direct, which may be flattened or may lose llvm.noundef.
+/// slot is dropped), Extend (needs llvm.signext / llvm.zeroext), Indirect or
+/// IndirectAliased (needs the pointer attributes), Expand (changes the argument
+/// count), or a coerced Direct, which may be flattened or may lose
+/// llvm.noundef.
static bool needsArgAttrUpdate(const FunctionClassification &fc) {
return llvm::any_of(fc.argInfos, [](const ArgClassification &ac) {
return ac.kind == ArgKind::Ignore || ac.kind == ArgKind::Extend ||
- ac.kind == ArgKind::Indirect || ac.kind == ArgKind::Expand ||
+ ac.kind == ArgKind::Indirect ||
+ ac.kind == ArgKind::IndirectAliased || ac.kind == ArgKind::Expand ||
(ac.kind == ArgKind::Direct && ac.coercedType);
});
}
/// Build an updated arg_attrs ArrayAttr that drops Ignore'd args, adds
/// llvm.signext / llvm.zeroext on Extend args, adds the pointer attributes
-/// for Indirect args in place of llvm.nofpclass, drops llvm.noundef from a
-/// coerced Direct arg that passes undefined bits, gives each field of a
-/// Direct+canFlatten argument the argument's attributes, and gives each field
-/// of an Expand argument an empty dict. Direct and Extend slots keep their
-/// other existing attributes. \p origArgTypes provides the pre-rewrite type
-/// for each arg slot.
+/// for Indirect args in place of llvm.nofpclass and for IndirectAliased args,
+/// drops llvm.noundef from a coerced Direct arg that passes undefined bits,
+/// gives each field of a Direct+canFlatten argument the argument's attributes,
+/// and gives each field of an Expand argument an empty dict. Direct and
+/// Extend slots keep their other existing attributes. \p origArgTypes
+/// provides the pre-rewrite type for each arg slot.
mlir::ArrayAttr updateArgAttrs(mlir::MLIRContext *ctx,
ArrayRef<mlir::Type> origArgTypes,
mlir::ArrayAttr existingArgAttrs,
@@ -290,6 +321,16 @@ mlir::ArrayAttr updateArgAttrs(mlir::MLIRContext *ctx,
dl.getTypeSize(pointeeTy).getFixedValue()));
}
newArgAttrs.push_back(attrs.getDictionary(ctx));
+ } else if (ac.kind == ArgKind::IndirectAliased) {
+ // llvm.byref(T) records the pre-rewrite arg type, as llvm.byval does.
+ mlir::NamedAttrList attrs(existing);
+ attrs.set(mlir::LLVM::LLVMDialect::getAlignAttrName(),
+ builder.getI64IntegerAttr(ac.indirectAlign.value()));
+ attrs.set(mlir::LLVM::LLVMDialect::getNoUndefAttrName(),
+ builder.getUnitAttr());
+ attrs.set(mlir::LLVM::LLVMDialect::getByRefAttrName(),
+ mlir::TypeAttr::get(origArgTypes[oldIdx]));
+ newArgAttrs.push_back(attrs.getDictionary(ctx));
} else {
newArgAttrs.push_back(existing);
}
@@ -893,28 +934,28 @@ static cir::LoadOp getWholeRecordLoad(mlir::Value recordVal) {
/// Returns \p load if the address it read from can be passed in place of the
/// loaded value for an indirect argument that needs \p minAlign alignment,
-/// and null otherwise, including when \p load is null. A byval argument
-/// also needs storageUnwrittenBetween. On null the caller reports a
-/// non-byval argument or fills a byval slot of its own.
+/// and null otherwise, including when \p load is null. A byval or byref
+/// argument also needs storageUnwrittenBetween. On null the caller reports a
+/// non-byval argument or fills a slot of its own.
///
-/// The address has to be a pointer to the loaded type in the default address
-/// space, since that is what the rewritten parameter is, and a cir.load pins
-/// the pointee type without pinning the address space. The storage it names
-/// has to be a slot allocated here, reached through storage-preserving casts,
-/// already stating at least \p minAlign. The enclosing function's own
-/// non-byval parameter qualifies as well, since its slot stands until
-/// finalizeParameterSlots and prepareNonByvalParameters has restated it with
-/// the alignment that parameter promises rather than the one CIRGen chose
-/// for a local copy. A byval parameter's slot keeps CIRGen's alignment, so
-/// it qualifies only where that already covers \p minAlign.
+/// The address has to have \p paramTy, the rewritten parameter's type, since a
+/// cir.load pins the pointee type without pinning the address space. The
+/// storage it names has to be a slot allocated here, reached through
+/// storage-preserving casts, already stating at least \p minAlign. The
+/// enclosing function's own non-byval parameter qualifies as well, since its
+/// slot stands until finalizeParameterSlots and prepareNonByvalParameters has
+/// restated it with the alignment that parameter promises rather than the one
+/// CIRGen chose for a local copy. A byval or byref parameter's slot keeps
+/// CIRGen's alignment, so it qualifies only where that already covers
+/// \p minAlign.
///
/// Raising a slot's alignment here would not hold for one that stands in
/// for a parameter, since finalizeParameterSlots replaces it with the
/// incoming pointer, which promises only what the caller gave it.
static cir::LoadOp forwardableIndirectLoad(cir::LoadOp load,
+ cir::PointerType paramTy,
uint64_t minAlign) {
- if (!load || load.getAddr().getType() !=
- cir::PointerType::get(load.getResult().getType()))
+ if (!load || load.getAddr().getType() != paramTy)
return {};
cir::AllocaOp slot = cir::getUnderlyingAlloca(load.getAddr());
return slot && slot.getAlignment() >= minAlign ? load : cir::LoadOp();
@@ -1035,17 +1076,18 @@ findParamSpill(mlir::BlockArgument blockArg) {
/// For each Direct arg with a coerced type, change the block argument's type to
/// the coerced type and insert a coercion at function entry that maps it back
/// to the original type for body uses, which find a record in the coercion slot
-/// through rewireRecordUses. For each Indirect byval arg, change the block
-/// argument's type to a pointer, then replace a record's single param spill
-/// with a copy from that pointer. Without such a spill, a record's uses find
-/// it at the pointer through rewireRecordUses, and a value of any other type is
-/// loaded from the pointer at entry. For each Indirect non-byval arg, change
-/// the block argument to a pointer and queue the param-slot alloca to be
-/// replaced by it (no entry load or byte-copy) so the body operates on the
-/// caller's storage in place. For each Expand arg, replace the single struct
-/// block argument with N scalar block arguments (one per field) and store each
-/// field directly into the parameter's own alloca (the CIRGen spill slot),
-/// erasing the original whole-struct store.
