[AIX] Handle ReadOnlyWithRel kind on AIX.

Summary: This patch handles the SectionKind of ReadOnlyWithRel on AIX. The failure was discovered during sanitizer enablement and occured with `-fsanitize-coverage` option.

Reviewed By: hubert.reinterpretcast

Differential Revision: https://reviews.llvm.org/D157483

Author: esmeyi

llvm/lib/MC/MCSectionXCOFF.cpp

@@ -42,6 +42,16 @@ void MCSectionXCOFF::printSwitchToSection(const MCAsmInfo &MAI, const Triple &T,
     return;
   }
 
+  if (getKind().isReadOnlyWithRel()) {
+    if (getMappingClass() != XCOFF::XMC_RW &&
+        getMappingClass() != XCOFF::XMC_RO &&
+        getMappingClass() != XCOFF::XMC_TD)
+      report_fatal_error(
+          "Unexepected storage-mapping class for ReadOnlyWithRel kind");
+    printCsectDirective(OS);
+    return;
+  }
+
   // Initialized TLS data.
   if (getKind().isThreadData()) {
     // We only expect XMC_TL here for initialized TLS data.
@@ -72,8 +82,7 @@ void MCSectionXCOFF::printSwitchToSection(const MCAsmInfo &MAI, const Triple &T,
   }
 
   if (isCsect() && getMappingClass() == XCOFF::XMC_TD) {
-    assert((getKind().isBSSExtern() || getKind().isBSSLocal() ||
-            getKind().isReadOnlyWithRel()) &&
+    assert((getKind().isBSSExtern() || getKind().isBSSLocal()) &&
            "Unexepected section kind for toc-data");
     printCsectDirective(OS);
     return;

