[AIX][XCOFF] Supporting the ReadOnlyWithRel SectionKnd

SUMMARY:
In this patch we put the global variable in a Csect which's SectionKind is "ReadOnlyWithRel" into Data Section.

Reviewers: hubert.reinterpretcast,jasonliu,Xiangling_L
Subscribers: wuzish, nemanjai, hiraditya

Differential Revision: https://reviews.llvm.org/D72461

diff --git a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index 847825e..8cb9814 100644 (file)
--- a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -1870,7 +1870,10 @@ MCSection *TargetLoweringObjectFileXCOFF::SelectSectionForGlobal(
   if (Kind.isText())
     return TextSection;
 
-  if (Kind.isData())
+  if (Kind.isData() || Kind.isReadOnlyWithRel())
+    // TODO: We may put this under option control, because user may want to
+    // have read-only data with relocations placed into a read-only section by
+    // the compiler.
     return DataSection;
 
   // Zero initialized data must be emitted to the .data section because external

diff --git a/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp b/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
index f93f1c0..0458f5a 100644 (file)
--- a/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
+++ b/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
@@ -1636,8 +1636,7 @@ void PPCAIXAsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
       TargetLoweringObjectFileXCOFF::getStorageClassForGlobal(GV));
 
   SectionKind GVKind = getObjFileLowering().getKindForGlobal(GV, TM);
-  if ((!GVKind.isCommon() && !GVKind.isBSS() && !GVKind.isData() &&
-       !GVKind.isReadOnly()) ||
+  if ((!GVKind.isGlobalWriteableData() && !GVKind.isReadOnly()) ||
       GVKind.isMergeable2ByteCString() || GVKind.isMergeable4ByteCString())
     report_fatal_error("Encountered a global variable kind that is "
                        "not supported yet.");

diff --git a/llvm/test/CodeGen/PowerPC/aix-readonly-with-relocation.ll b/llvm/test/CodeGen/PowerPC/aix-readonly-with-relocation.ll
new file mode 100644 (file)
index 0000000..97b39f5
--- /dev/null
+++ b/llvm/test/CodeGen/PowerPC/aix-readonly-with-relocation.ll
@@ -0,0 +1,19 @@
+; RUN: llc -verify-machineinstrs -mcpu=pwr4 -mtriple powerpc-ibm-aix-xcoff --relocation-model=pic < %s | FileCheck %s
+; RUN: llc -verify-machineinstrs -mcpu=pwr4 -mtriple powerpc64-ibm-aix-xcoff --relocation-model=pic < %s | FileCheck --check-prefix=CHECK64 %s
+
+@a = common global i32 0
+@b = constant i32* @a
+
+;CHECK:         .comm   a[RW],4,2
+;CHECK-NEXT:    .csect .data[RW]
+;CHECK-NEXT:    .globl  b
+;CHECK-NEXT:    .align  2
+;CHECK-NEXT: b:
+;CHECK-NEXT:    .long   a
+
+;CHECK64:       .comm   a[RW],4,2
+;CHECK64-NEXT:  .csect .data[RW]
+;CHECK64-NEXT:  .globl  b
+;CHECK64-NEXT:  .align  3
+;CHECK64-NEXT: b:
+;CHECK64-NEXT:  .llong  a