Fix treatment of ARM unallocated hint instructions.

The reference manual defines only 5 permitted values for the immediate field of the "hint" instruction:
1. nop (imm == 0)
2. yield (imm == 1)
3. wfe (imm == 2)
4. wfi (imm == 3)
5. sev (imm == 4)

Therefore, restrict the permitted values for the "hint" instruction to 0 through 4.

Patch by Mihail Popa <Mihail.Popa@arm.com>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179707 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 0 deletions

diff --git a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
index a8ff9e6b9c..c024e726d5 100644
--- a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
@@ -610,6 +610,13 @@ public:
     int64_t Value = CE->getValue();
     return ((Value & 3) == 0) && Value >= -1020 && Value <= 1020;
   }
+  bool isImm0_4() const {
+    if (!isImm()) return false;
+    const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(getImm());
+    if (!CE) return false;
+    int64_t Value = CE->getValue();
+    return Value >= 0 && Value < 5;
+  }
   bool isImm0_1020s4() const {
     if (!isImm()) return false;
     const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(getImm());