rustc: track validity ranges for layout::Abi::Scalar values.

eddyb · eddyb · commit f62e43da2891 · 2017-11-19T02:14:33.000+02:00
diff --git a/src/librustc/ty/layout.rs b/src/librustc/ty/layout.rs
diff --git a/src/librustc_lint/types.rs b/src/librustc_lint/types.rs
@@ -753,8 +753,8 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for VariantSizeDifferences {
                     bug!("failed to get layout for `{}`: {}", t, e)
                 });
 
-                if let layout::Variants::Tagged { ref variants, discr, .. } = layout.variants {
-                    let discr_size = discr.size(cx.tcx).bytes();
+                if let layout::Variants::Tagged { ref variants, ref discr, .. } = layout.variants {
+                    let discr_size = discr.value.size(cx.tcx).bytes();
 
                     debug!("enum `{}` is {} bytes large with layout:\n{:#?}",
                       t, layout.size.bytes(), layout);
diff --git a/src/librustc_trans/abi.rs b/src/librustc_trans/abi.rs
@@ -287,8 +287,8 @@ impl<'tcx> LayoutExt<'tcx> for TyLayout<'tcx> {
     fn homogeneous_aggregate<'a>(&self, ccx: &CrateContext<'a, 'tcx>) -> Option<Reg> {
         match self.abi {
             // The primitive for this algorithm.
-            layout::Abi::Scalar(value) => {
-                let kind = match value {
+            layout::Abi::Scalar(ref scalar) => {
+                let kind = match scalar.value {
                     layout::Int(..) |
                     layout::Pointer => RegKind::Integer,
                     layout::F32 |
@@ -471,8 +471,8 @@ impl<'a, 'tcx> ArgType<'tcx> {
 
     pub fn extend_integer_width_to(&mut self, bits: u64) {
         // Only integers have signedness
-        match self.layout.abi {
-            layout::Abi::Scalar(layout::Int(i, signed)) => {
+        if let layout::Abi::Scalar(ref scalar) = self.layout.abi {
+            if let layout::Int(i, signed) = scalar.value {
                 if i.size().bits() < bits {
                     self.attrs.set(if signed {
                         ArgAttribute::SExt
@@ -481,8 +481,6 @@ impl<'a, 'tcx> ArgType<'tcx> {
                     });
                 }
             }
-
-            _ => {}
         }
     }
 
@@ -695,9 +693,12 @@ impl<'a, 'tcx> FnType<'tcx> {
 
         let arg_of = |ty: Ty<'tcx>, is_return: bool| {
             let mut arg = ArgType::new(ccx.layout_of(ty));
-            if let layout::Abi::Scalar(layout::Int(layout::I1, _)) = arg.layout.abi {
-                arg.attrs.set(ArgAttribute::ZExt);
-            } else if arg.layout.is_zst() {
+            if let layout::Abi::Scalar(ref scalar) = arg.layout.abi {
+                if scalar.is_bool() {
+                    arg.attrs.set(ArgAttribute::ZExt);
+                }
+            }
+            if arg.layout.is_zst() {
                 // For some forsaken reason, x86_64-pc-windows-gnu
                 // doesn't ignore zero-sized struct arguments.
                 // The same is true for s390x-unknown-linux-gnu.
diff --git a/src/librustc_trans/base.rs b/src/librustc_trans/base.rs
@@ -375,11 +375,12 @@ pub fn from_immediate(bcx: &Builder, val: ValueRef) -> ValueRef {
 }
 
 pub fn to_immediate(bcx: &Builder, val: ValueRef, layout: layout::TyLayout) -> ValueRef {
-    if let layout::Abi::Scalar(layout::Int(layout::I1, _)) = layout.abi {
-        bcx.trunc(val, Type::i1(bcx.ccx))
-    } else {
-        val
+    if let layout::Abi::Scalar(ref scalar) = layout.abi {
+        if scalar.is_bool() {
+            return bcx.trunc(val, Type::i1(bcx.ccx));
+        }
     }
+    val
 }
 
