[cfi-verify] Abort on unsupported targets

As suggested in the review for r337007, this makes cfi-verify abort on unsupported targets instead of producing incorrect results.  It also updates the design document to reflect this.

Differential Revision: https://reviews.llvm.org/D49304

llvm-svn: 337181

diff --git a/llvm/docs/CFIVerify.rst b/llvm/docs/CFIVerify.rst
index a1182a8..6403347 100644 (file)
--- a/llvm/docs/CFIVerify.rst
+++ b/llvm/docs/CFIVerify.rst
@@ -86,6 +86,8 @@ Only machine code sections that are marked as executable will be subject to this
 analysis. Non-executable sections do not require analysis as any execution
 present in these sections has already violated the control flow integrity.
 
-Suitable extensions may be made at a later date to include anaylsis for indirect
+Suitable extensions may be made at a later date to include analysis for indirect
 control flow operations across DSO boundaries. Currently, these CFI features are
 only experimental with an unstable ABI, making them unsuitable for analysis.
+
+The tool currently only supports the x86, x86_64, and AArch64 architectures.

diff --git a/llvm/test/tools/llvm-cfi-verify/Unsupported/arm-protected-lineinfo.s b/llvm/test/tools/llvm-cfi-verify/Unsupported/arm-protected-lineinfo.s
new file mode 100644 (file)
index 0000000..c985ddb
--- /dev/null
+++ b/llvm/test/tools/llvm-cfi-verify/Unsupported/arm-protected-lineinfo.s
@@ -0,0 +1,232 @@
+# RUN: llvm-mc %s -filetype obj -triple armv7a-- -o %t.o
+# RUN: not llvm-cfi-verify %t.o 2>&1 | FileCheck %s
+
+# CHECK: Could not initialise disassembler: Unsupported architecture.
+
+# Source (tiny.cc):
+#   int a() { return 42; }
+#   int b() { return 137; }
+#   int main(int argc, char** argv) {
+#     int(*ptr)();
+#     if (argc == 1)
+#       ptr = &a;
+#     else
+#       ptr = &b;
+#     return ptr();
+#   }
+       .text
+       .syntax unified
+       .eabi_attribute 67, "2.09"
+       .eabi_attribute 6, 2
+       .eabi_attribute 8, 1
+       .eabi_attribute 9, 1
+       .eabi_attribute 34, 1
+       .eabi_attribute 15, 1
+       .eabi_attribute 16, 1
+       .eabi_attribute 17, 2
+       .eabi_attribute 20, 1
+       .eabi_attribute 21, 1
+       .eabi_attribute 23, 3
+       .eabi_attribute 24, 1
+       .eabi_attribute 25, 1
+       .eabi_attribute 38, 1
+       .eabi_attribute 18, 4
+       .eabi_attribute 26, 2
+       .eabi_attribute 14, 0
+       .file   "ld-temp.o"
+       .p2align        2
+       .type   _Z1av.cfi,%function
+       .code   32
+_Z1av.cfi:
+.Lfunc_begin0:
+       .file   1 "tiny.cc"
+       .loc    1 1 0
+       .fnstart
+       .cfi_sections .debug_frame
+       .cfi_startproc
+       .loc    1 1 11 prologue_end
+       mov     r0, #42
+       bx      lr
+.Ltmp0:
+.Lfunc_end0:
+       .size   _Z1av.cfi, .Lfunc_end0-_Z1av.cfi
+       .cfi_endproc
+       .cantunwind
+       .fnend
+
+       .p2align        2
+       .type   _Z1bv.cfi,%function
+       .code   32
+_Z1bv.cfi:
+.Lfunc_begin1:
+       .loc    1 2 0
+       .fnstart
+       .cfi_startproc
+       .loc    1 2 11 prologue_end
+       mov     r0, #137
+       bx      lr
+.Ltmp1:
+.Lfunc_end1:
+       .size   _Z1bv.cfi, .Lfunc_end1-_Z1bv.cfi
+       .cfi_endproc
+       .cantunwind
+       .fnend
+
+       .p2align        2
+       .type   main,%function
+       .code   32
+main:
+.Lfunc_begin2:
+       .loc    1 3 0
+       .fnstart
+       .cfi_startproc
+       .save   {r11, lr}
+       push    {r11, lr}
+       .cfi_def_cfa_offset 8
+       .cfi_offset lr, -4
+       .cfi_offset r11, -8
+       .setfp  r11, sp
+       mov     r11, sp
+       .cfi_def_cfa_register r11
+       .pad    #16
+       sub     sp, sp, #16
+       mov     r2, #0
+       str     r2, [r11, #-4]
+       str     r0, [sp, #8]
+       str     r1, [sp, #4]
+.Ltmp2:
+       .loc    1 5 7 prologue_end
+       ldr     r0, [sp, #8]
+       cmp     r0, #1
+       bne     .LBB2_2
+       b       .LBB2_1
+.LBB2_1:
+       .loc    1 6 9
+       ldr     r0, .LCPI2_0
+.LPC2_0:
+       add     r0, pc, r0
+       str     r0, [sp]
+       .loc    1 6 5 is_stmt 0
+       b       .LBB2_3
+.LBB2_2:
+       .loc    1 8 9 is_stmt 1
+       ldr     r0, .LCPI2_1
+.LPC2_1:
+       add     r0, pc, r0
+       str     r0, [sp]
+       b       .LBB2_3
+.LBB2_3:
+       .loc    1 9 10
+       ldr     r1, [sp]
+       ldr     r0, .LCPI2_2
+.LPC2_2:
+       add     r0, pc, r0
+       sub     r0, r1, r0
+       ror     r0, r0, #2
+       cmp     r0, #2
+       blo     .LBB2_5
+       b       .LBB2_4
+.LBB2_4:
+       .inst   0xe7ffdefe
+.LBB2_5:
+       mov     lr, pc
+       bx      r1
+       .loc    1 9 3 is_stmt 0
+       mov     sp, r11
+       pop     {r11, lr}
+       bx      lr
+.Ltmp3:
+       .p2align        2
+       .loc    1 0 3
+.LCPI2_0:
+       .long   _Z1av-(.LPC2_0+8)
+.LCPI2_1:
+       .long   _Z1bv-(.LPC2_1+8)
+.LCPI2_2:
+       .long   .L.cfi.jumptable-(.LPC2_2+8)
+.Lfunc_end2:
+       .size   main, .Lfunc_end2-main
+       .cfi_endproc
+       .fnend
+
+       .p2align        2
+       .type   .L.cfi.jumptable,%function
+       .code   32
+.L.cfi.jumptable:
+.Lfunc_begin3:
+       .fnstart
+       .cfi_startproc
+       @APP
+       b       _Z1av.cfi
+       b       _Z1bv.cfi
+
+       @NO_APP
+.Lfunc_end3:
+       .size   .L.cfi.jumptable, .Lfunc_end3-.L.cfi.jumptable
+       .cfi_endproc
+       .cantunwind
+       .fnend
+
+       .type   .L__unnamed_1,%object
+       .section        .rodata,"a",%progbits
+.L__unnamed_1:
+       .size   .L__unnamed_1, 0
+
+       .section        .debug_str,"MS",%progbits,1
+.Linfo_string0:
+       .asciz  "clang version 7.0.0 (trunk 336681) (llvm/trunk 336683)"
+.Linfo_string1:
+       .asciz  "tiny.cc"
+.Linfo_string2:
+       .asciz  ""
+       .section        .debug_abbrev,"",%progbits
+       .byte   1
+       .byte   17
+       .byte   0
+       .byte   37
+       .byte   14
+       .byte   19
+       .byte   5
+       .byte   3
+       .byte   14
+       .byte   16
+       .byte   23
+       .byte   27
+       .byte   14
+       .byte   17
+       .byte   1
+       .byte   18
+       .byte   6
+       .byte   0
+       .byte   0
+       .byte   0
+       .section        .debug_info,"",%progbits
+.Lcu_begin0:
+       .long   34
+       .short  4
+       .long   .debug_abbrev
+       .byte   4
+       .byte   1
+       .long   .Linfo_string0
+       .short  4
+       .long   .Linfo_string1
+       .long   .Lline_table_start0
+       .long   .Linfo_string2
+       .long   .Lfunc_begin0
+       .long   .Lfunc_end2-.Lfunc_begin0
+       .section        .debug_ranges,"",%progbits
+       .section        .debug_macinfo,"",%progbits
+       .byte   0
+
+       .globl  __typeid__ZTSFivE_global_addr
+       .hidden __typeid__ZTSFivE_global_addr
+.set __typeid__ZTSFivE_global_addr, .L.cfi.jumptable
+       .size   __typeid__ZTSFivE_global_addr, 1
+       .type   _Z1av,%function
+.set _Z1av, .L.cfi.jumptable
+       .type   _Z1bv,%function
+.set _Z1bv, .L.cfi.jumptable+4
+       .ident  "clang version 7.0.0 (trunk 336681) (llvm/trunk 336683)"
+       .section        ".note.GNU-stack","",%progbits
+       .section        .debug_line,"",%progbits
+.Lline_table_start0:

