ARM assembly 'cmp lr, #0' should not encode using 'cmn'.
The CMP->CMN alias was matching for an immediate of zero when it
should only match for negative values.
rdar://11129224
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153689 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
index 911eb13..e002206 100644
--- a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
@@ -782,7 +782,8 @@
const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(getImm());
if (!CE) return false;
int64_t Value = CE->getValue();
- return ARM_AM::getSOImmVal(-Value) != -1;
+ // Negation must be representable as an so_imm and be non-zero.
+ return Value && ARM_AM::getSOImmVal(-Value) != -1;
}
bool isT2SOImm() const {
if (!isImm()) return false;
@@ -803,7 +804,8 @@
const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(getImm());
if (!CE) return false;
int64_t Value = CE->getValue();
- return ARM_AM::getT2SOImmVal(-Value) != -1;
+ // Negation must be representable as a t2_so_imm and be non-zero.
+ return Value && ARM_AM::getT2SOImmVal(-Value) != -1;
}
bool isSetEndImm() const {
if (!isImm()) return false;