Get rid of the >>> operator and make >> logical or arithmetic dependi…

…ng on the signedness. Closes rust-lang#2417.

src/librustsyntax/ast.rs

@@ -201,9 +201,8 @@ enum binop {
     bitxor,
     bitand,
     bitor,
-    lsl,
-    lsr,
-    asr,
+    shl,
+    shr,
     eq,
     lt,
     le,

src/librustsyntax/ast_util.rs

@@ -72,9 +72,8 @@ fn binop_to_str(op: binop) -> str {
       bitxor { ret "^"; }
       bitand { ret "&"; }
       bitor { ret "|"; }
-      lsl { ret "<<"; }
-      lsr { ret ">>"; }
-      asr { ret ">>>"; }
+      shl { ret "<<"; }
+      shr { ret ">>"; }
       eq { ret "=="; }
       lt { ret "<"; }
       le { ret "<="; }
@@ -90,9 +89,8 @@ pure fn lazy_binop(b: binop) -> bool {
 
 pure fn is_shift_binop(b: binop) -> bool {
     alt b {
-      lsl { true }
-      lsr { true }
-      asr { true }
+      shl { true }
+      shr { true }
       _ { false }
     }
 }
@@ -353,7 +351,7 @@ fn operator_prec(op: ast::binop) -> uint {
       mul | div | rem   { 12u }
       // 'as' sits between here with 11
       add | subtract    { 10u }
-      lsl | lsr | asr   {  9u }
+      shl | shr         {  9u }
       bitand            {  8u }
       bitxor            {  7u }
       bitor             {  6u }

src/librustsyntax/parse/common.rs

@@ -114,10 +114,8 @@ fn check_restricted_keywords_(p: parser, w: ast::ident) {
 fn expect_gt(p: parser) {
     if p.token == token::GT {
         p.bump();
-    } else if p.token == token::BINOP(token::LSR) {
+    } else if p.token == token::BINOP(token::SHR) {
         p.swap(token::GT, p.span.lo + 1u, p.span.hi);
-    } else if p.token == token::BINOP(token::ASR) {
-        p.swap(token::BINOP(token::LSR), p.span.lo + 1u, p.span.hi);
     } else {
         let mut s: str = "expecting ";
         s += token_to_str(p.reader, token::GT);
@@ -132,8 +130,7 @@ fn parse_seq_to_before_gt<T: copy>(sep: option<token::token>,
                                   p: parser) -> [T] {
     let mut first = true;
     let mut v = [];
-    while p.token != token::GT && p.token != token::BINOP(token::LSR) &&
-              p.token != token::BINOP(token::ASR) {
+    while p.token != token::GT && p.token != token::BINOP(token::SHR) {
         alt sep {
           some(t) { if first { first = false; } else { expect(p, t); } }
           _ { }

src/librustsyntax/parse/lexer.rs

@@ -392,7 +392,7 @@ fn next_token_inner(rdr: reader) -> token::token {
         rdr.bump();
         alt rdr.curr {
           '=' { rdr.bump(); ret token::LE; }
-          '<' { ret binop(rdr, token::LSL); }
+          '<' { ret binop(rdr, token::SHL); }
           '-' {
             rdr.bump();
             alt rdr.curr {
@@ -407,12 +407,7 @@ fn next_token_inner(rdr: reader) -> token::token {
         rdr.bump();
         alt rdr.curr {
           '=' { rdr.bump(); ret token::GE; }
-          '>' {
-            if rdr.next() == '>' {
-                rdr.bump();
-                ret binop(rdr, token::ASR);
-            } else { ret binop(rdr, token::LSR); }
-          }
+          '>' { ret binop(rdr, token::SHR); }
           _ { ret token::GT; }
         }
       }

src/librustsyntax/parse/parser.rs

@@ -1119,9 +1119,8 @@ fn parse_assign_expr(p: parser) -> @expr {
           token::CARET { aop = bitxor; }
           token::AND { aop = bitand; }
           token::OR { aop = bitor; }
-          token::LSL { aop = lsl; }
-          token::LSR { aop = lsr; }
-          token::ASR { aop = asr; }
+          token::SHL { aop = shl; }
+          token::SHR { aop = shr; }
         }
         p.get_id(); // see ast_util::op_expr_callee_id
         ret mk_expr(p, lo, rhs.span.hi, expr_assign_op(aop, lhs, rhs));

src/librustsyntax/parse/prec.rs

@@ -25,9 +25,8 @@ fn token_to_binop(tok: token) -> option<ast::binop> {
       // 'as' sits between here with 11
       BINOP(PLUS)    { some(add) }
       BINOP(MINUS)   { some(subtract) }
-      BINOP(LSL)     { some(lsl) }
-      BINOP(LSR)     { some(lsr) }
-      BINOP(ASR)     { some(asr) }
+      BINOP(SHL)     { some(shl) }
+      BINOP(SHR)     { some(shr) }
       BINOP(AND)     { some(bitand) }
       BINOP(CARET)   { some(bitxor) }
       BINOP(OR)      { some(bitor) }

