Initial patch for x32 ABI support.

Add the x32 environment kind to the triple, and separate the concept of
pointer size and callee save stack slot size, since they're not equal
on x32.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173175 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 11 insertions, 3 deletions

diff --git a/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp b/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
index 16488eb..7815ae9 100644
--- a/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
+++ b/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
@@ -44,7 +44,7 @@ void X86MCAsmInfoDarwin::anchor() { }
 X86MCAsmInfoDarwin::X86MCAsmInfoDarwin(const Triple &T) {
   bool is64Bit = T.getArch() == Triple::x86_64;
   if (is64Bit)
-    PointerSize = 8;
+    PointerSize = CalleeSaveStackSlotSize = 8;
 
   AssemblerDialect = AsmWriterFlavor;
 
@@ -76,8 +76,16 @@ X86_64MCAsmInfoDarwin::X86_64MCAsmInfoDarwin(const Triple &Triple)
 void X86ELFMCAsmInfo::anchor() { }
 
 X86ELFMCAsmInfo::X86ELFMCAsmInfo(const Triple &T) {
-  if (T.getArch() == Triple::x86_64)
-    PointerSize = 8;
+  bool is64Bit = T.getArch() == Triple::x86_64;
+  bool isX32 = T.getEnvironment() == Triple::GNUX32;
+
+  // For ELF, x86-64 pointer size depends on the ABI.
+  // For x86-64 without the x32 ABI, pointer size is 8. For x86 and for x86-64
+  // with the x32 ABI, pointer size remains the default 4.
+  PointerSize = (is64Bit && !isX32) ? 8 : 4;
+
+  // OTOH, stack slot size is always 8 for x86-64, even with the x32 ABI.
+  CalleeSaveStackSlotSize = is64Bit ? 8 : 4;
 
   AssemblerDialect = AsmWriterFlavor;