From b80dbdb77d373cda27b00a742f17d1c385dc4a46 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Arne=20D=C3=B6ring?= <arne.doering@gmx.net>
Date: Fri, 1 Feb 2019 12:12:10 +0100
Subject: [PATCH] Fix vm signed xor (#10519)

* fix #10482

* undo changes

* fix for bitwise not

* remove dead opcode
---
 compiler/vmgen.nim   |  7 +++++--
 tests/vm/tbitops.nim | 16 +++++++++++-----
 2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/compiler/vmgen.nim b/compiler/vmgen.nim
index 4b1551884f..7f3ca84ae0 100644
--- a/compiler/vmgen.nim
+++ b/compiler/vmgen.nim
@@ -1009,7 +1009,7 @@ proc genMagic(c: PCtx; n: PNode; dest: var TDest; m: TMagic) =
   of mLtPtr, mLtU, mLtU64: genBinaryABC(c, n, dest, opcLtu)
   of mEqProc, mEqRef, mEqUntracedRef:
     genBinaryABC(c, n, dest, opcEqRef)
-  of mXor: genBinaryABCnarrowU(c, n, dest, opcXor)
+  of mXor: genBinaryABC(c, n, dest, opcXor)
   of mNot: genUnaryABC(c, n, dest, opcNot)
   of mUnaryMinusI, mUnaryMinusI64:
     genUnaryABC(c, n, dest, opcUnaryMinusInt)
@@ -1018,7 +1018,10 @@ proc genMagic(c: PCtx; n: PNode; dest: var TDest; m: TMagic) =
   of mUnaryPlusI, mUnaryPlusF64: gen(c, n.sons[1], dest)
   of mBitnotI:
     genUnaryABC(c, n, dest, opcBitnotInt)
-    genNarrowU(c, n, dest)
+    #genNarrowU modified, do not narrow signed types
+    let t = skipTypes(n.typ, abstractVar-{tyTypeDesc})
+    if t.kind in {tyUInt8..tyUInt32} or (t.kind == tyUInt and t.size < 8):
+      c.gABC(n, opcNarrowU, dest, TRegister(t.size*8))
   of mToFloat, mToBiggestFloat, mToInt,
      mToBiggestInt, mCharToStr, mBoolToStr, mIntToStr, mInt64ToStr,
      mFloatToStr, mCStrToStr, mStrToStr, mEnumToStr:
diff --git a/tests/vm/tbitops.nim b/tests/vm/tbitops.nim
index 3d1a8aa0cd..90d463ec96 100644
--- a/tests/vm/tbitops.nim
+++ b/tests/vm/tbitops.nim
@@ -7,25 +7,29 @@ import strutils
 const x  = [1'i32, -1, -10, 10, -10, 10, -20, 30, -40, 50, 7 shl 28, -(7 shl 28), 7 shl 28, -(7 shl 28)]
 const y  = [-1'i32, 1, -10, -10, 10, 10, -20, -30, 40, 50, 1 shl 30, 1 shl 30, -(1 shl 30), -(1 shl 30)]
 
-
 const res_xor = block:
   var tmp: seq[int64]
-  for i in 0..<x.len:
+  for i in 0 ..< x.len:
     tmp.add(int64(x[i] xor y[i]))
   tmp
 
 const res_and = block:
   var tmp: seq[int64]
-  for i in 0..<x.len:
+  for i in 0 ..< x.len:
     tmp.add(int64(x[i] and y[i]))
   tmp
- 
+
 const res_or = block:
   var tmp: seq[int64]
-  for i in 0..<x.len:
+  for i in 0 ..< x.len:
     tmp.add(int64(x[i] or y[i]))
   tmp
 
+const res_not = block:
+  var tmp: seq[int64]
+  for i in 0 ..< x.len:
+    tmp.add(not x[i])
+  tmp
 
 let xx = x
 let yy = y
@@ -34,6 +38,8 @@ for i in 0..<xx.len:
   let z_xor = int64(xx[i] xor yy[i])
   let z_and = int64(xx[i] and yy[i])
   let z_or = int64(xx[i] or yy[i])
+  let z_not = int64(not xx[i])
   doAssert(z_xor == res_xor[i], $i & ": " & $res_xor[i] & "  " & $z_xor)
   doAssert(z_and == res_and[i], $i & ": " & $res_and[i] & "  " & $z_and)
   doAssert(z_or == res_or[i], $i & ": " & $res_or[i] & "  " & $z_or)
+  doAssert(z_not == res_not[i], $i & ": " & $res_not[i] & "  " & $z_not)