src/librustsyntax/parse/token.rs

@@ -14,9 +14,8 @@ enum binop {
     CARET,
     AND,
     OR,
-    LSL,
-    LSR,
-    ASR,
+    SHL,
+    SHR,
 }
 
 enum token {
@@ -78,9 +77,8 @@ fn binop_to_str(o: binop) -> str {
       CARET { ret "^"; }
       AND { ret "&"; }
       OR { ret "|"; }
-      LSL { ret "<<"; }
-      LSR { ret ">>"; }
-      ASR { ret ">>>"; }
+      SHL { ret "<<"; }
+      SHR { ret ">>"; }
     }
 }
 

src/rustc/middle/const_eval.rs

@@ -44,8 +44,7 @@ fn eval_const_expr(tcx: middle::ty::ctxt, e: @expr) -> const_val {
               mul { const_int(a * b) } div { const_int(a / b) }
               rem { const_int(a % b) } and | bitand { const_int(a & b) }
               or | bitor { const_int(a | b) } bitxor { const_int(a ^ b) }
-              lsl { const_int(a << b) } lsr { const_int(a >> b) }
-              asr { const_int(a >>> b) }
+              shl { const_int(a << b) } shr { const_int(a >> b) }
               eq { fromb(a == b) } lt { fromb(a < b) }
               le { fromb(a <= b) } ne { fromb(a != b) }
               ge { fromb(a >= b) } gt { fromb(a > b) }
@@ -58,9 +57,7 @@ fn eval_const_expr(tcx: middle::ty::ctxt, e: @expr) -> const_val {
               mul { const_uint(a * b) } div { const_uint(a / b) }
               rem { const_uint(a % b) } and | bitand { const_uint(a & b) }
               or | bitor { const_uint(a | b) } bitxor { const_uint(a ^ b) }
-              lsl { const_int((a << b) as i64) }
-              lsr { const_int((a >> b) as i64) }
-              asr { const_int((a >>> b) as i64) }
+              shl { const_uint(a << b) } shr { const_uint(a >> b) }
               eq { fromb(a == b) } lt { fromb(a < b) }
               le { fromb(a <= b) } ne { fromb(a != b) }
               ge { fromb(a >= b) } gt { fromb(a > b) }

src/rustc/middle/trans/base.rs

@@ -1617,9 +1617,12 @@ fn trans_eager_binop(cx: block, op: ast::binop, lhs: ValueRef,
       ast::bitor { Or(cx, lhs, rhs) }
       ast::bitand { And(cx, lhs, rhs) }
       ast::bitxor { Xor(cx, lhs, rhs) }
-      ast::lsl { Shl(cx, lhs, rhs) }
-      ast::lsr { LShr(cx, lhs, rhs) }
-      ast::asr { AShr(cx, lhs, rhs) }
+      ast::shl { Shl(cx, lhs, rhs) }
+      ast::shr {
+        if ty::type_is_signed(intype) {
+            AShr(cx, lhs, rhs)
+        } else { LShr(cx, lhs, rhs) }
+      }
       _ {
         let cmpr = trans_compare(cx, op, lhs, lhs_t, rhs, rhs_t);
         cx = cmpr.bcx;
@@ -4565,9 +4568,11 @@ fn trans_const_expr(cx: @crate_ctxt, e: @ast::expr) -> ValueRef {
           ast::bitxor { llvm::LLVMConstXor(te1, te2) }
           ast::bitand { llvm::LLVMConstAnd(te1, te2) }
           ast::bitor  { llvm::LLVMConstOr(te1, te2) }
-          ast::lsl    { llvm::LLVMConstShl(te1, te2) }
-          ast::lsr    { llvm::LLVMConstLShr(te1, te2) }
-          ast::asr    { llvm::LLVMConstAShr(te1, te2) }
+          ast::shl    { llvm::LLVMConstShl(te1, te2) }
+          ast::shr    {
+            if signed { llvm::LLVMConstAShr(te1, te2) }
+            else      { llvm::LLVMConstLShr(te1, te2) }
+          }
           ast::eq     |
           ast::lt     |
           ast::le     |

src/rustc/middle/ty.rs

@@ -2704,9 +2704,8 @@ fn is_binopable(_cx: ctxt, ty: t, op: ast::binop) -> bool {
           ast::bitxor { opcat_bit }
           ast::bitand { opcat_bit }
           ast::bitor { opcat_bit }
-          ast::lsl { opcat_shift }
-          ast::lsr { opcat_shift }
-          ast::asr { opcat_shift }
+          ast::shl { opcat_shift }
+          ast::shr { opcat_shift }
           ast::eq { opcat_eq }
           ast::ne { opcat_eq }
           ast::lt { opcat_rel }

src/rustc/middle/typeck/check.rs

@@ -867,8 +867,8 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
     fn binop_method(op: ast::binop) -> option<str> {
         alt op {
           ast::add | ast::subtract | ast::mul | ast::div | ast::rem |
-          ast::bitxor | ast::bitand | ast::bitor | ast::lsl | ast::lsr |
-          ast::asr { some(ast_util::binop_to_str(op)) }
+          ast::bitxor | ast::bitand | ast::bitor | ast::shl | ast::shr
+          { some(ast_util::binop_to_str(op)) }
           _ { none }
         }
     }