+/// through rewireRecordUses. For each Indirect byval arg and each
+/// IndirectAliased arg, change the block argument's type to a pointer, then
+/// replace a record's single param spill with a copy from that pointer.
+/// Without such a spill, a record's uses find it at the pointer through
+/// rewireRecordUses, and a value of any other type is loaded from the pointer
+/// at entry. For each Indirect non-byval arg, change the block argument to a
+/// pointer and queue the param-slot alloca to be replaced by it (no entry load
+/// or byte-copy) so the body operates on the caller's storage in place. For
+/// each Expand arg, replace the single struct block argument with N scalar
+/// block arguments (one per field) and store each field directly into the
+/// parameter's own alloca (the CIRGen spill slot), erasing the original
+/// whole-struct store.
///
/// \p hasSRetArg is true when the function has an sret return (a hidden return
/// pointer is prepended as block argument 0). Expand arguments expand the
@@ -1226,16 +1268,22 @@ insertArgCoercion(mlir::FunctionOpInterface funcOp,
blockArg, blockArg, &entry, dl,
coercionOps, ac.directOffset)))
return mlir::failure();
- } else if (ac.kind == ArgKind::Indirect) {
+ } else if (ac.kind == ArgKind::Indirect ||
+ ac.kind == ArgKind::IndirectAliased) {
// byval and non-byval both lower to !cir.ptr<T>, and which it is shows
// up only in the attrs updateArgAttrs applies. Body lowering differs:
// the body addresses a byval parameter through the CIRGen slot it was
// spilled into, so that slot has to be filled from the incoming
// pointer, while a non-byval parameter's slot is replaced by the
- // pointer so the body works on the caller's storage in place.
- auto ptrTy = cir::PointerType::get(blockArg.getType());
-
- if (!ac.byVal) {
+ // pointer so the body works on the caller's storage in place. A byref
+ // parameter takes the byval path, through a pointer in its own address
+ // space.
+ bool byRef = ac.kind == ArgKind::IndirectAliased;
+ cir::PointerType ptrTy = byRef
+ ? getByRefPtrTy(blockArg.getType(), ac)
+ : cir::PointerType::get(blockArg.getType());
+
+ if (!byRef && !ac.byVal) {
// Without byval, drop the spill store and let the slot's uses read the
// incoming pointer, so the body operates on the caller's storage in
// place. A byte-copy would be wrong for non-trivially-copyable
@@ -2101,8 +2149,15 @@ CIRABIRewriteContext::rewriteCallSite(mlir::Operation *callOp,
newArgs.push_back(emitCoercion(builder, call.getLoc(), ac.coercedType,
arg, slotBlock, dl, ac.directOffset));
}
- } else if (ac.kind == ArgKind::Indirect) {
+ } else if (ac.kind == ArgKind::Indirect ||
+ ac.kind == ArgKind::IndirectAliased) {
uint64_t minAlign = ac.indirectAlign.value();
+ // The callee copies a byref object at entry, so the caller treats it
+ // like byval.
+ bool byRef = ac.kind == ArgKind::IndirectAliased;
+ bool byCopy = byRef || ac.byVal;
+ cir::PointerType ptrTy = byRef ? getByRefPtrTy(arg.getType(), ac)
+ : cir::PointerType::get(arg.getType());
// A record operand that names storage is passed from that storage
// rather than from the loaded value: a record value carries only the
@@ -2111,7 +2166,7 @@ CIRABIRewriteContext::rewriteCallSite(mlir::Operation *callOp,
// A byval _BitInt is passed from its value, since the load and the
// store below are its conversion between value and in-memory form.
cir::LoadOp srcLoad;
- if (!ac.byVal || mlir::isa<cir::RecordType>(arg.getType()))
+ if (!byCopy || mlir::isa<cir::RecordType>(arg.getType()))
srcLoad = maybeGetSimpleLoad(arg);
// A non-byval argument must name the caller's storage, so that the
@@ -2119,8 +2174,8 @@ CIRABIRewriteContext::rewriteCallSite(mlir::Operation *callOp,
// means passing the address the operand was loaded from rather than the
// loaded value, so a store to that storage after the load is visible to
// the callee. byval fills a slot below, this cannot.
- if (!ac.byVal) {
- cir::LoadOp fwdLoad = forwardableIndirectLoad(srcLoad, minAlign);
+ if (!byCopy) {
+ cir::LoadOp fwdLoad = forwardableIndirectLoad(srcLoad, ptrTy, minAlign);
if (!fwdLoad)
return call->emitOpError()
<< "non-byval indirect argument that does not name the "
@@ -2137,7 +2192,8 @@ CIRABIRewriteContext::rewriteCallSite(mlir::Operation *callOp,
// call, since the operand carries the value as of the load. A volatile
// load is not forwarded, since the copy byval takes at the call is not
// volatile.
- if (cir::LoadOp fwdLoad = forwardableIndirectLoad(srcLoad, minAlign);
+ if (cir::LoadOp fwdLoad =
+ forwardableIndirectLoad(srcLoad, ptrTy, minAlign);
fwdLoad && storageUnwrittenBetween(fwdLoad, call.getOperation(),
aliasAnalysis)) {
newArgs.push_back(fwdLoad.getAddr());
@@ -2145,21 +2201,28 @@ CIRABIRewriteContext::rewriteCallSite(mlir::Operation *callOp,
continue;
}
+ // A byref slot has to be an alloca of the parameter's own type, which
+ // only the alloca address space can hold.
+ if (byRef && ptrTy != getAllocaPtrTy(arg.getType(), dl))
+ return call->emitOpError()
+ << "byref argument outside the alloca address space that does "
+ "not name forwardable storage is not yet implemented in "
+ "CallConvLowering";
+
// Otherwise fill a slot, at the load's position when there is one so
// the copy reads the memory state the load read.
