diff options
Diffstat (limited to 'yjit/src/codegen.rs')
| -rw-r--r-- | yjit/src/codegen.rs | 41 |
1 files changed, 27 insertions, 14 deletions
diff --git a/yjit/src/codegen.rs b/yjit/src/codegen.rs index 1baa5edd64..3af6167045 100644 --- a/yjit/src/codegen.rs +++ b/yjit/src/codegen.rs @@ -4471,7 +4471,6 @@ fn jit_rb_int_div( true } -/* fn jit_rb_int_lshift( jit: &mut JITState, asm: &mut Assembler, @@ -4487,28 +4486,42 @@ fn jit_rb_int_lshift( } guard_two_fixnums(jit, asm, ocb); + let comptime_shift = jit.peek_at_stack(&asm.ctx, 0); + + if !comptime_shift.fixnum_p() { + return false; + } + + // Untag the fixnum shift amount + let shift_amt = comptime_shift.as_isize() >> 1; + + if shift_amt > 63 || shift_amt < 0 { + return false; + } + let rhs = asm.stack_pop(1); let lhs = asm.stack_pop(1); - // Ruby supports using a negative shift value - asm.comment("Guard shift negative"); - let shift_val = asm.sub(rhs, 1.into()); - asm.cmp(shift_val, 0.into()); - asm.jl(Target::side_exit(Counter::lshift_range)); + // Guard on the shift value we speculated on + asm.cmp(rhs, comptime_shift.into()); + asm.jne(Target::side_exit(Counter::lshift_amt_changed)); + + let in_val = asm.sub(lhs, 1.into()); + let shift_opnd = Opnd::UImm(shift_amt as u64); + let out_val = asm.lshift(in_val, shift_opnd); + let unshifted = asm.rshift(out_val, shift_opnd); - asm.cmp(shift_val, 63.into()); - asm.jg(Target::side_exit(Counter::lshift_range)); + // Guard that we did not overflow + asm.cmp(unshifted, in_val); + asm.jne(Target::side_exit(Counter::lshift_overflow)); - // FIXME: we don't yet support shift with non-immediate values in the backend - // Do the shifting - let out_val = asm.lshift(lhs, shift_val); - asm.jo(Target::side_exit(Counter::lshift_overflow)); + // Re-tag the output value + let out_val = asm.add(out_val, 1.into()); let ret_opnd = asm.stack_push(Type::Fixnum); asm.mov(ret_opnd, out_val); true } -*/ fn jit_rb_int_aref( jit: &mut JITState, @@ -8593,7 +8606,7 @@ impl CodegenGlobals { self.yjit_reg_method(rb_cInteger, "*", jit_rb_int_mul); self.yjit_reg_method(rb_cInteger, "/", jit_rb_int_div); - //self.yjit_reg_method(rb_cInteger, "<<", jit_rb_int_lshift); + self.yjit_reg_method(rb_cInteger, "<<", jit_rb_int_lshift); self.yjit_reg_method(rb_cInteger, "[]", jit_rb_int_aref); // rb_str_to_s() methods in string.c |