 pub fn call_memcpy(b: &Builder,
diff --git a/src/librustc_trans/cabi_s390x.rs b/src/librustc_trans/cabi_s390x.rs
@@ -27,8 +27,12 @@ fn classify_ret_ty(ret: &mut ArgType) {
 fn is_single_fp_element<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
                                   layout: TyLayout<'tcx>) -> bool {
     match layout.abi {
-        layout::Abi::Scalar(layout::F32) |
-        layout::Abi::Scalar(layout::F64) => true,
+        layout::Abi::Scalar(ref scalar) => {
+            match scalar.value {
+                layout::F32 | layout::F64 => true,
+                _ => false
+            }
+        }
         layout::Abi::Aggregate { .. } => {
             if layout.fields.count() == 1 && layout.fields.offset(0).bytes() == 0 {
                 is_single_fp_element(ccx, layout.field(ccx, 0))
diff --git a/src/librustc_trans/cabi_x86.rs b/src/librustc_trans/cabi_x86.rs
@@ -22,8 +22,12 @@ pub enum Flavor {
 fn is_single_fp_element<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
                                   layout: TyLayout<'tcx>) -> bool {
     match layout.abi {
-        layout::Abi::Scalar(layout::F32) |
-        layout::Abi::Scalar(layout::F64) => true,
+        layout::Abi::Scalar(ref scalar) => {
+            match scalar.value {
+                layout::F32 | layout::F64 => true,
+                _ => false
+            }
+        }
         layout::Abi::Aggregate { .. } => {
             if layout.fields.count() == 1 && layout.fields.offset(0).bytes() == 0 {
                 is_single_fp_element(ccx, layout.field(ccx, 0))
diff --git a/src/librustc_trans/cabi_x86_64.rs b/src/librustc_trans/cabi_x86_64.rs
@@ -65,8 +65,8 @@ fn classify_arg<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, arg: &ArgType<'tcx>)
         }
 
         match layout.abi {
-            layout::Abi::Scalar(value) => {
-                let reg = match value {
+            layout::Abi::Scalar(ref scalar) => {
+                let reg = match scalar.value {
                     layout::Int(..) |
                     layout::Pointer => Class::Int,
                     layout::F32 |
diff --git a/src/librustc_trans/debuginfo/metadata.rs b/src/librustc_trans/debuginfo/metadata.rs
@@ -1429,11 +1429,13 @@ fn prepare_enum_metadata<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
     let discriminant_type_metadata = match layout.variants {
         layout::Variants::Single { .. } |
         layout::Variants::NicheFilling { .. } => None,
-        layout::Variants::Tagged { discr, .. } => Some(discriminant_type_metadata(discr)),
+        layout::Variants::Tagged { ref discr, .. } => {
+            Some(discriminant_type_metadata(discr.value))
+        }
     };
 
-    match (layout.abi, discriminant_type_metadata) {
-        (layout::Abi::Scalar(_), Some(discr)) => return FinalMetadata(discr),
+    match (&layout.abi, discriminant_type_metadata) {
+        (&layout::Abi::Scalar(_), Some(discr)) => return FinalMetadata(discr),
         _ => {}
     }
 