if (failed(rejectAtomicRecordLoad(call, arg)))
return mlir::failure();
if (!srcLoad)
srcLoad = maybeGetCopyableRecordLoad(arg);
- auto ptrTy = cir::PointerType::get(arg.getType());
mlir::IntegerAttr slotAlign = builder.getI64IntegerAttr(minAlign);
mlir::OpBuilder::InsertionGuard guard(builder);
if (srcLoad)
builder.setInsertionPoint(srcLoad);
- auto slot =
- cir::AllocaOp::create(builder, call.getLoc(), ptrTy,
- builder.getStringAttr("byval"), slotAlign);
+ auto slot = cir::AllocaOp::create(
+ builder, call.getLoc(), ptrTy,
+ builder.getStringAttr(byRef ? "byref" : "byval"), slotAlign);
if (srcLoad) {
auto copy = cir::CopyOp::create(builder, call.getLoc(), slot,
srcLoad.getAddr(), slotAlign,
@@ -2579,6 +2642,8 @@ CIRABIRewriteContext::rewriteVAArg(mlir::Operation *vaArgOp,
if (ac.kind == ArgKind::Indirect && !ac.byVal)
return reportVAArgNYI(op, "a non-trivially-copyable type");
+ if (ac.kind == ArgKind::IndirectAliased)
+ return reportVAArgNYI(op, "a type passed byref");
// neededInt counts 8-byte integer slots and neededSse counts 16-byte vector
// slots. Zero of both means the type travels in memory and is read
diff --git a/clang/test/CIR/Transforms/abi-lowering/byval-sret-arg-attr-lowering.cir b/clang/test/CIR/Transforms/abi-lowering/byval-sret-arg-attr-lowering.cir
index b0df1caa5416b4..ffc6ea00ceda7c 100644
--- a/clang/test/CIR/Transforms/abi-lowering/byval-sret-arg-attr-lowering.cir
+++ b/clang/test/CIR/Transforms/abi-lowering/byval-sret-arg-attr-lowering.cir
@@ -23,6 +23,12 @@
args = [ { kind = "indirect", indirect_align = 8, byval = false } ]
}
+#byref_as4_arg = {
+ return = { kind = "direct" },
+ args = [ { kind = "indirect_aliased", indirect_align = 8,
+ indirect_addr_space = 4 } ]
+}
+
#passthrough = {
return = { kind = "direct" },
args = [ ]
@@ -64,6 +70,15 @@ module attributes {
// CHECK: cir.func{{.*}} @takes_non_byval(%{{.*}}: !cir.ptr<!rec_Big> {{{.*}}llvm.dereferenceable = 24 : i64, llvm.nofreeobj, llvm.noundef{{.*}}})
// LLVM: define void @takes_non_byval(ptr nofreeobj noundef align 8 dereferenceable(24) %{{.+}})
+ // The byref argument attribute is converted like byval, on a pointer in its
+ // own address space.
+ cir.func @takes_big_byref(%arg0: !rec_Big) attributes { test_classify = #byref_as4_arg } {
+ cir.return
+ }
+
+ // CHECK: cir.func{{.*}} @takes_big_byref(%{{.*}}: !cir.ptr<!rec_Big, target_address_space(4)> {{{.*}}llvm.byref = !rec_Big{{.*}}})
+ // LLVM: define void @takes_big_byref(ptr addrspace(4) noundef byref(%struct.Big) align 8 %{{.+}})
+
// The call site's byval operand attribute is converted too.
cir.func @caller(%s: !rec_Big) attributes { test_classify = #passthrough } {
cir.call @takes_big(%s) : (!rec_Big) -> ()
diff --git a/clang/test/CIR/Transforms/abi-lowering/indirect-aliased-nyi.cir b/clang/test/CIR/Transforms/abi-lowering/indirect-aliased-nyi.cir
new file mode 100644
index 00000000000000..adcb86f35eb51e
--- /dev/null
+++ b/clang/test/CIR/Transforms/abi-lowering/indirect-aliased-nyi.cir
@@ -0,0 +1,64 @@
+// RUN: not cir-opt %s -split-input-file \
+// RUN: -cir-call-conv-lowering="classification-attr=test_classify" \
+// RUN: 2>&1 | FileCheck %s
+
+!s64i = !cir.int<s, 64>
+!rec_Big = !cir.struct<"Big" {data !s64i, data !s64i, data !s64i, data !s64i}>
+
+#byref_return = {
+ return = { kind = "indirect_aliased", indirect_align = 8 },
+ args = [ ]
+}
+
+module attributes {
+ dlti.dl_spec = #dlti.dl_spec<
+ #dlti.dl_entry<i64, dense<64>: vector<2xi64>>>
+} {
+
+ cir.func private @ret_big() -> !rec_Big
+ attributes { test_classify = #byref_return }
+
+ // CHECK: error: 'cir.func' op IndirectAliased return is not allowed
+ // CHECK-SAME: (classic codegen rejects it in EmitFunctionEpilog)
+
+}
+
+// -----
+
+!s64i = !cir.int<s, 64>
+!rec_Big = !cir.struct<"Big" {data !s64i, data !s64i, data !s64i, data !s64i}>
+
+#byref_as4 = {
+ return = { kind = "direct" },
+ args = [ { kind = "indirect_aliased", indirect_align = 8,
+ indirect_addr_space = 4 } ]
+}
+
+#passthrough = {
+ return = { kind = "direct" },
+ args = [ ]
+}
+
+module attributes {
+ dlti.dl_spec = #dlti.dl_spec<
+ #dlti.dl_entry<i64, dense<64>: vector<2xi64>>,
+ #dlti.dl_entry<"dlti.alloca_memory_space", 5 : ui64>>
+} {
+
+ cir.func private @takes_big_as4(%arg0: !rec_Big)
+ attributes { test_classify = #byref_as4 }
+
+ // A slot for the copy would be an alloca, which cannot live in address
+ // space 4.
+ cir.func @caller_as4_no_storage(%novalue: !rec_Big)
+ attributes { test_classify = #passthrough } {
+ cir.call @takes_big_as4(%novalue) : (!rec_Big) -> ()
+ cir.return
+ }
+
+ // CHECK: error: 'cir.call' op byref argument outside the alloca address
+ // CHECK-SAME: space that does not name forwardable storage is not yet
+ // CHECK-SAME: implemented in CallConvLowering
+ // CHECK-NEXT: cir.call @takes_big_as4(%novalue)
+
+}
diff --git a/clang/test/CIR/Transforms/abi-lowering/indirect-aliased.cir b/clang/test/CIR/Transforms/abi-lowering/indirect-aliased.cir
new file mode 100644
index 00000000000000..f4e5ef30ee502f
--- /dev/null
+++ b/clang/test/CIR/Transforms/abi-lowering/indirect-aliased.cir
@@ -0,0 +1,196 @@
+// RUN: cir-opt %s -split-input-file \
+// RUN: -cir-call-conv-lowering="classification-attr=test_classify" \
+// RUN: | FileCheck %s
+
+// IndirectAliased (byref) arguments with allocas in address space 5, as on
+// AMDGPU. A kernel takes its byref arguments in address space 4.
+
+!s32i = !cir.int<s, 32>
+!s64i = !cir.int<s, 64>
+!rec_Big = !cir.struct<"Big" {data !s64i, data !s64i, data !s64i, data !s64i}>
+
+#byref_as4 = {
+ return = { kind = "direct" },
+ args = [ { kind = "indirect_aliased", indirect_align = 8,
+ indirect_addr_space = 4 } ]
+}
+
+#byref_as5 = {
+ return = { kind = "direct" },
+ args = [ { kind = "indirect_aliased", indirect_align = 8,
+ indirect_addr_space = 5 } ]
+}
+
+#passthrough = {
+ return = { kind = "direct" },
+ args = [ ]
+}
+
+module attributes {
+ dlti.dl_spec = #dlti.dl_spec<
+ #dlti.dl_entry<i64, dense<64>: vector<2xi64>>,
+ #dlti.dl_entry<"dlti.alloca_memory_space", 5 : ui64>>
+} {
+
+ // The callee must not write through a byref pointer, so the CIRGen slot is
+ // filled by a copy across address spaces.
+ cir.func @kernel_field(%arg0: !rec_Big) -> !s64i
+ attributes { test_classify = #byref_as4 } {
+ %0 = cir.alloca "arg0" align(8) init
+ : !cir.ptr<!rec_Big, target_address_space(5)>
+ cir.store %arg0, %0 : !rec_Big, !cir.ptr<!rec_Big, target_address_space(5)>
+ %1 = cir.get_member %0[0] {name = "a"}
+ : !cir.ptr<!rec_Big, target_address_space(5)>
+ -> !cir.ptr<!s64i, target_address_space(5)>
+ %2 = cir.load %1 : !cir.ptr<!s64i, target_address_space(5)>, !s64i
+ cir.return %2 : !s64i
+ }
+
+ // CHECK: cir.func{{.*}} @kernel_field(%[[PTR:.*]]: !cir.ptr<!rec_Big, target_address_space(4)>
+ // CHECK-SAME: {llvm.align = 8 : i64, llvm.byref = !rec_Big, llvm.noundef})
+ // CHECK: %[[SLOT:.*]] = cir.alloca "arg0" align(8) init : !cir.ptr<!rec_Big, target_address_space(5)>
+ // CHECK-NOT: cir.store
+ // CHECK: cir.copy %[[PTR]] align(8) to %[[SLOT]] align(8)
+ // CHECK-SAME: : !cir.ptr<!rec_Big, target_address_space(4)>, !cir.ptr<!rec_Big, target_address_space(5)>
+ // CHECK: cir.get_member %[[SLOT]][0]
+
+ // A parameter the body never reads gets nothing at entry.
+ cir.func @kernel_unused(%arg0: !rec_Big) -> !s32i
+ attributes { test_classify = #byref_as4 } {
+ %r = cir.const #cir.int<0> : !s32i
+ cir.return %r : !s32i
+ }
+
+ // CHECK: cir.func{{.*}} @kernel_unused(%{{.*}}: !cir.ptr<!rec_Big, target_address_space(4)>
+ // CHECK-SAME: {llvm.align = 8 : i64, llvm.byref = !rec_Big, llvm.noundef})
+ // CHECK-NEXT: %{{.*}} = cir.const #cir.int<0> : !s32i
+
+ // A body that reads the value with no spill loads it at entry.
+ cir.func @kernel_uses_arg(%arg0: !rec_Big) -> !rec_Big
+ attributes { test_classify = #byref_as4 } {
+ cir.return %arg0 : !rec_Big
+ }
+
+ // CHECK: cir.func{{.*}} @kernel_uses_arg(%[[PTR:.*]]: !cir.ptr<!rec_Big, target_address_space(4)>
+ // CHECK: %[[V:.*]] = cir.load %[[PTR]] : !cir.ptr<!rec_Big, target_address_space(4)>, !rec_Big
+ // CHECK-NEXT: cir.return %[[V]] : !rec_Big
+
+ cir.func private @takes_big_as5(%arg0: !rec_Big)
+ attributes { test_classify = #byref_as5 }
+
+ // CHECK: cir.func{{.*}} @takes_big_as5(!cir.ptr<!rec_Big, target_address_space(5)>
+ // CHECK-SAME: {llvm.align = 8 : i64, llvm.byref = !rec_Big, llvm.noundef})
+
+ // Storage in the parameter's own address space is handed on.
+ cir.func @caller_forward(%s: !rec_Big)
+ attributes { test_classify = #passthrough } {
+ %tmp = cir.alloca "agg.tmp" align(8)
+ : !cir.ptr<!rec_Big, target_address_space(5)>
+ cir.store %s, %tmp : !rec_Big, !cir.ptr<!rec_Big, target_address_space(5)>
+ %v = cir.load %tmp : !cir.ptr<!rec_Big, target_address_space(5)>, !rec_Big
+ cir.call @takes_big_as5(%v) : (!rec_Big) -> ()
+ cir.return
+ }
+
+ // CHECK: cir.func{{.*}} @caller_forward
+ // CHECK: %[[TMP:.*]] = cir.alloca "agg.tmp" align(8) : !cir.ptr<!rec_Big, target_address_space(5)>
+ // CHECK-NOT: cir.alloca "byref"
+ // CHECK-NOT: cir.load
+ // CHECK: cir.call @takes_big_as5(%[[TMP]]) : (!cir.ptr<!rec_Big, target_address_space(5)>
+ // CHECK-SAME: {llvm.align = 8 : i64, llvm.byref = !rec_Big, llvm.noundef})
+
+ // An operand that names no storage is stored into a slot in the alloca
+ // address space.
+ cir.func @caller_no_storage(%s: !rec_Big)
+ attributes { test_classify = #passthrough } {
+ cir.call @takes_big_as5(%s) : (!rec_Big) -> ()
+ cir.return
+ }
+
+ // CHECK: cir.func{{.*}} @caller_no_storage(%[[S:.*]]: !rec_Big)
+ // CHECK: %[[SLOT:.*]] = cir.alloca "byref" align(8) : !cir.ptr<!rec_Big, target_address_space(5)>
+ // CHECK-NEXT: cir.store %[[S]], %[[SLOT]] : !rec_Big, !cir.ptr<!rec_Big, target_address_space(5)>
+ // CHECK-NEXT: cir.call @takes_big_as5(%[[SLOT]])
+
+ // A store between the load and the call stops the storage from being handed
+ // on, so the copy is taken where the load was.
+ cir.func @caller_store_between(%s: !rec_Big, %t: !rec_Big)
+ attributes { test_classify = #passthrough } {
+ %tmp = cir.alloca "agg.tmp" align(8)
+ : !cir.ptr<!rec_Big, target_address_space(5)>
+ cir.store %s, %tmp : !rec_Big, !cir.ptr<!rec_Big, target_address_space(5)>
+ %v = cir.load %tmp : !cir.ptr<!rec_Big, target_address_space(5)>, !rec_Big
+ cir.store %t, %tmp : !rec_Big, !cir.ptr<!rec_Big, target_address_space(5)>
+ cir.call @takes_big_as5(%v) : (!rec_Big) -> ()
+ cir.return
+ }
+
+ // CHECK: cir.func{{.*}} @caller_store_between(%[[S:[^:]+]]: !rec_Big, %[[T:[^:]+]]: !rec_Big)
+ // CHECK: %[[TMP:.*]] = cir.alloca "agg.tmp" align(8) : !cir.ptr<!rec_Big, target_address_space(5)>
+ // CHECK-NEXT: cir.store %[[S]], %[[TMP]]
+ // CHECK-NEXT: %[[SLOT:.*]] = cir.alloca "byref" align(8) : !cir.ptr<!rec_Big, target_address_space(5)>
+ // CHECK-NEXT: cir.copy %[[TMP]] align(8) to %[[SLOT]] align(8)
+ // CHECK-NEXT: cir.store %[[T]], %[[TMP]]
+ // CHECK-NEXT: cir.call @takes_big_as5(%[[SLOT]])
+
+}
+
+// -----
+
+// byref in the default address space with no alloca address space set.
