[DWARF] Added verification check for die ranges. If highPC is an address, then it should be greater than lowPC for each range.

Differential Revision: https://reviews.llvm.org/D35733

llvm-svn: 308928

llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h

@@ -73,6 +73,15 @@ class DWARFVerifier {
 
 
   bool verifyUnitContents(DWARFUnit Unit);
+
+  /// Verify that all Die ranges are valid.
+  ///
+  /// This function currently checks for:
+  /// - cases in which lowPC >= highPC
+  ///
+  /// \returns Number of errors that occured during verification.
+  unsigned verifyDieRanges(const DWARFDie &Die);
+
   /// Verifies the attribute's DWARF attribute and its value.
   ///
   /// This function currently checks for:

llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp

@@ -94,6 +94,7 @@ bool DWARFVerifier::verifyUnitContents(DWARFUnit Unit) {
     auto Die = Unit.getDIEAtIndex(I);
     if (Die.getTag() == DW_TAG_null)
       continue;
+    NumUnitErrors += verifyDieRanges(Die);
     for (auto AttrValue : Die.attributes()) {
       NumUnitErrors += verifyDebugInfoAttribute(Die, AttrValue);
       NumUnitErrors += verifyDebugInfoForm(Die, AttrValue);
@@ -209,6 +210,18 @@ bool DWARFVerifier::handleDebugInfo() {
   return (isHeaderChainValid && NumDebugInfoErrors == 0);
 }
 
+unsigned DWARFVerifier::verifyDieRanges(const DWARFDie &Die) {
+  unsigned NumErrors = 0;
+  for (auto Range : Die.getAddressRanges()) {
+    if (Range.LowPC >= Range.HighPC) {
+      ++NumErrors;
+      OS << format("error: Invalid address range [0x%08x - 0x%08x].\n",
+                   Range.LowPC, Range.HighPC);
+    }
+  }
+  return NumErrors;
+}
+
 unsigned DWARFVerifier::verifyDebugInfoAttribute(const DWARFDie &Die,
                                                  DWARFAttribute &AttrValue) {
   const DWARFObject &DObj = DCtx.getDWARFObj();

llvm/test/tools/llvm-dwarfdump/X86/verify_die_ranges.s

@@ -0,0 +1,82 @@
+# RUN: llvm-mc %s -filetype obj -triple x86_64-apple-darwin -o - \
+# RUN: | not llvm-dwarfdump -verify - \
+# RUN: | FileCheck %s
+
+# CHECK: Verifying .debug_info Unit Header Chain...
+# CHECK-NEXT: error: Invalid address range [0x00000007 - 0x00000006].
+
+	.section	__TEXT,__text,regular,pure_instructions
+	.macosx_version_min 10, 12
+	.globl	_foo                    ## -- Begin function foo
+	.p2align	4, 0x90
+_foo:                                   ## @foo
+Lfunc_begin0:
+	.file	1 "basic.c"
+	.loc	1 1 0                   ## basic.c:1:0
+	.cfi_startproc
+## BB#0:                                ## %entry
+	pushq	%rbp
+Lcfi0:
+	.cfi_def_cfa_offset 16
+Lcfi1:
+	.cfi_offset %rbp, -16
+	movq	%rsp, %rbp
+Lcfi2:
+	.cfi_def_cfa_register %rbp
+Ltmp0:
+	.loc	1 1 17 prologue_end     ## basic.c:1:17
+	popq	%rbp
+	retq
+Ltmp1:
+Lfunc_end0:
+	.cfi_endproc
+                                        ## -- End function
+	.section	__DWARF,__debug_str,regular,debug
+Linfo_string:
+	.asciz	"clang version 6.0.0 (trunk 308773) (llvm/trunk 308774)" ## string offset=0
+	.asciz	"basic.c"               ## string offset=55
+	.asciz	"/Users/sgravani/Development/tests" ## string offset=63
+	.asciz	"foo"                   ## string offset=97
+	.section	__DWARF,__debug_abbrev,regular,debug
+Lsection_abbrev:
+	.byte	1                       ## Abbreviation Code
+	.byte	17                      ## DW_TAG_compile_unit
+	.byte	1                       ## DW_CHILDREN_yes
+	.byte	37                      ## DW_AT_producer
+	.byte	14                      ## DW_FORM_strp
+	.byte	19                      ## DW_AT_language
+	.byte	5                       ## DW_FORM_data2
+	.byte	3                       ## DW_AT_name
+	.byte	14                      ## DW_FORM_strp
+	.byte	16                      ## DW_AT_stmt_list
+	.byte	6                       ## DW_FORM_data4
+	.byte	27                      ## DW_AT_comp_dir
+	.byte	14                      ## DW_FORM_strp
+	.byte	17                      ## DW_AT_low_pc
+	.byte	1                       ## DW_FORM_addr
+	.byte	18                      ## DW_AT_high_pc
+	.byte	1                       ## DW_FORM_addr
+	.byte	0                       ## EOM(1)
+	.byte	0                       ## EOM(2)
+	.section	__DWARF,__debug_info,regular,debug
+Lsection_info:
+Lcu_begin0:
+	.long	43                      ## Length of Unit
+	.short	3                       ## DWARF version number
+Lset0 = Lsection_abbrev-Lsection_abbrev ## Offset Into Abbrev. Section
+	.long	Lset0
+	.byte	8                       ## Address Size (in bytes)
+	.byte	1                       ## Abbrev [1] 0xb:0x3f DW_TAG_compile_unit
+	.long	0                       ## DW_AT_producer
+	.short	12                      ## DW_AT_language
+	.long	55                      ## DW_AT_name
+Lset1 = Lline_table_start0-Lsection_line ## DW_AT_stmt_list
+	.long	Lset1
+	.long	63                      ## DW_AT_comp_dir
+	.quad	Lfunc_end0 + 1          ## DW_AT_low_pc -- error: Invalid address range [0x00000007 - 0x00000006].
+	.quad	Lfunc_end0              ## DW_AT_high_pc
+	.byte	0                       ## End Of Children Mark
+.subsections_via_symbols
+	.section	__DWARF,__debug_line,regular,debug
+Lsection_line:
+Lline_table_start0: