[llvm] e395915 - [RISCV] Verify SEW/VecPolicy immediate values

[Philip Reames via llvm-commits]

Author: Philip Reames
Date: 2022-09-14T14:45:16-07:00
New Revision: e395915ac01ffd9b6cf743f361df7265f319a8c7

URL: https://github.com/llvm/llvm-project/commit/e395915ac01ffd9b6cf743f361df7265f319a8c7
DIFF: https://github.com/llvm/llvm-project/commit/e395915ac01ffd9b6cf743f361df7265f319a8c7.diff

LOG: [RISCV] Verify SEW/VecPolicy immediate values

Copy the asserts from the printing code, and turn them into actual verifier rules. Doing this revealed an existing bug - see 0a14551.

Differential Revision: https://reviews.llvm.org/D133869

Added: 
    

Modified: 
    llvm/lib/Target/RISCV/RISCVInstrInfo.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/RISCV/RISCVInstrInfo.cpp b/llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
index 2307ba5c2ee46..795dc04587a14 100644
--- a/llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
+++ b/llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
@@ -1219,6 +1219,29 @@ bool RISCVInstrInfo::verifyInstruction(const MachineInstr &MI,
     }
   }
 
+  const uint64_t TSFlags = Desc.TSFlags;
+  if (RISCVII::hasSEWOp(TSFlags)) {
+    unsigned OpIdx = RISCVII::getSEWOpNum(Desc);
+    uint64_t Log2SEW = MI.getOperand(OpIdx).getImm();
+    if (Log2SEW > 31) {
+      ErrInfo = "Unexpected SEW value";
+      return false;
+    }
+    unsigned SEW = Log2SEW ? 1 << Log2SEW : 8;
+    if (!RISCVVType::isValidSEW(SEW)) {
+      ErrInfo = "Unexpected SEW value";
+      return false;
+    }
+  }
+  if (RISCVII::hasVecPolicyOp(TSFlags)) {
+    unsigned OpIdx = RISCVII::getVecPolicyOpNum(Desc);
+    uint64_t Policy = MI.getOperand(OpIdx).getImm();
+    if (Policy > (RISCVII::TAIL_AGNOSTIC | RISCVII::MASK_AGNOSTIC)) {
+      ErrInfo = "Invalid Policy Value";
+      return false;
+    }
+  }
+
   return true;
 }