+
+!s64i = !cir.int<s, 64>
+!rec_Big = !cir.struct<"Big" {data !s64i, data !s64i, data !s64i, data !s64i}>
+
+#byref_as0 = {
+ return = { kind = "direct" },
+ args = [ { kind = "indirect_aliased", indirect_align = 8 } ]
+}
+
+#passthrough = {
+ return = { kind = "direct" },
+ args = [ ]
+}
+
+module attributes {
+ dlti.dl_spec = #dlti.dl_spec<
+ #dlti.dl_entry<i64, dense<64>: vector<2xi64>>>
+} {
+
+ cir.func private @takes_big(%arg0: !rec_Big)
+ attributes { test_classify = #byref_as0 }
+
+ // CHECK: cir.func{{.*}} @takes_big(!cir.ptr<!rec_Big>
+ // CHECK-SAME: {llvm.align = 8 : i64, llvm.byref = !rec_Big, llvm.noundef})
+
+ cir.func @caller_forward(%s: !rec_Big)
+ attributes { test_classify = #passthrough } {
+ %tmp = cir.alloca "agg.tmp" align(8) : !cir.ptr<!rec_Big>
+ cir.store %s, %tmp : !rec_Big, !cir.ptr<!rec_Big>
+ %v = cir.load %tmp : !cir.ptr<!rec_Big>, !rec_Big
+ cir.call @takes_big(%v) : (!rec_Big) -> ()
+ cir.return
+ }
+
+ // CHECK: cir.func{{.*}} @caller_forward
+ // CHECK: %[[TMP:.*]] = cir.alloca "agg.tmp" align(8) : !cir.ptr<!rec_Big>
+ // CHECK-NOT: cir.load
+ // CHECK: cir.call @takes_big(%[[TMP]]) : (!cir.ptr<!rec_Big>
+
+ // Storage aligned below what the callee expects gets a slot of its own.
+ cir.func @caller_underaligned(%s: !rec_Big)
+ attributes { test_classify = #passthrough } {
+ %tmp = cir.alloca "agg.tmp" align(1) : !cir.ptr<!rec_Big>
+ cir.store %s, %tmp : !rec_Big, !cir.ptr<!rec_Big>
+ %v = cir.load align(1) %tmp : !cir.ptr<!rec_Big>, !rec_Big
+ cir.call @takes_big(%v) : (!rec_Big) -> ()
+ cir.return
+ }
+
+ // CHECK: cir.func{{.*}} @caller_underaligned
+ // CHECK: %[[TMP:.*]] = cir.alloca "agg.tmp" align(1) : !cir.ptr<!rec_Big>
+ // CHECK: %[[SLOT:.*]] = cir.alloca "byref" align(8) : !cir.ptr<!rec_Big>
+ // CHECK-NEXT: cir.copy %[[TMP]] align(1) to %[[SLOT]] align(8) : !cir.ptr<!rec_Big>
+ // CHECK-NEXT: cir.call @takes_big(%[[SLOT]])
+
+}
diff --git a/mlir/include/mlir/ABI/ABIRewriteContext.h b/mlir/include/mlir/ABI/ABIRewriteContext.h
index 555561979c15a8..9c8d5f3f6e3466 100644
--- a/mlir/include/mlir/ABI/ABIRewriteContext.h
+++ b/mlir/include/mlir/ABI/ABIRewriteContext.h
@@ -48,6 +48,10 @@ enum class ArgKind : uint8_t {
/// Pass indirectly via a pointer (sret for returns, byval for args).
Indirect,
+ /// Pass a pointer to the caller's object with no copy implied (byref). The
+ /// callee must not write through it. Arguments only.
+ IndirectAliased,
+
/// Ignore (void return, empty struct).
Ignore,
@@ -64,7 +68,7 @@ struct ArgClassification {
/// use the original type.
Type coercedType = nullptr;
- /// For Indirect: alignment of the pointed-to object.
+ /// For Indirect and IndirectAliased: alignment of the pointed-to object.
llvm::Align indirectAlign = llvm::Align(1);
/// For Extend: whether to sign-extend (true) or zero-extend (false).
@@ -77,8 +81,8 @@ struct ArgClassification {
/// For Indirect: whether the callee gets ownership (byval).
bool byVal = false;
- /// For Indirect: target address space of the pointer passed in place of
- /// the value. Zero is the default address space.
+ /// For Indirect and IndirectAliased: target address space of the pointer
+ /// passed in place of the value. Zero is the default address space.
unsigned indirectAddrSpace = 0;
/// For Direct with coercion: the byte offset within the original aggregate
@@ -143,6 +147,15 @@ struct ArgClassification {
return c;
}
+ static ArgClassification getIndirectAliased(llvm::Align align,
+ unsigned addrSpace) {
+ ArgClassification c;
+ c.kind = ArgKind::IndirectAliased;
+ c.indirectAlign = align;
+ c.indirectAddrSpace = addrSpace;
+ return c;
+ }
+
static ArgClassification getExtend(Type coerced, bool signExt) {
ArgClassification c;
c.kind = ArgKind::Extend;
diff --git a/mlir/include/mlir/ABI/Targets/Test/TestTarget.h b/mlir/include/mlir/ABI/Targets/Test/TestTarget.h
index 2036837b7d91a6..f1e637fc1f1c6b 100644
--- a/mlir/include/mlir/ABI/Targets/Test/TestTarget.h
+++ b/mlir/include/mlir/ABI/Targets/Test/TestTarget.h
@@ -59,7 +59,7 @@ FunctionClassification classify(TypeRange argTypes, Type returnType,
///
/// Per-arg/return dictionary keys:
/// kind: StringAttr. One of "direct", "extend", "indirect",
-/// "ignore", "expand".
+/// "indirect_aliased", "ignore", "expand".
///
/// For kind = "direct" (all optional):
/// coerced_type: TypeAttr. ABI-coerced type, if different from the
@@ -78,6 +78,9 @@ FunctionClassification classify(TypeRange argTypes, Type returnType,
/// indirect_addr_space: IntegerAttr. Target address space of the
/// pointer. Defaults to 0.
