Implement cfi_rel_offset

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129306 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/MC/MCParser/AsmParser.cpp b/lib/MC/MCParser/AsmParser.cpp
index 5eb772eafaac8edd18f18d7175520eb16b71fe71..8af4ac62e221c321cdffe472900cfbfa0b1185db 100644 (file)
--- a/lib/MC/MCParser/AsmParser.cpp
+++ b/lib/MC/MCParser/AsmParser.cpp
@@ -80,6 +80,10 @@ private:
   SourceMgr &SrcMgr;
   MCAsmParserExtension *GenericParser;
   MCAsmParserExtension *PlatformParser;
+
+  // FIXME: This is not the best place to store this. To handle a (for example)
+  // .cfi_rel_offset before a .cfi_def_cfa_offset we need to know the initial
+  // frame state.
   int64_t LastOffset;
 
   /// This is the current buffer index we're lexing from as managed by the
@@ -145,6 +149,9 @@ public:
     LastOffset += Adjustment;
     return LastOffset;
   }
+  int64_t getLastOffset() {
+    return LastOffset;
+  }
   void setLastOffset(int64_t Offset) {
     LastOffset = Offset;
   }
@@ -266,6 +273,8 @@ public:
                                                        ".cfi_def_cfa_register");
     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveCFIOffset>(
                                                                  ".cfi_offset");
+    AddDirectiveHandler<&GenericAsmParser::ParseDirectiveCFIRelOffset>(
+                                                             ".cfi_rel_offset");
     AddDirectiveHandler<
      &GenericAsmParser::ParseDirectiveCFIPersonalityOrLsda>(".cfi_personality");
     AddDirectiveHandler<
@@ -301,6 +310,7 @@ public:
   bool ParseDirectiveCFIAdjustCfaOffset(StringRef, SMLoc DirectiveLoc);
   bool ParseDirectiveCFIDefCfaRegister(StringRef, SMLoc DirectiveLoc);
   bool ParseDirectiveCFIOffset(StringRef, SMLoc DirectiveLoc);
+  bool ParseDirectiveCFIRelOffset(StringRef, SMLoc DirectiveLoc);
   bool ParseDirectiveCFIPersonalityOrLsda(StringRef, SMLoc DirectiveLoc);
   bool ParseDirectiveCFIRememberState(StringRef, SMLoc DirectiveLoc);
   bool ParseDirectiveCFIRestoreState(StringRef, SMLoc DirectiveLoc);
@@ -2351,7 +2361,7 @@ bool GenericAsmParser::ParseDirectiveCFIDefCfaRegister(StringRef,
 }
 
 /// ParseDirectiveCFIOffset
-/// ::= .cfi_off register, offset
+/// ::= .cfi_offset register, offset
 bool GenericAsmParser::ParseDirectiveCFIOffset(StringRef, SMLoc DirectiveLoc) {
   int64_t Register = 0;
   int64_t Offset = 0;
@@ -2369,6 +2379,28 @@ bool GenericAsmParser::ParseDirectiveCFIOffset(StringRef, SMLoc DirectiveLoc) {
   return getStreamer().EmitCFIOffset(Register, Offset);
 }
 
+/// ParseDirectiveCFIRelOffset
+/// ::= .cfi_rel_offset register, offset
+bool GenericAsmParser::ParseDirectiveCFIRelOffset(StringRef,
+                                                  SMLoc DirectiveLoc) {
+  int64_t Register = 0;
+
+  if (ParseRegisterOrRegisterNumber(Register, DirectiveLoc))
+    return true;
+
+  if (getLexer().isNot(AsmToken::Comma))
+    return TokError("unexpected token in directive");
+  Lex();
+
+  int64_t Offset = 0;
+  if (getParser().ParseAbsoluteExpression(Offset))
+    return true;
+
+  Offset -= getParser().getLastOffset();
+
+  return getStreamer().EmitCFIOffset(Register, Offset);
+}
+
 static bool isValidEncoding(int64_t Encoding) {
   if (Encoding & ~0xff)
     return false;

diff --git a/test/MC/ELF/cfi-rel-offset.s b/test/MC/ELF/cfi-rel-offset.s
new file mode 100644 (file)
index 0000000..87c0cf3
--- /dev/null
+++ b/test/MC/ELF/cfi-rel-offset.s
@@ -0,0 +1,49 @@
+// RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o - | elf-dump  --dump-section-data | FileCheck %s
+
+f:
+       .cfi_startproc
+        nop
+        .cfi_def_cfa_offset 8
+        nop
+        .cfi_def_cfa_register 6
+        nop
+        .cfi_rel_offset 6,16
+        nop
+        .cfi_def_cfa_offset 16
+        nop
+        .cfi_rel_offset 6,0
+       .cfi_endproc
+
+// CHECK:       # Section 0x00000004
+// CHECK-NEXT:  (('sh_name', 0x00000011) # '.eh_frame'
+// CHECK-NEXT:   ('sh_type', 0x00000001)
+// CHECK-NEXT:   ('sh_flags', 0x00000002)
+// CHECK-NEXT:   ('sh_addr', 0x00000000)
+// CHECK-NEXT:   ('sh_offset', 0x00000048)
+// CHECK-NEXT:   ('sh_size', 0x00000040)
+// CHECK-NEXT:   ('sh_link', 0x00000000)
+// CHECK-NEXT:   ('sh_info', 0x00000000)
+// CHECK-NEXT:   ('sh_addralign', 0x00000008)
+// CHECK-NEXT:   ('sh_entsize', 0x00000000)
+// CHECK-NEXT:   ('_section_data', '14000000 00000000 017a5200 01781001 1b0c0708 90010000 24000000 1c000000 00000000 05000000 00410e08 410d0641 11067f41 0e104186 02000000 00000000')
+// CHECK-NEXT:  ),
+// CHECK-NEXT:  # Section 0x00000005
+// CHECK-NEXT:  (('sh_name', 0x0000000c) # '.rela.eh_frame'
+// CHECK-NEXT:   ('sh_type', 0x00000004)
+// CHECK-NEXT:   ('sh_flags', 0x00000000)
+// CHECK-NEXT:   ('sh_addr', 0x00000000)
+// CHECK-NEXT:   ('sh_offset', 0x000003a0)
+// CHECK-NEXT:   ('sh_size', 0x00000018)
+// CHECK-NEXT:   ('sh_link', 0x00000007)
+// CHECK-NEXT:   ('sh_info', 0x00000004)
+// CHECK-NEXT:   ('sh_addralign', 0x00000008)
+// CHECK-NEXT:   ('sh_entsize', 0x00000018)
+// CHECK-NEXT:   ('_relocations', [
+// CHECK-NEXT:    # Relocation 0x00000000
+// CHECK-NEXT:    (('r_offset', 0x00000020)
+// CHECK-NEXT:     ('r_sym', 0x00000002)
+// CHECK-NEXT:     ('r_type', 0x00000002)
+// CHECK-NEXT:     ('r_addend', 0x00000000)
+// CHECK-NEXT:    ),
+// CHECK-NEXT:   ])
+// CHECK-NEXT:  ),