src/test/run-pass/binops.rs

@@ -47,7 +47,6 @@ fn test_char() {
     assert (ch10 / ch4 == ch2);
     assert (ch10 % ch4 == ch2);
     assert (ch10 >> ch2 == ch2);
-    assert (ch10 >>> ch2 == ch2);
     assert (ch10 << ch4 == 160 as char);
     assert (ch10 | ch4 == 14 as char);
     assert (ch10 & ch2 == ch2);

src/test/run-pass/bitwise.rs

@@ -2,12 +2,12 @@
 
 #[cfg(target_arch = "x86")]
 fn target() {
-    assert (-1000 >> 3 == 536870787);
+    assert (-1000 as uint >> 3u == 536870787u);
 }
 
 #[cfg(target_arch = "x86_64")]
 fn target() {
-    assert (-1000 >> 3 == 2305843009213693827);
+    assert (-1000 as uint >> 3u == 2305843009213693827u);
 }
 
 fn general() {
@@ -24,7 +24,7 @@ fn general() {
     assert (0xf0 | 0xf == 0xff);
     assert (0xf << 4 == 0xf0);
     assert (0xf0 >> 4 == 0xf);
-    assert (-16 >>> 2 == -4);
+    assert (-16 >> 2 == -4);
     assert (0b1010_1010 | 0b0101_0101 == 0xff);
 }
 

src/test/run-pass/shift.rs

@@ -16,71 +16,56 @@ fn test_expr() {
     let v4 = 4 as u8;
     let v2 = 2 as u8;
     assert (v10 >> v2 == v2 as uint);
-    assert (v10 >>> v2 == v2 as uint);
     assert (v10 << v4 == 160 as uint);
 
     let v10 = 10 as u8;
     let v4 = 4 as uint;
     let v2 = 2 as uint;
     assert (v10 >> v2 == v2 as u8);
-    assert (v10 >>> v2 == v2 as u8);
     assert (v10 << v4 == 160 as u8);
 
     let v10 = 10 as int;
     let v4 = 4 as i8;
     let v2 = 2 as i8;
     assert (v10 >> v2 == v2 as int);
-    assert (v10 >>> v2 == v2 as int);
     assert (v10 << v4 == 160 as int);
 
     let v10 = 10 as i8;
     let v4 = 4 as int;
     let v2 = 2 as int;
     assert (v10 >> v2 == v2 as i8);
-    assert (v10 >>> v2 == v2 as i8);
     assert (v10 << v4 == 160 as i8);
 
     let v10 = 10 as uint;
     let v4 = 4 as int;
     let v2 = 2 as int;
     assert (v10 >> v2 == v2 as uint);
-    assert (v10 >>> v2 == v2 as uint);
     assert (v10 << v4 == 160 as uint);
 }
 
 fn test_const() {
     const r1_1: uint = 10u >> 2u8;
-    const r2_1: uint = 10u >>> 2u8;
-    const r3_1: uint = 10u << 4u8;
+    const r2_1: uint = 10u << 4u8;
     assert r1_1 == 2 as uint;
-    assert r2_1 == 2 as uint;
-    assert r3_1 == 160 as uint;
+    assert r2_1 == 160 as uint;
 
     const r1_2: u8 = 10u8 >> 2u;
-    const r2_2: u8 = 10u8 >>> 2u;
-    const r3_2: u8 = 10u8 << 4u;
+    const r2_2: u8 = 10u8 << 4u;
     assert r1_2 == 2 as u8;
-    assert r2_2 == 2 as u8;
-    assert r3_2 == 160 as u8;
+    assert r2_2 == 160 as u8;
 
     const r1_3: int = 10 >> 2i8;
-    const r2_3: int = 10 >>> 2i8;
-    const r3_3: int = 10 << 4i8;
+    const r2_3: int = 10 << 4i8;
     assert r1_3 == 2 as int;
-    assert r2_3 == 2 as int;
-    assert r3_3 == 160 as int;
+    assert r2_3 == 160 as int;
 
     const r1_4: i8 = 10i8 >> 2;
-    const r2_4: i8 = 10i8 >>> 2;
-    const r3_4: i8 = 10i8 << 4;
+    const r2_4: i8 = 10i8 << 4;
     assert r1_4 == 2 as i8;
-    assert r2_4 == 2 as i8;
-    assert r3_4 == 160 as i8;
+    assert r2_4 == 160 as i8;
 
     const r1_5: uint = 10u >> 2i8;
-    const r2_5: uint = 10u >>> 2i8;
-    const r3_5: uint = 10u << 4i8;
+    const r2_5: uint = 10u << 4i8;
     assert r1_5 == 2 as uint;
-    assert r2_5 == 2 as uint;
-    assert r3_5 == 160 as uint;
+    assert r2_5 == 160 as uint;
 }