Correctly disassemble truncated asm.
Patch by Richard Simth.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122962 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c b/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c
index 1fd6685..0af510c 100644
--- a/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c
+++ b/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c
@@ -511,7 +511,8 @@
insn->opcode);
if (hasModRMExtension) {
- readModRM(insn);
+ if (readModRM(insn))
+ return -1;
*instructionID = decode(insn->opcodeType,
instructionClass,
@@ -860,7 +861,8 @@
if (insn->consumedModRM)
return 0;
- consumeByte(insn, &insn->modRM);
+ if (consumeByte(insn, &insn->modRM))
+ return -1;
insn->consumedModRM = TRUE;
mod = modFromModRM(insn->modRM);
diff --git a/test/MC/Disassembler/X86/truncated-input.txt b/test/MC/Disassembler/X86/truncated-input.txt
new file mode 100644
index 0000000..34cf038
--- /dev/null
+++ b/test/MC/Disassembler/X86/truncated-input.txt
@@ -0,0 +1,4 @@
+# RUN: llvm-mc --disassemble %s -triple=x86_64-apple-darwin9 |& FileCheck %s
+
+# CHECK: warning
+0x00
diff --git a/tools/llvm-mc/Disassembler.cpp b/tools/llvm-mc/Disassembler.cpp
index e5c31ca..c29d82a 100644
--- a/tools/llvm-mc/Disassembler.cpp
+++ b/tools/llvm-mc/Disassembler.cpp
@@ -44,7 +44,7 @@
uint64_t getExtent() const { return Bytes.size(); }
int readByte(uint64_t Addr, uint8_t *Byte) const {
- if (Addr > getExtent())
+ if (Addr >= getExtent())
return -1;
*Byte = Bytes[Addr].first;
return 0;