diff --git a/llvm/test/tools/llvm-cfi-verify/Unsupported/lit.local.cfg b/llvm/test/tools/llvm-cfi-verify/Unsupported/lit.local.cfg
new file mode 100644 (file)
index 0000000..236e1d3
--- /dev/null
+++ b/llvm/test/tools/llvm-cfi-verify/Unsupported/lit.local.cfg
@@ -0,0 +1,2 @@
+if not 'ARM' in config.root.targets:
+    config.unsupported = True

diff --git a/llvm/tools/llvm-cfi-verify/lib/FileAnalysis.cpp b/llvm/tools/llvm-cfi-verify/lib/FileAnalysis.cpp
index 15bf20f..29819d8 100644 (file)
--- a/llvm/tools/llvm-cfi-verify/lib/FileAnalysis.cpp
+++ b/llvm/tools/llvm-cfi-verify/lib/FileAnalysis.cpp
@@ -85,6 +85,16 @@ Expected<FileAnalysis> FileAnalysis::Create(StringRef Filename) {
   if (!Analysis.Object)
     return make_error<UnsupportedDisassembly>("Failed to cast object");
 
+  switch (Analysis.Object->getArch()) {
+    case Triple::x86:
+    case Triple::x86_64:
+    case Triple::aarch64:
+    case Triple::aarch64_be:
+      break;
+    default:
+      return make_error<UnsupportedDisassembly>("Unsupported architecture.");
+  }
+
   Analysis.ObjectTriple = Analysis.Object->makeTriple();
   Analysis.Features = Analysis.Object->getFeatures();