From: Tuan Ta <qtt2@cornell.edu>
Date: Mon, 2 Apr 2018 20:22:30 +0000 (-0400)
Subject: riscv: fixed syscall return value
X-Git-Tag: v19.0.0.0~1171
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=2eb57c7c3bb762097aa7bdab40cd37ec73996dca;p=gem5.git

riscv: fixed syscall return value

In case of failure, a syscall returns a negative value encoding the
error code. This patch makes the risc-v implementation returns the
encoded value instead of its absolute value upon a failure of a syscall.

Change-Id: I6032b0337fe1cff5b326dbc6bb3b87a415f03300
Reviewed-on: https://gem5-review.googlesource.com/c/9627
Reviewed-by: Alec Roelke <ar4jc@virginia.edu>
Maintainer: Alec Roelke <ar4jc@virginia.edu>
---

diff --git a/src/arch/riscv/process.cc b/src/arch/riscv/process.cc
index ed6de1546..16d0dc7ff 100644
--- a/src/arch/riscv/process.cc
+++ b/src/arch/riscv/process.cc
@@ -279,6 +279,6 @@ RiscvProcess::setSyscallReturn(ThreadContext *tc, SyscallReturn sysret)
         tc->setIntReg(SyscallPseudoReturnReg, sysret.returnValue());
     } else {
         // got an error, return details
-        tc->setIntReg(SyscallPseudoReturnReg, sysret.errnoValue());
+        tc->setIntReg(SyscallPseudoReturnReg, sysret.encodedValue());
     }
 }