diff --git a/src/librustc_trans/lib.rs b/src/librustc_trans/lib.rs
@@ -26,6 +26,7 @@
 #![feature(i128_type)]
 #![feature(i128)]
 #![feature(inclusive_range)]
+#![feature(inclusive_range_syntax)]
 #![feature(libc)]
 #![feature(quote)]
 #![feature(rustc_diagnostic_macros)]
diff --git a/src/librustc_trans/mir/block.rs b/src/librustc_trans/mir/block.rs
@@ -671,10 +671,17 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                                  (align | Alignment::Packed(arg.layout.align))
                                     .non_abi());
             } else {
+                // We can't use `LvalueRef::load` here because the argument
+                // may have a type we don't treat as immediate, but the ABI
+                // used for this call is passing it by-value. In that case,
+                // the load would just produce `OperandValue::Ref` instead
+                // of the `OperandValue::Immediate` we need for the call.
                 llval = bcx.load(llval, align.non_abi());
-            }
-            if let layout::Abi::Scalar(layout::Int(layout::I1, _)) = arg.layout.abi {
-                bcx.range_metadata(llval, 0..2);
+                if let layout::Abi::Scalar(ref scalar) = arg.layout.abi {
+                    if scalar.is_bool() {
+                        bcx.range_metadata(llval, 0..2);
+                    }
+                }
                 // We store bools as i8 so we need to truncate to i1.
                 llval = base::to_immediate(bcx, llval, arg.layout);
             }
diff --git a/src/librustc_trans/mir/constant.rs b/src/librustc_trans/mir/constant.rs
@@ -455,9 +455,9 @@ impl<'a, 'tcx> MirConstContext<'a, 'tcx> {
                                           Value(base));
                             }
                             let layout = self.ccx.layout_of(projected_ty);
-                            if let layout::Abi::Scalar(layout::Int(layout::I1, _)) = layout.abi {
+                            if let layout::Abi::Scalar(ref scalar) = layout.abi {
                                 let i1_type = Type::i1(self.ccx);
-                                if val_ty(val) != i1_type {
+                                if scalar.is_bool() && val_ty(val) != i1_type {
                                     unsafe {
                                         val = llvm::LLVMConstTrunc(val, i1_type.to_ref());
                                     }
@@ -685,10 +685,14 @@ impl<'a, 'tcx> MirConstContext<'a, 'tcx> {
                         assert!(cast_layout.is_llvm_immediate());
                         let ll_t_out = cast_layout.immediate_llvm_type(self.ccx);
                         let llval = operand.llval;
-                        let signed = match self.ccx.layout_of(operand.ty).abi {
-                            layout::Abi::Scalar(layout::Int(_, signed)) => signed,
-                            _ => false
-                        };
+
+                        let mut signed = false;
+                        let l = self.ccx.layout_of(operand.ty);
+                        if let layout::Abi::Scalar(ref scalar) = l.abi {
+                            if let layout::Int(_, true) = scalar.value {
+                                signed = true;
+                            }
+                        }
 
                         unsafe {
                             match (r_t_in, r_t_out) {
diff --git a/src/librustc_trans/mir/lvalue.rs b/src/librustc_trans/mir/lvalue.rs
@@ -148,16 +148,29 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
                 const_llval
             } else {
                 let load = bcx.load(self.llval, self.alignment.non_abi());
-                if self.layout.ty.is_bool() {
-                    bcx.range_metadata(load, 0..2);
-                } else if self.layout.ty.is_char() {
-                    // a char is a Unicode codepoint, and so takes values from 0
-                    // to 0x10FFFF inclusive only.
-                    bcx.range_metadata(load, 0..0x10FFFF+1);
-                } else if self.layout.ty.is_region_ptr() ||
-                        self.layout.ty.is_box() ||
-                        self.layout.ty.is_fn() {
-                    bcx.nonnull_metadata(load);
+                if let layout::Abi::Scalar(ref scalar) = self.layout.abi {
+                    let (min, max) = (scalar.valid_range.start, scalar.valid_range.end);
+                    let max_next = max.wrapping_add(1);
+                    let bits = scalar.value.size(bcx.ccx).bits();
+                    assert!(bits <= 128);
+                    let mask = !0u128 >> (128 - bits);
+                    // For a (max) value of -1, max will be `-1 as usize`, which overflows.
+                    // However, that is fine here (it would still represent the full range),
+                    // i.e., if the range is everything.  The lo==hi case would be
+                    // rejected by the LLVM verifier (it would mean either an
+                    // empty set, which is impossible, or the entire range of the
+                    // type, which is pointless).
+                    match scalar.value {
+                        layout::Int(..) if max_next & mask != min & mask => {
+                            // llvm::ConstantRange can deal with ranges that wrap around,
+                            // so an overflow on (max + 1) is fine.
+                            bcx.range_metadata(load, min..max_next);
+                        }
+                        layout::Pointer if 0 < min && min < max => {
+                            bcx.nonnull_metadata(load);
+                        }
+                        _ => {}
+                    }
                 }
                 load
             };
@@ -274,48 +287,18 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
         let cast_to = bcx.ccx.layout_of(cast_to).immediate_llvm_type(bcx.ccx);
         match self.layout.variants {
             layout::Variants::Single { index } => {
-                assert_eq!(index, 0);
-                return C_uint(cast_to, 0);
+                return C_uint(cast_to, index as u64);
             }
             layout::Variants::Tagged { .. } |
             layout::Variants::NicheFilling { .. } => {},
         }
 