///
+/// For kind = "indirect_aliased": the same keys as "indirect" except byval,
+/// which it rejects.
+///
/// For kind = "ignore" / "expand": no extra keys.
///
/// Future schema additions tracked in projects/daily_log.md (Step 0c
diff --git a/mlir/lib/ABI/Targets/Test/TestTarget.cpp b/mlir/lib/ABI/Targets/Test/TestTarget.cpp
index 7af383efbf5172..4942397b046a8d 100644
--- a/mlir/lib/ABI/Targets/Test/TestTarget.cpp
+++ b/mlir/lib/ABI/Targets/Test/TestTarget.cpp
@@ -179,10 +179,11 @@ parseOne(DictionaryAttr argDict, function_ref<InFlightDiagnostic()> emitError) {
return ArgClassification::getExtend(coerced.getValue(), signExt);
}
- if (kind == "indirect") {
+ if (kind == "indirect" || kind == "indirect_aliased") {
auto align = argDict.getAs<IntegerAttr>("indirect_align");
if (!align) {
- emitError() << "kind='indirect' requires 'indirect_align' IntegerAttr";
+ emitError() << "kind='" << kind
+ << "' requires 'indirect_align' IntegerAttr";
return std::nullopt;
}
if (align.getInt() <= 0 || !llvm::isPowerOf2_64(align.getInt())) {
@@ -190,9 +191,6 @@ parseOne(DictionaryAttr argDict, function_ref<InFlightDiagnostic()> emitError) {
<< align.getInt();
return std::nullopt;
}
- bool byVal = true;
- if (auto bv = argDict.getAs<BoolAttr>("byval"))
- byVal = bv.getValue();
unsigned addrSpace = 0;
if (auto as = argDict.getAs<IntegerAttr>("indirect_addr_space")) {
if (as.getInt() < 0) {
@@ -202,6 +200,17 @@ parseOne(DictionaryAttr argDict, function_ref<InFlightDiagnostic()> emitError) {
}
addrSpace = as.getInt();
}
+ if (kind == "indirect_aliased") {
+ if (argDict.get("byval")) {
+ emitError() << "kind='indirect_aliased' does not take 'byval'";
+ return std::nullopt;
+ }
+ return ArgClassification::getIndirectAliased(llvm::Align(align.getInt()),
+ addrSpace);
+ }
+ bool byVal = true;
+ if (auto bv = argDict.getAs<BoolAttr>("byval"))
+ byVal = bv.getValue();
return ArgClassification::getIndirect(llvm::Align(align.getInt()), byVal,
addrSpace);
}
@@ -217,7 +226,8 @@ parseOne(DictionaryAttr argDict, function_ref<InFlightDiagnostic()> emitError) {
}
emitError() << "unknown kind='" << kind
- << "'; expected one of direct, extend, indirect, ignore, expand";
+ << "'; expected one of direct, extend, indirect, "
+ "indirect_aliased, ignore, expand";
return std::nullopt;
}
diff --git a/mlir/unittests/ABI/ABIRewriteContextTest.cpp b/mlir/unittests/ABI/ABIRewriteContextTest.cpp
index 3d3fcbed31fdc5..c79ac6a2b53bda 100644
--- a/mlir/unittests/ABI/ABIRewriteContextTest.cpp
+++ b/mlir/unittests/ABI/ABIRewriteContextTest.cpp
@@ -77,6 +77,16 @@ TEST(ABIRewriteContextTest, ArgClassificationIndirectAddrSpace) {
EXPECT_FALSE(c == ArgClassification::getIndirect(llvm::Align(8), true, 0));
}
+TEST(ABIRewriteContextTest, ArgClassificationIndirectAliased) {
+ auto c = ArgClassification::getIndirectAliased(llvm::Align(8), 4);
+ EXPECT_EQ(c.kind, ArgKind::IndirectAliased);
+ EXPECT_EQ(c.indirectAlign, llvm::Align(8));
+ EXPECT_EQ(c.indirectAddrSpace, 4u);
+ EXPECT_FALSE(c.byVal);
+ EXPECT_FALSE(c.isPassThrough());
+ EXPECT_FALSE(c == ArgClassification::getIndirect(llvm::Align(8), false, 4));
+}
+
TEST(ABIRewriteContextTest, ArgClassificationExtend) {
MLIRContext mlirCtx;
auto i8 = IntegerType::get(&mlirCtx, 8);
diff --git a/mlir/unittests/ABI/TestTargetTest.cpp b/mlir/unittests/ABI/TestTargetTest.cpp
index c1438dd834a3c3..5fd77f09455084 100644
--- a/mlir/unittests/ABI/TestTargetTest.cpp
+++ b/mlir/unittests/ABI/TestTargetTest.cpp
@@ -220,6 +220,54 @@ TEST_F(TestTargetParseTest, ParsesIndirectAddrSpace) {
EXPECT_EQ(fc.returnInfo.indirectAddrSpace, 5u);
}
+TEST_F(TestTargetParseTest, ParsesIndirectAliased) {
+ auto direct =
+ makeArg({builder.getNamedAttr("kind", builder.getStringAttr("direct"))});
+ auto aliased = makeArg({
+ builder.getNamedAttr("kind", builder.getStringAttr("indirect_aliased")),
+ builder.getNamedAttr("indirect_align", builder.getI64IntegerAttr(8)),
+ builder.getNamedAttr("indirect_addr_space", builder.getI64IntegerAttr(4)),
+ });
+ auto attr = builder.getDictionaryAttr({
+ builder.getNamedAttr("return", direct),
+ builder.getNamedAttr("args", builder.getArrayAttr({aliased})),
+ });
+
+ auto fc = parseOk(attr);
+ ASSERT_EQ(fc.argInfos.size(), 1u);
+ EXPECT_EQ(fc.argInfos[0].kind, ArgKind::IndirectAliased);
+ EXPECT_EQ(fc.argInfos[0].indirectAlign, llvm::Align(8));
+ EXPECT_EQ(fc.argInfos[0].indirectAddrSpace, 4u);
+ EXPECT_FALSE(fc.argInfos[0].byVal);
+}
+
+TEST_F(TestTargetParseTest, RejectsIndirectAliasedWithoutAlign) {
+ auto badAliased = makeArg({builder.getNamedAttr(
+ "kind", builder.getStringAttr("indirect_aliased"))});
