From: Sandipan Das <sandipan@linux.ibm.com>
Date: Sat, 6 Feb 2021 11:47:57 +0000 (+0530)
Subject: arch-power: Add word divide-extended instructions
X-Git-Tag: develop-gem5-snapshot~45
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=6a66360b2a39a86c75036c65ea49f3899abd3bab;p=gem5.git

arch-power: Add word divide-extended instructions

This adds the following instructions.
  * Divide Word Extended (divwe[o][.])
  * Divide Word Extended Unsigned (divweu[o][.])

Change-Id: Ie399269938c8e120ece667ce3fc9c6fe1d74faca
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
---

diff --git a/src/arch/power/isa/decoder.isa b/src/arch/power/isa/decoder.isa
index 4297d7d14..79fe314df 100644
--- a/src/arch/power/isa/decoder.isa
+++ b/src/arch/power/isa/decoder.isa
@@ -629,6 +629,44 @@ decode PO default Unknown::unknown() {
                     }
                 }},
                 true);
+
+                427: divwe({{
+                    int32_t src1 = Ra_sw;
+                    int32_t src2 = Rb_sw;
+                    int64_t res;
+                    if ((src1 != INT32_MIN || src2 != -1) && src2 != 0) {
+                        res = ((int64_t)src1 << 32) / src2;
+                        if (res == (int32_t)res) {
+                            Rt = (uint32_t)res;
+                        } else {
+                            Rt = 0;
+                            setOV = true;
+                        }
+                    } else {
+                        Rt = 0;
+                        setOV = true;
+                    }
+                }},
+                true);
+
+                395: divweu({{
+                    uint32_t src1 = Ra_ud;
+                    uint32_t src2 = Rb_ud;
+                    uint64_t res;
+                    if (src2 != 0) {
+                        res = ((uint64_t)src1 << 32) / src2;
+                        if (res <= UINT32_MAX) {
+                            Rt = (uint32_t)res;
+                        } else {
+                            Rt = 0;
+                            setOV = true;
+                        }
+                    } else {
+                        Rt = 0;
+                        setOV = true;
+                    }
+                }},
+                true);
             }
 
             default: decode XFX_XO {