Author: Andy Kaylor Date: 2025-05-21T09:14:48-07:00 New Revision: fc9898c4c09fa4e5b83f99d36e847769bf60da60
URL: https://github.com/llvm/llvm-project/commit/fc9898c4c09fa4e5b83f99d36e847769bf60da60 DIFF: https://github.com/llvm/llvm-project/commit/fc9898c4c09fa4e5b83f99d36e847769bf60da60.diff LOG: [CIR] Add support for recursive record layouts (#140811) While processing members of a record, we try to create new record types as we encounter them, but if this would result in recursion (either because the type points to itself or because it points to a type that points back to the original type) we need to add it to a list for deferred processing. Previously, we issued an error saying this wasn't handled. This change adds the necessary handling. Added: Modified: clang/include/clang/CIR/MissingFeatures.h clang/lib/CIR/CodeGen/CIRGenTypes.cpp clang/lib/CIR/CodeGen/CIRGenTypes.h clang/test/CIR/CodeGen/struct.c Removed: ################################################################################ diff --git a/clang/include/clang/CIR/MissingFeatures.h b/clang/include/clang/CIR/MissingFeatures.h index 7b33d94483d5f..3c21b8c629422 100644 --- a/clang/include/clang/CIR/MissingFeatures.h +++ b/clang/include/clang/CIR/MissingFeatures.h @@ -127,7 +127,6 @@ struct MissingFeatures { static bool shouldReverseUnaryCondOnBoolExpr() { return false; } // RecordType - static bool recursiveRecordLayout() { return false; } static bool skippedLayout() { return false; } static bool astRecordDeclAttr() { return false; } static bool cxxSupport() { return false; } diff --git a/clang/lib/CIR/CodeGen/CIRGenTypes.cpp b/clang/lib/CIR/CodeGen/CIRGenTypes.cpp index 77f00a8e98ca8..0665ea0506875 100644 --- a/clang/lib/CIR/CodeGen/CIRGenTypes.cpp +++ b/clang/lib/CIR/CodeGen/CIRGenTypes.cpp @@ -226,7 +226,7 @@ mlir::Type CIRGenTypes::convertRecordDeclType(const clang::RecordDecl *rd) { // If converting this type would cause us to infinitely loop, don't do it! if (!isSafeToConvert(rd, *this)) { - cgm.errorNYI(rd->getSourceRange(), "recursive record layout"); + deferredRecords.push_back(rd); return entry; } @@ -259,7 +259,9 @@ mlir::Type CIRGenTypes::convertRecordDeclType(const clang::RecordDecl *rd) { // If we're done converting the outer-most record, then convert any deferred // records as well. - assert(!cir::MissingFeatures::recursiveRecordLayout()); + if (recordsBeingLaidOut.empty()) + while (!deferredRecords.empty()) + convertRecordDeclType(deferredRecords.pop_back_val()); return entry; } diff --git a/clang/lib/CIR/CodeGen/CIRGenTypes.h b/clang/lib/CIR/CodeGen/CIRGenTypes.h index a0f546d0a7cd6..7a4301ed38d04 100644 --- a/clang/lib/CIR/CodeGen/CIRGenTypes.h +++ b/clang/lib/CIR/CodeGen/CIRGenTypes.h @@ -68,6 +68,8 @@ class CIRGenTypes { /// types will be in this set. llvm::SmallPtrSet<const clang::Type *, 4> recordsBeingLaidOut; + llvm::SmallVector<const clang::RecordDecl *, 8> deferredRecords; + /// Heper for convertType. mlir::Type convertFunctionTypeInternal(clang::QualType ft); diff --git