+ auto direct =
+ makeArg({builder.getNamedAttr("kind", builder.getStringAttr("direct"))});
+ auto attr = builder.getDictionaryAttr({
+ builder.getNamedAttr("return", direct),
+ builder.getNamedAttr("args", builder.getArrayAttr({badAliased})),
+ });
+ parseError(attr, "kind='indirect_aliased' requires 'indirect_align'");
+}
+
+TEST_F(TestTargetParseTest, RejectsIndirectAliasedWithByval) {
+ auto badAliased = makeArg({
+ builder.getNamedAttr("kind", builder.getStringAttr("indirect_aliased")),
+ builder.getNamedAttr("indirect_align", builder.getI64IntegerAttr(8)),
+ builder.getNamedAttr("byval", builder.getBoolAttr(true)),
+ });
+ auto direct =
+ makeArg({builder.getNamedAttr("kind", builder.getStringAttr("direct"))});
+ auto attr = builder.getDictionaryAttr({
+ builder.getNamedAttr("return", direct),
+ builder.getNamedAttr("args", builder.getArrayAttr({badAliased})),
+ });
+ parseError(attr, "kind='indirect_aliased' does not take 'byval'");
+}
+
TEST_F(TestTargetParseTest, ParsesIgnoreAndExpand) {
auto ignore =
makeArg({builder.getNamedAttr("kind", builder.getStringAttr("ignore"))});
>From d9c999ab9d3ee9c69ef9c26588f54e20cae732ba Mon Sep 17 00:00:00 2001
From: skc7 <Krishna.Sankisa at amd.com>
Date: Wed, 21 Oct 2026 14:39:57 +0530
Subject: [PATCH 2/4] update CI failing test
---
clang/test/CIR/Transforms/abi-lowering/indirect-aliased.cir | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/clang/test/CIR/Transforms/abi-lowering/indirect-aliased.cir b/clang/test/CIR/Transforms/abi-lowering/indirect-aliased.cir
index f4e5ef30ee502f..5d5919bb808859 100644
--- a/clang/test/CIR/Transforms/abi-lowering/indirect-aliased.cir
+++ b/clang/test/CIR/Transforms/abi-lowering/indirect-aliased.cir
@@ -72,7 +72,7 @@ module attributes {
}
// CHECK: cir.func{{.*}} @kernel_uses_arg(%[[PTR:.*]]: !cir.ptr<!rec_Big, target_address_space(4)>
- // CHECK: %[[V:.*]] = cir.load %[[PTR]] : !cir.ptr<!rec_Big, target_address_space(4)>, !rec_Big
+ // CHECK: %[[V:.*]] = cir.load align(8) %[[PTR]] : !cir.ptr<!rec_Big, target_address_space(4)>, !rec_Big
// CHECK-NEXT: cir.return %[[V]] : !rec_Big
cir.func private @takes_big_as5(%arg0: !rec_Big)
>From 8f7abd750209c8deec1f64f8f33edaeb88dac38b Mon Sep 17 00:00:00 2001
From: skc7 <Krishna.Sankisa at amd.com>
Date: Thu, 22 Oct 2026 16:54:12 +0530
Subject: [PATCH 3/4] update nyi tests
---
.../Transforms/CallConvLoweringPass.cpp | 5 +-
.../Transforms/abi-lowering/amdgpu-byref.cir | 55 +++++++++++++++++++
.../abi-lowering/amdgpu-indirect-nyi.cir | 17 +-----
3 files changed, 58 insertions(+), 19 deletions(-)
create mode 100644 clang/test/CIR/Transforms/abi-lowering/amdgpu-byref.cir
diff --git a/clang/lib/CIR/Dialect/Transforms/CallConvLoweringPass.cpp b/clang/lib/CIR/Dialect/Transforms/CallConvLoweringPass.cpp
index 199824d55f4e06..e00362a0abd6ac 100644
--- a/clang/lib/CIR/Dialect/Transforms/CallConvLoweringPass.cpp
+++ b/clang/lib/CIR/Dialect/Transforms/CallConvLoweringPass.cpp
@@ -682,9 +682,8 @@ convertABIArgInfo(const llvm::abi::ArgInfo &info, MLIRContext *ctx,
mlir::Type extendedTy = abiTypeToCIR(info.getCoerceToType(), ctx);
return ArgClassification::getExtend(extendedTy, info.isSignExt());
}
- // ArgClassification has no address space for the indirect pointer yet.
- if (info.isIndirectAliased() ||
- (info.isIndirect() && info.getIndirectAddrSpace() != 0))
+ // The rewriter has no address space for the Indirect pointer yet.
+ if (info.isIndirect() && info.getIndirectAddrSpace() != 0)
return std::nullopt;
if (info.isIndirect())
return ArgClassification::getIndirect(info.getIndirectAlign(),
diff --git a/clang/test/CIR/Transforms/abi-lowering/amdgpu-byref.cir b/clang/test/CIR/Transforms/abi-lowering/amdgpu-byref.cir
new file mode 100644
index 00000000000000..b2b23a8c4158b1
--- /dev/null
+++ b/clang/test/CIR/Transforms/abi-lowering/amdgpu-byref.cir
@@ -0,0 +1,55 @@
+// RUN: cir-opt %s -cir-call-conv-lowering=target=amdgpu | FileCheck %s
+
+// AMDGPU byref (IndirectAliased) arguments under target=amdgpu. A multi-field
+// kernel struct is passed byref in addrspace(4). A device-function struct past
+// the 16-register budget is passed byref in addrspace(5).
+
+!s32i = !cir.int<s, 32>
+!rec_Pair = !cir.struct<"Pair" {data !s32i, data !s32i}>
+!rec_Big = !cir.struct<"Big" {data !cir.array<!s32i x 17>}>
+
+module attributes {
+ dlti.dl_spec = #dlti.dl_spec<
+ #dlti.dl_entry<i32, dense<32>: vector<2xi64>>,
+ #dlti.dl_entry<i64, dense<64>: vector<2xi64>>,
+ #dlti.dl_entry<"dlti.alloca_memory_space", 5 : ui64>>
+} {
+
+ // The CIRGen slot for a kernel argument is filled by a copy from addrspace(4).
