Unverified Commit 2fd343e5 authored by Jon Roelofs's avatar Jon Roelofs
Browse files

[MC][AsmParser] Diagnose improperly nested .cfi frames 

This showed up when simplifying some large testcase, where the cfi directives
became out of sync with the proc's they enclose.

rdar://111459507

Differential revision: https://reviews.llvm.org/D155245

This reverts commit 4172fcc1.
parent fac5ab66

lld/test/COFF/gc-dwarf-eh.s

+2 −2
Original line number Diff line number Diff line
@@ -13,9 +13,9 @@ 
	.def	_main; .scl	2; .type	32; .endef

	.section	.text,"xr",one_only,_main

	.globl	_main

_main:

	.cfi_startproc

	.cfi_personality 0, ___gxx_personality_v0

_main:

	xorl	%eax, %eax

	ret

	.cfi_endproc
@@ -29,8 +29,8 @@ ___gxx_personality_v0: 
	.def	_unused; .scl	2; .type	32; .endef

	.section	.text,"xr",one_only,_unused

	.globl	_unused

_unused:

	.cfi_startproc

	.cfi_personality 0, ___gxx_personality_v0

_unused:

	ret

	.cfi_endproc

llvm/lib/MC/MCParser/AsmParser.cpp

+11 −0
Original line number Diff line number Diff line
@@ -125,6 +125,7 @@ private: 
  void *SavedDiagContext;

  std::unique_ptr<MCAsmParserExtension> PlatformParser;

  SMLoc StartTokLoc;

  std::optional<SMLoc> CFIStartProcLoc;



  /// This is the current buffer index we're lexing from as managed by the

  /// SourceMgr object.
@@ -1949,6 +1950,11 @@ bool AsmParser::parseStatement(ParseStatementInfo &Info, 
      Lex();

    }



    if (CFIStartProcLoc && Sym->isExternal())

      return Error(StartTokLoc, "non-private labels cannot appear between "

                                ".cfi_startproc / .cfi_endproc pairs") &&

             Error(*CFIStartProcLoc, "previous .cfi_startproc was here");



    if (discardLTOSymbol(IDVal))

      return false;
@@ -4193,6 +4199,8 @@ bool AsmParser::parseDirectiveCFISections() { 
/// parseDirectiveCFIStartProc

/// ::= .cfi_startproc [simple]

bool AsmParser::parseDirectiveCFIStartProc() {

  CFIStartProcLoc = StartTokLoc;



  StringRef Simple;

  if (!parseOptionalToken(AsmToken::EndOfStatement)) {

    if (check(parseIdentifier(Simple) || Simple != "simple",
@@ -4213,8 +4221,11 @@ bool AsmParser::parseDirectiveCFIStartProc() { 
/// parseDirectiveCFIEndProc

/// ::= .cfi_endproc

bool AsmParser::parseDirectiveCFIEndProc() {

  CFIStartProcLoc = std::nullopt;



  if (parseEOL())

    return true;



  getStreamer().emitCFIEndProc();

  return false;

}

llvm/test/MC/AArch64/cfi-bad-nesting.s

0 → 100644
+23 −0
Original line number Diff line number Diff line 
; RUN: not llvm-mc -triple arm64-apple-darwin %s -filetype=obj -o /dev/null 2>&1 | FileCheck %s



; REQUIRES: aarch64-registered-target



	.section	__TEXT,locomotive,regular,pure_instructions



	.globl	_locomotive

	.p2align	2

_locomotive:

	.cfi_startproc

	ret



	; It is invalid to have a non-private label between .cfi_startproc / .cfi_endproc

	.section	__TEXT,__text,regular,pure_instructions

	.globl	_caboose

	.p2align	2

_caboose:

; CHECK: [[#@LINE-1]]:1: error: non-private labels cannot appear between .cfi_startproc / .cfi_endproc pairs

; CHECK: [[#@LINE-9]]:2: error: previous .cfi_startproc was here

	ret

	.cfi_endproc



.subsections_via_symbols
 
 No newline at end of file