a/clang/test/CIR/CodeGen/struct.c b/clang/test/CIR/CodeGen/struct.c index c91a14e0637c1..725b56a068488 100644 --- a/clang/test/CIR/CodeGen/struct.c +++ b/clang/test/CIR/CodeGen/struct.c @@ -13,16 +13,34 @@ // CIR-DAG: !rec_InnerS = !cir.record<struct "InnerS" {!s32i, !s8i}> // CIR-DAG: !rec_PackedS = !cir.record<struct "PackedS" packed {!s32i, !s8i}> // CIR-DAG: !rec_PackedAndPaddedS = !cir.record<struct "PackedAndPaddedS" packed padded {!s32i, !s8i, !u8i}> +// CIR-DAG: !rec_NodeS = !cir.record<struct "NodeS" {!cir.ptr<!cir.record<struct "NodeS">>}> +// CIR-DAG: !rec_RightS = !cir.record<struct "RightS" {!cir.ptr<!cir.record<struct "LeftS" {!cir.ptr<!cir.record<struct "RightS">>}>>}> +// CIR-DAG: !rec_LeftS = !cir.record<struct "LeftS" {!cir.ptr<!rec_RightS>}> +// CIR-DAG: !rec_CycleEnd = !cir.record<struct "CycleEnd" {!cir.ptr<!cir.record<struct "CycleStart" {!cir.ptr<!cir.record<struct "CycleMiddle" {!cir.ptr<!cir.record<struct "CycleEnd">>}>>}>>}> +// CIR-DAG: !rec_CycleMiddle = !cir.record<struct "CycleMiddle" {!cir.ptr<!rec_CycleEnd>}> +// CIR-DAG: !rec_CycleStart = !cir.record<struct "CycleStart" {!cir.ptr<!rec_CycleMiddle>}> // LLVM-DAG: %struct.CompleteS = type { i32, i8 } // LLVM-DAG: %struct.OuterS = type { %struct.InnerS, i32 } // LLVM-DAG: %struct.InnerS = type { i32, i8 } // LLVM-DAG: %struct.PackedS = type <{ i32, i8 }> // LLVM-DAG: %struct.PackedAndPaddedS = type <{ i32, i8, i8 }> +// LLVM-DAG: %struct.NodeS = type { ptr } +// LLVM-DAG: %struct.LeftS = type { ptr } +// LLVM-DAG: %struct.RightS = type { ptr } +// LLVM-DAG: %struct.CycleStart = type { ptr } +// LLVM-DAG: %struct.CycleMiddle = type { ptr } +// LLVM-DAG: %struct.CycleEnd = type { ptr } // OGCG-DAG: %struct.CompleteS = type { i32, i8 } // OGCG-DAG: %struct.OuterS = type { %struct.InnerS, i32 } // OGCG-DAG: %struct.InnerS = type { i32, i8 } // OGCG-DAG: %struct.PackedS = type <{ i32, i8 }> // OGCG-DAG: %struct.PackedAndPaddedS = type <{ i32, i8, i8 }> +// OGCG-DAG: %struct.NodeS = type { ptr } +// OGCG-DAG: %struct.LeftS = type { ptr } +// OGCG-DAG: %struct.RightS = type { ptr } +// OGCG-DAG: %struct.CycleStart = type { ptr } +// OGCG-DAG: %struct.CycleMiddle = type { ptr } +// OGCG-DAG: %struct.CycleEnd = type { ptr } struct IncompleteS *p; @@ -78,6 +96,59 @@ struct PackedAndPaddedS { #pragma pack(pop) +// Recursive type +struct NodeS { + struct NodeS* next; +} node; + +// CIR: cir.global{{.*}} @node = #cir.zero : !rec_NodeS +// LLVM-DAG: @node = dso_local global %struct.NodeS zeroinitializer +// OGCG-DAG: @node = global %struct.NodeS zeroinitializer + +// Mutually dependent types +struct RightS; +struct LeftS { + struct RightS* right; +} ls; + +// CIR: cir.global{{.*}} @ls = #cir.zero : !rec_LeftS +// LLVM-DAG: @ls = dso_local global %struct.LeftS zeroinitializer +// OGCG-DAG: @ls = global %struct.LeftS zeroinitializer + +struct RightS { + struct LeftS* left; +} rs; + +// CIR: cir.global{{.