fixup! [CHERI StdCompat] Expand CGetSealed

Need to use -1 and not zero!

Author: arichardson

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

@@ -13581,8 +13581,11 @@ SDValue RISCVTargetLowering::PerformDAGCombine(SDNode *N,
             ISD::INTRINSIC_WO_CHAIN, DL, XLenVT,
             DAG.getConstant(Intrinsic::cheri_cap_type_get, DL, MVT::i64),
             N->getOperand(1));
-        // Unsealed capabilities have a zero type, so non-zero means sealed.
-        return DAG.getSetCC(DL, MVT::i1, Type, DAG.getConstant(0, DL, XLenVT),
+        // Note in the RISC-V standard unsealed capabilities have a zero type,
+        // but in ISAv9 unsealed is otype - 1.
+        int64_t UnsealedOtype = Subtarget.hasXCheri() ? -1 : 0;
+        return DAG.getSetCC(DL, MVT::i1, Type,
+                            DAG.getConstant(UnsealedOtype, DL, XLenVT),
                             ISD::SETNE);
       } else {
         SDValue IntRes =

llvm/test/CodeGen/RISCV/cheri/std-compat/get-sealed.ll

@@ -19,7 +19,8 @@ define internal i64 @test(ptr addrspace(200) %cap) addrspace(200) nounwind {
 ; STD-COMPAT-LABEL: test:
 ; STD-COMPAT:       # %bb.0: # %entry
 ; STD-COMPAT-NEXT:    cgettype a0, ca0
-; STD-COMPAT-NEXT:    beqz a0, .LBB0_2
+; STD-COMPAT-NEXT:    li a1, -1
+; STD-COMPAT-NEXT:    beq a0, a1, .LBB0_2
 ; STD-COMPAT-NEXT:  # %bb.1: # %if.then
 ; STD-COMPAT-NEXT:    li a0, 4
 ; STD-COMPAT-NEXT:    cret