arch-riscv: Make use of ImmOp's polymorphism

This patch makes use of ImmOp's polymorphism to remove unnecessary
casting from the implementations of arithmetic instructions with
immediate operands and to remove the CUIOp format by combining it with
the CIOp format (compressed arithmetic instructions with immediate
operands). Interestingly, RISC-V specifies that instructions with
unsigned immediate operands still need to sign-extend the immediates
from 12 (or 20) bits to 64 bits, so that is left alone.

Change-Id: If20d70c1e90f379b9ed8a4155b2b9222b6defe16
Reviewed-on: https://gem5-review.googlesource.com/6401
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Tuan Ta <qtt2@cornell.edu>
Maintainer: Alec Roelke <ar4jc@virginia.edu>

2 files changed, 1 insertions, 0 deletions

diff --git a/tests/test-progs/insttest/bin/riscv/linux-rv64i/insttest b/tests/test-progs/insttest/bin/riscv/linux-rv64i/insttest
index a6e5d0203..c5a21739d 100755
--- a/tests/test-progs/insttest/bin/riscv/linux-rv64i/insttest
+++ b/tests/test-progs/insttest/bin/riscv/linux-rv64i/insttest
diff --git a/tests/test-progs/insttest/src/riscv/rv64i.cpp b/tests/test-progs/insttest/src/riscv/rv64i.cpp
index 95e8ee02a..cfe5e298d 100644
--- a/tests/test-progs/insttest/src/riscv/rv64i.cpp
+++ b/tests/test-progs/insttest/src/riscv/rv64i.cpp
@@ -137,6 +137,7 @@ int main()
     // SLTIU
     expect<bool>(false, []{return I::sltiu(-1, 0);}, "sltiu, false");
     expect<bool>(true, []{return I::sltiu(0, -1);}, "sltiu, true");
+    expect<bool>(true, []{return I::sltiu(0xFFFF, -1);}, "sltiu, sext");
 
     // XORI
     expect<uint64_t>(0xFF, []{return I::xori(0xAA, 0x55);}, "xori (1)");