         let discr = self.project_field(bcx, 0);
-        let discr_scalar = match discr.layout.abi {
-            layout::Abi::Scalar(discr) => discr,
-            _ => bug!("discriminant not scalar: {:#?}", discr.layout)
-        };
-        let (min, max) = match self.layout.variants {
-            layout::Variants::Tagged { ref discr_range, .. } => {
-                (discr_range.start, discr_range.end)
-            }
-            _ => (0, !0),
-        };
-        let max_next = max.wrapping_add(1);
-        let bits = discr_scalar.size(bcx.ccx).bits();
-        assert!(bits <= 128);
-        let mask = !0u128 >> (128 - bits);
-        let lldiscr = bcx.load(discr.llval, discr.alignment.non_abi());
-        match discr_scalar {
-            // For a (max) discr of -1, max will be `-1 as usize`, which overflows.
-            // However, that is fine here (it would still represent the full range),
-            layout::Int(..) if max_next & mask != min & mask => {
-                // llvm::ConstantRange can deal with ranges that wrap around,
-                // so an overflow on (max + 1) is fine.
-                bcx.range_metadata(lldiscr, min..max_next);
-            }
-            _ => {
-                // i.e., if the range is everything.  The lo==hi case would be
-                // rejected by the LLVM verifier (it would mean either an
-                // empty set, which is impossible, or the entire range of the
-                // type, which is pointless).
-            }
-        };
+        let lldiscr = discr.load(bcx).immediate();
         match self.layout.variants {
             layout::Variants::Single { .. } => bug!(),
-            layout::Variants::Tagged { .. } => {
-                let signed = match discr_scalar {
+            layout::Variants::Tagged { ref discr, .. } => {
+                let signed = match discr.value {
                     layout::Int(_, signed) => signed,
                     _ => false
                 };
diff --git a/src/librustc_trans/mir/rvalue.rs b/src/librustc_trans/mir/rvalue.rs
@@ -119,6 +119,7 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                     }
 
                     // Use llvm.memset.p0i8.* to initialize byte arrays
+                    let v = base::from_immediate(&bcx, v);
                     if common::val_ty(v) == Type::i8(bcx.ccx) {
                         base::call_memset(&bcx, start, v, size, align, false);
                         return bcx;
@@ -278,28 +279,25 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                         let ll_t_out = cast.immediate_llvm_type(bcx.ccx);
                         let llval = operand.immediate();
 
-                        match operand.layout.variants {
-                            layout::Variants::Tagged {
-                                ref discr_range, ..
-                            } if discr_range.end > discr_range.start => {
-                                // We want `table[e as usize]` to not
-                                // have bound checks, and this is the most
-                                // convenient place to put the `assume`.
-
-                                base::call_assume(&bcx, bcx.icmp(
-                                    llvm::IntULE,
-                                    llval,
-                                    C_uint_big(ll_t_in, discr_range.end)
-                                ));
+                        let mut signed = false;
+                        if let layout::Abi::Scalar(ref scalar) = operand.layout.abi {
+                            if let layout::Int(_, s) = scalar.value {
+                                signed = s;
+
+                                if scalar.valid_range.end > scalar.valid_range.start {
+                                    // We want `table[e as usize]` to not
+                                    // have bound checks, and this is the most
+                                    // convenient place to put the `assume`.
+
+                                    base::call_assume(&bcx, bcx.icmp(
+                                        llvm::IntULE,
+                                        llval,
+                                        C_uint_big(ll_t_in, scalar.valid_range.end)
+                                    ));
+                                }
                             }
-                            _ => {}
                         }
 