llvm/test/CodeGen/PowerPC/aix-relro-section.ll

@@ -0,0 +1,105 @@
+; RUN: llc -mtriple powerpc-ibm-aix-xcoff < %s | FileCheck %s --check-prefix CHECK
+; RUN: llc -mtriple powerpc64-ibm-aix-xcoff < %s | FileCheck %s --check-prefix CHECK
+; RUN: llc -mtriple powerpc-ibm-aix-xcoff -mxcoff-roptr < %s | FileCheck %s --check-prefix CHECK-RO
+; RUN: llc -mtriple powerpc64-ibm-aix-xcoff -mxcoff-roptr < %s | FileCheck %s --check-prefix CHECK-RO
+
+; RUN: llc -filetype=obj -mtriple powerpc-ibm-aix-xcoff -verify-machineinstrs < %s -o %t32.o
+; RUN: llvm-readobj %t32.o --syms --relocs | FileCheck %s --check-prefix=OBJ32
+
+; RUN: llc -filetype=obj -mtriple powerpc64-ibm-aix-xcoff -verify-machineinstrs < %s -o %t64.o
+; RUN: llvm-readobj %t64.o --syms --relocs | FileCheck %s --check-prefix=OBJ64
+
+@var = external constant i32
+@ptr = private constant ptr @var, section "relro-section"
+
+; CHECK: .extern var[UA]
+; CHECK: .csect _Renamed..2drelro_section[RW]
+
+; CHECK-RO: .extern var[UA]
+; CHECK-RO: .csect _Renamed..2drelro_section[RO]
+
+; OBJ32:      Relocations [
+; OBJ32-NEXT:   Section (index: 2) .data {
+; OBJ32-NEXT:     0x0 R_POS var(1) 0x1F
+; OBJ32-NEXT:   }
+; OBJ32-NEXT: ]
+; OBJ32-NEXT: Symbols [
+; OBJ32:          Index: 1
+; OBJ32-NEXT:     Name: var
+; OBJ32-NEXT:     Value (RelocatableAddress): 0x0
+; OBJ32-NEXT:     Section: N_UNDEF
+; OBJ32-NEXT:     Type: 0x0
+; OBJ32-NEXT:     StorageClass: C_EXT (0x2)
+; OBJ32-NEXT:     NumberOfAuxEntries: 1
+; OBJ32-NEXT:     CSECT Auxiliary Entry {
+; OBJ32-NEXT:       Index: 2
+; OBJ32-NEXT:       SectionLen: 0
+; OBJ32-NEXT:       ParameterHashIndex: 0x0
+; OBJ32-NEXT:       TypeChkSectNum: 0x0
+; OBJ32-NEXT:       SymbolAlignmentLog2: 0
+; OBJ32-NEXT:       SymbolType: XTY_ER (0x0)
+; OBJ32-NEXT:       StorageMappingClass: XMC_UA (0x4)
+; OBJ32-NEXT:       StabInfoIndex: 0x0
+; OBJ32-NEXT:       StabSectNum: 0x0
+; OBJ32-NEXT:     }
+; OBJ32:          Index: 5
+; OBJ32-NEXT:     Name: relro-section
+; OBJ32-NEXT:     Value (RelocatableAddress): 0x0
+; OBJ32-NEXT:     Section: .data
+; OBJ32-NEXT:     Type: 0x0
+; OBJ32-NEXT:     StorageClass: C_HIDEXT (0x6B)
+; OBJ32-NEXT:     NumberOfAuxEntries: 1
+; OBJ32-NEXT:     CSECT Auxiliary Entry {
+; OBJ32-NEXT:       Index: 6
+; OBJ32-NEXT:       SectionLen: 4
+; OBJ32-NEXT:       ParameterHashIndex: 0x0
+; OBJ32-NEXT:       TypeChkSectNum: 0x0
+; OBJ32-NEXT:       SymbolAlignmentLog2: 2
+; OBJ32-NEXT:       SymbolType: XTY_SD (0x1)
+; OBJ32-NEXT:       StorageMappingClass: XMC_RW (0x5)
+; OBJ32-NEXT:       StabInfoIndex: 0x0
+; OBJ32-NEXT:       StabSectNum: 0x0
+; OBJ32-NEXT:     }
+; OBJ32:       ]
+
+; OBJ64:      Relocations [
+; OBJ64-NEXT:   Section (index: 2) .data {
+; OBJ64-NEXT:     0x0 R_POS var(1) 0x3F
+; OBJ64-NEXT:   }
+; OBJ64-NEXT: ]
+; OBJ64-NEXT: Symbols [
+; OBJ64:          Index: 1
+; OBJ64-NEXT:     Name: var
+; OBJ64-NEXT:     Value (RelocatableAddress): 0x0
+; OBJ64-NEXT:     Section: N_UNDEF
+; OBJ64-NEXT:     Type: 0x0
+; OBJ64-NEXT:     StorageClass: C_EXT (0x2)
+; OBJ64-NEXT:     NumberOfAuxEntries: 1
+; OBJ64-NEXT:     CSECT Auxiliary Entry {
+; OBJ64-NEXT:       Index: 2
+; OBJ64-NEXT:       SectionLen: 0
+; OBJ64-NEXT:       ParameterHashIndex: 0x0
+; OBJ64-NEXT:       TypeChkSectNum: 0x0
+; OBJ64-NEXT:       SymbolAlignmentLog2: 0
+; OBJ64-NEXT:       SymbolType: XTY_ER (0x0)
+; OBJ64-NEXT:       StorageMappingClass: XMC_UA (0x4)
+; OBJ64-NEXT:       Auxiliary Type: AUX_CSECT (0xFB)
+; OBJ64-NEXT:     }
+; OBJ64:          Index: 5
+; OBJ64-NEXT:     Name: relro-section
+; OBJ64-NEXT:     Value (RelocatableAddress): 0x0
+; OBJ64-NEXT:     Section: .data
+; OBJ64-NEXT:     Type: 0x0
+; OBJ64-NEXT:     StorageClass: C_HIDEXT (0x6B)
+; OBJ64-NEXT:     NumberOfAuxEntries: 1
+; OBJ64-NEXT:     CSECT Auxiliary Entry {
+; OBJ64-NEXT:       Index: 6
+; OBJ64-NEXT:       SectionLen: 8
+; OBJ64-NEXT:       ParameterHashIndex: 0x0
+; OBJ64-NEXT:       TypeChkSectNum: 0x0
+; OBJ64-NEXT:       SymbolAlignmentLog2: 3
+; OBJ64-NEXT:       SymbolType: XTY_SD (0x1)
+; OBJ64-NEXT:       StorageMappingClass: XMC_RW (0x5)
+; OBJ64-NEXT:       Auxiliary Type: AUX_CSECT (0xFB)
+; OBJ64-NEXT:     }
+; OBJ64:      ]