[PATCH] D23312: [Thumb] Validate branch target for CBZ/CBNZ instructions.

[Oliver Stannard via llvm-commits]

olista01 added a subscriber: olista01.

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Comment at: lib/Target/ARM/AsmParser/ARMAsmParser.cpp:863
@@ -862,1 +862,3 @@
 
+  bool isPositiveOffset() const {
+    if (!isImm()) return false;
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Why don't you use isUnsignedOffset, which would also check the upper limit and alignment?

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Comment at: lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp:582
@@ +581,3 @@
+    // CB instructions cannot branch backwards with a negative offset
+    if (Ctx && (int64_t)Value < 0) {
+      Ctx->reportError(Fixup.getLoc(), "out of range pc-relative fixup value");
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We should also check the upper bound and alignment here.


Repository:
  rL LLVM

https://reviews.llvm.org/D23312