-                        let signed = match operand.layout.abi {
-                            layout::Abi::Scalar(layout::Int(_, signed)) => signed,
-                            _ => false
-                        };
-
                         let newval = match (r_t_in, r_t_out) {
                             (CastTy::Int(_), CastTy::Int(_)) => {
                                 bcx.intcast(llval, ll_t_out, signed)
diff --git a/src/librustc_trans/type_.rs b/src/librustc_trans/type_.rs
@@ -268,7 +268,6 @@ impl Type {
     pub fn from_integer(cx: &CrateContext, i: layout::Integer) -> Type {
         use rustc::ty::layout::Integer::*;
         match i {
-            I1 => Type::i1(cx),
             I8 => Type::i8(cx),
             I16 => Type::i16(cx),
             I32 => Type::i32(cx),
diff --git a/src/librustc_trans/type_of.rs b/src/librustc_trans/type_of.rs
@@ -176,14 +176,13 @@ impl<'tcx> LayoutLlvmExt<'tcx> for TyLayout<'tcx> {
     /// of that field's type - this is useful for taking the address of
     /// that field and ensuring the struct has the right alignment.
     fn llvm_type<'a>(&self, ccx: &CrateContext<'a, 'tcx>) -> Type {
-        if let layout::Abi::Scalar(value) = self.abi {
+        if let layout::Abi::Scalar(ref scalar) = self.abi {
             // Use a different cache for scalars because pointers to DSTs
             // can be either fat or thin (data pointers of fat pointers).
             if let Some(&llty) = ccx.scalar_lltypes().borrow().get(&self.ty) {
                 return llty;
             }
-            let llty = match value {
-                layout::Int(layout::I1, _) => Type::i8(ccx),
+            let llty = match scalar.value {
                 layout::Int(i, _) => Type::from_integer(ccx, i),
                 layout::F32 => Type::f32(ccx),
                 layout::F64 => Type::f64(ccx),
@@ -249,11 +248,12 @@ impl<'tcx> LayoutLlvmExt<'tcx> for TyLayout<'tcx> {
     }
 
     fn immediate_llvm_type<'a>(&self, ccx: &CrateContext<'a, 'tcx>) -> Type {
-        if let layout::Abi::Scalar(layout::Int(layout::I1, _)) = self.abi {
-            Type::i1(ccx)
-        } else {
-            self.llvm_type(ccx)
+        if let layout::Abi::Scalar(ref scalar) = self.abi {
+            if scalar.is_bool() {
+                return Type::i1(ccx);
+            }
         }
+        self.llvm_type(ccx)
     }
 
     fn over_align(&self) -> Option<Align> {

Original file line number	Diff line number	Diff line change
`@@ -375,11 +375,12 @@ pub fn from_immediate(bcx: &Builder, val: ValueRef) -> ValueRef {`
`375`	`375`	`}`
`376`	`376`
`377`	`377`	`pub fn to_immediate(bcx: &Builder, val: ValueRef, layout: layout::TyLayout) -> ValueRef {`
`378`		`- if let layout::Abi::Scalar(layout::Int(layout::I1, _)) = layout.abi {`
`379`		`- bcx.trunc(val, Type::i1(bcx.ccx))`
`380`		`- } else {`
`381`		`- val`
	`378`	`+ if let layout::Abi::Scalar(ref scalar) = layout.abi {`
	`379`	`+ if scalar.is_bool() {`
	`380`	`+ return bcx.trunc(val, Type::i1(bcx.ccx));`
	`381`	`+ }`
`382`	`382`	`}`
	`383`	`+ val`
`383`	`384`	`}`
`384`	`385`
`385`	`386`	`pub fn call_memcpy(b: &Builder,`