+ cir.func @kern_pair(%arg0: !rec_Pair) -> !s32i cc(amdgpu_kernel) {
+ %0 = cir.alloca "p" align(4) init : !cir.ptr<!rec_Pair, target_address_space(5)>
+ cir.store %arg0, %0 : !rec_Pair, !cir.ptr<!rec_Pair, target_address_space(5)>
+ %1 = cir.get_member %0[1] {name = "b"}
+ : !cir.ptr<!rec_Pair, target_address_space(5)>
+ -> !cir.ptr<!s32i, target_address_space(5)>
+ %2 = cir.load %1 : !cir.ptr<!s32i, target_address_space(5)>, !s32i
+ cir.return %2 : !s32i
+ }
+
+ // CHECK: cir.func{{.*}} @kern_pair(%[[PTR:.*]]: !cir.ptr<!rec_Pair, target_address_space(4)> {llvm.align = 4 : i64, llvm.byref = !rec_Pair, llvm.noundef}) -> !s32i cc(amdgpu_kernel) {
+ // CHECK-NEXT: %[[SLOT:.*]] = cir.alloca "p" align(4) init : !cir.ptr<!rec_Pair, target_address_space(5)>
+ // CHECK-NEXT: cir.copy %[[PTR]] align(4) to %[[SLOT]] align(4) : !cir.ptr<!rec_Pair, target_address_space(4)>, !cir.ptr<!rec_Pair, target_address_space(5)>
+ // CHECK-NEXT: %[[B_PTR:.*]] = cir.get_member %[[SLOT]][1] {name = "b"} : !cir.ptr<!rec_Pair, target_address_space(5)> -> !cir.ptr<!s32i, target_address_space(5)>
+ // CHECK-NEXT: %[[B:.*]] = cir.load %[[B_PTR]] : !cir.ptr<!s32i, target_address_space(5)>, !s32i
+ // CHECK-NEXT: cir.return %[[B]] : !s32i
+
+ // A device-function argument past the register budget.
+ cir.func @take_big(%arg0: !rec_Big) {
+ cir.return
+ }
+
+ // CHECK: cir.func{{.*}} @take_big(%{{.*}}: !cir.ptr<!rec_Big, target_address_space(5)> {llvm.align = 4 : i64, llvm.byref = !rec_Big, llvm.noundef}) {
+
+ // The caller hands its own addrspace(5) storage to the callee.
+ cir.func @call_big() {
+ %0 = cir.alloca "b" align(4) : !cir.ptr<!rec_Big, target_address_space(5)>
+ %1 = cir.load %0 : !cir.ptr<!rec_Big, target_address_space(5)>, !rec_Big
+ cir.call @take_big(%1) : (!rec_Big) -> ()
+ cir.return
+ }
+
+ // CHECK: cir.func{{.*}} @call_big() {
+ // CHECK-NEXT: %[[B_SLOT:.*]] = cir.alloca "b" align(4) : !cir.ptr<!rec_Big, target_address_space(5)>
+ // CHECK-NEXT: cir.call @take_big(%[[B_SLOT]]) : (!cir.ptr<!rec_Big, target_address_space(5)> {llvm.align = 4 : i64, llvm.byref = !rec_Big, llvm.noundef}) -> ()
+ // CHECK-NEXT: cir.return
+}
diff --git a/clang/test/CIR/Transforms/abi-lowering/amdgpu-indirect-nyi.cir b/clang/test/CIR/Transforms/abi-lowering/amdgpu-indirect-nyi.cir
index c925f21bc5189e..00fdbe8bba5237 100644
--- a/clang/test/CIR/Transforms/abi-lowering/amdgpu-indirect-nyi.cir
+++ b/clang/test/CIR/Transforms/abi-lowering/amdgpu-indirect-nyi.cir
@@ -1,10 +1,9 @@
// RUN: not cir-opt %s -cir-call-conv-lowering=target=amdgpu 2>&1 | FileCheck %s
-// AMDGPU classifications whose indirect pointer is not in the default address
+// AMDGPU Indirect classifications whose pointer is not in the default address
// space are not lowered yet, so they are reported rather than misclassified.
!s32i = !cir.int<s, 32>
-!rec_Pair = !cir.struct<"Pair" {data !s32i, data !s32i}>
!rec_Big = !cir.struct<"Big" {data !cir.array<!s32i x 17>}>
module attributes {
@@ -13,20 +12,6 @@ module attributes {
#dlti.dl_entry<i64, dense<64>: vector<2xi64>>>
} {
- // A multi-field kernel argument is passed byref in addrspace(4).
- cir.func @kern_pair(%arg0: !rec_Pair) cc(amdgpu_kernel) {
- cir.return
- }
-
- // CHECK: not yet implemented for the ABI coercion of type '!cir.struct<"Pair"
-
- // An argument past the 16-register budget is passed byref in addrspace(5).
- cir.func @take_big(%arg0: !rec_Big) {
- cir.return
- }
-
- // CHECK: not yet implemented for the ABI coercion of type '!cir.struct<"Big"
-
// A return past the register budget goes through an sret in addrspace(5).
cir.func @ret_big(%arg0: !cir.ptr<!rec_Big>) -> !rec_Big {
%0 = cir.load %arg0 : !cir.ptr<!rec_Big>, !rec_Big
>From a6e45cca563e3df8fe58c926cedaeba408af9782 Mon Sep 17 00:00:00 2001
From: skc7 <Krishna.Sankisa at amd.com>
Date: Sat, 24 Oct 2026 10:51:05 +0530
Subject: [PATCH 4/4] update error
---
.../Dialect/Transforms/TargetLowering/CIRABIRewriteContext.cpp | 3 +--
.../test/CIR/Transforms/abi-lowering/indirect-aliased-nyi.cir | 3 +--
2 files changed, 2 insertions(+), 4 deletions(-)
diff --git a/clang/lib/CIR/Dialect/Transforms/TargetLowering/CIRABIRewriteContext.cpp b/clang/lib/CIR/Dialect/Transforms/TargetLowering/CIRABIRewriteContext.cpp
index cd290457f3565c..9850cbd092196e 100644
--- a/clang/lib/CIR/Dialect/Transforms/TargetLowering/CIRABIRewriteContext.cpp
+++ b/clang/lib/CIR/Dialect/Transforms/TargetLowering/CIRABIRewriteContext.cpp
@@ -185,8 +185,7 @@ computeNewReturnType(mlir::Type origRetTy, const ArgClassification &retInfo,
<< "it in EmitFunctionEpilog)";
return nullptr;
case ArgKind::IndirectAliased:
- emitError() << "IndirectAliased return is not allowed (classic codegen "
- << "rejects it in EmitFunctionEpilog)";
+ emitError() << "IndirectAliased return is not supported";
return nullptr;
case ArgKind::Extend:
// Same convention as Extend args: keep the original return type in the
diff --git a/clang/test/CIR/Transforms/abi-lowering/indirect-aliased-nyi.cir b/clang/test/CIR/Transforms/abi-lowering/indirect-aliased-nyi.cir
index adcb86f35eb51e..ddab1815735524 100644
--- a/clang/test/CIR/Transforms/abi-lowering/indirect-aliased-nyi.cir
+++ b/clang/test/CIR/Transforms/abi-lowering/indirect-aliased-nyi.cir
@@ -18,8 +18,7 @@ module attributes {
cir.func private @ret_big() -> !rec_Big
attributes { test_classify = #byref_return }
- // CHECK: error: 'cir.func' op IndirectAliased return is not allowed
- // CHECK-SAME: (classic codegen rejects it in EmitFunctionEpilog)
+ // CHECK: error: 'cir.func' op IndirectAliased return is not supported
}
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