*}} @rs = #cir.zero : !rec_RightS +// LLVM-DAG: @rs = dso_local global %struct.RightS zeroinitializer +// OGCG-DAG: @rs = global %struct.RightS zeroinitializer + +struct CycleMiddle; +struct CycleEnd; +struct CycleStart { + struct CycleMiddle* middle; +} start; + +// CIR: cir.global{{.*}} @start = #cir.zero : !rec_CycleStart +// LLVM-DAG: @start = dso_local global %struct.CycleStart zeroinitializer +// OGCG-DAG: @start = global %struct.CycleStart zeroinitializer + +struct CycleMiddle { + struct CycleEnd* end; +} middle; + +// CIR: cir.global{{.*}} @middle = #cir.zero : !rec_CycleMiddle +// LLVM-DAG: @middle = dso_local global %struct.CycleMiddle zeroinitializer +// OGCG-DAG: @middle = global %struct.CycleMiddle zeroinitializer + +struct CycleEnd { + struct CycleStart* start; +} end; + +// CIR: cir.global{{.*}} @end = #cir.zero : !rec_CycleEnd +// LLVM-DAG: @end = dso_local global %struct.CycleEnd zeroinitializer +// OGCG-DAG: @end = global %struct.CycleEnd zeroinitializer + void f(void) { struct IncompleteS *p; } @@ -205,3 +276,40 @@ char f4(int a, struct CompleteS *p) { // OGCG-NEXT: %[[P_B:.*]] = getelementptr inbounds nuw %struct.CompleteS, ptr %[[P2]], i32 0, i32 1 // OGCG-NEXT: %[[P_B_VAL:.*]] = load i8, ptr %[[P_B]], align 4 // OGCG-NEXT: ret i8 %[[P_B_VAL]] + +void f5(struct NodeS* a) { + a->next = 0; +} + +// CIR: cir.func @f5 +// CIR: %[[NEXT:.*]] = cir.get_member {{%.}}[0] {name = "next"} : !cir.ptr<!rec_NodeS> -> !cir.ptr<!cir.ptr<!rec_NodeS>> +// CIR: cir.store {{.*}}, %[[NEXT]] + +// LLVM: define{{.*}} void @f5 +// LLVM: %[[NEXT:.*]] = getelementptr %struct.NodeS, ptr %{{.*}}, i32 0, i32 0 +// LLVM: store ptr null, ptr %[[NEXT]] + +// OGCG: define{{.*}} void @f5 +// OGCG: %[[NEXT:.*]] = getelementptr inbounds nuw %struct.NodeS, ptr %{{.*}}, i32 0, i32 0 +// OGCG: store ptr null, ptr %[[NEXT]] + +void f6(struct CycleStart *start) { + struct CycleMiddle *middle = start->middle; + struct CycleEnd *end = middle->end; + struct CycleStart *start2 = end->start; +} + +// CIR: cir.func @f6 +// CIR: %[[MIDDLE:.*]] = cir.get_member {{.*}}[0] {name = "middle"} : !cir.ptr<!rec_CycleStart> -> !cir.ptr<!cir.ptr<!rec_CycleMiddle>> +// CIR: %[[END:.*]] = cir.get_member %{{.*}}[0] {name = "end"} : !cir.ptr<!rec_CycleMiddle> -> !cir.ptr<!cir.ptr<!rec_CycleEnd>> +// CIR: %[[START2:.*]] = cir.get_member %{{.*}}[0] {name = "start"} : !cir.ptr<!rec_CycleEnd> -> !cir.ptr<!cir.ptr<!rec_CycleStart>> + +// LLVM: define{{.*}} void @f6 +// LLVM: %[[MIDDLE:.*]] = getelementptr %struct.CycleStart, ptr %{{.*}}, i32 0, i32 0 +// LLVM: %[[END:.*]] = getelementptr %struct.CycleMiddle, ptr %{{.*}}, i32 0, i32 0 +// LLVM: %[[START2:.*]] = getelementptr %struct.CycleEnd, ptr %{{.*}}, i32 0, i32 0 + +// OGCG: define{{.*}} void @f6 +// OGCG: %[[MIDDLE:.*]] = getelementptr inbounds nuw %struct.CycleStart, ptr %{{.*}}, i32 0, i32 0 +// OGCG: %[[END:.*]] = getelementptr inbounds nuw %struct.CycleMiddle, ptr %{{.*}}, i32 0, i32 0 +// OGCG: %[[START2:.*]] = getelementptr inbounds nuw %struct.CycleEnd, ptr %{{.*}}, i32 0, i32 0 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
