Commit 1ae2002b415614935746946c511e8093a1de2902 | zig

author	Andrew Kelley <andrew@ziglang.org> 2017-05-29 14:25:00-04:00
committer	Andrew Kelley <andrew@ziglang.org> 2017-05-29 14:25:00-04:00
log	1ae2002b415614935746946c511e8093a1de2902
tree	057dbef0709d65c9b6bfc7c1cbf50e19a54b9e25
parent	8ae4ffa49357a4939985884285fef39e86f5f705

fix crash when writing to const hardcoded ptr

closes #381

2 files changed, 19 insertions(+), 2 deletions(-)

src
- ir.cpp
test
- cases
  - misc.zig

src/ir.cpp+11-2

 @@ -9913,8 +9913,8 @@ static TypeTableEntry *ir_analyze_instruction_elem_ptr(IrAnalyze *ira, IrInstruc
             (array_type->id != TypeTableEntryIdPointer ||
                 array_ptr_val->data.x_ptr.special != ConstPtrSpecialHardCodedAddr))
         {
-            ConstExprValue *out_val = ir_build_const_from(ira, &elem_ptr_instruction->base);
             if (array_type->id == TypeTableEntryIdPointer) {
+                ConstExprValue *out_val = ir_build_const_from(ira, &elem_ptr_instruction->base);
                 out_val->data.x_ptr.mut = array_ptr_val->data.x_ptr.mut;
                 size_t new_index;
                 size_t mem_size;
 @@ -9959,9 +9959,16 @@ static TypeTableEntry *ir_analyze_instruction_elem_ptr(IrAnalyze *ira, IrInstruc
                         buf_sprintf("index %" ZIG_PRI_u64 " outside pointer of size %" ZIG_PRI_usize "", index, old_size));
                     return ira->codegen->builtin_types.entry_invalid;
                 }
+                return return_type;
             } else if (is_slice(array_type)) {
                 ConstExprValue *ptr_field = &array_ptr_val->data.x_struct.fields[slice_ptr_index];
+                if (ptr_field->data.x_ptr.special == ConstPtrSpecialHardCodedAddr) {
+                    ir_build_elem_ptr_from(&ira->new_irb, &elem_ptr_instruction->base, array_ptr,
+                            casted_elem_index, false);
+                    return return_type;
+                }
                 ConstExprValue *len_field = &array_ptr_val->data.x_struct.fields[slice_len_index];
+                ConstExprValue *out_val = ir_build_const_from(ira, &elem_ptr_instruction->base);
                 uint64_t slice_len = len_field->data.x_bignum.data.x_uint;
                 if (index >= slice_len) {
                     ir_add_error_node(ira, elem_ptr_instruction->base.source_node,
 @@ -9996,15 +10003,17 @@ static TypeTableEntry *ir_analyze_instruction_elem_ptr(IrAnalyze *ira, IrInstruc
                     case ConstPtrSpecialHardCodedAddr:
                         zig_unreachable();
                 }
+                return return_type;
             } else if (array_type->id == TypeTableEntryIdArray) {
+                ConstExprValue *out_val = ir_build_const_from(ira, &elem_ptr_instruction->base);
                 out_val->data.x_ptr.special = ConstPtrSpecialBaseArray;
                 out_val->data.x_ptr.mut = array_ptr->value.data.x_ptr.mut;
                 out_val->data.x_ptr.data.base_array.array_val = array_ptr_val;
                 out_val->data.x_ptr.data.base_array.elem_index = index;
+                return return_type;
             } else {
                 zig_unreachable();
             }
-            return return_type;
         }
     }

test/cases/misc.zig+8

...	@@ -526,3 +526,11 @@ var gdt = []GDTEntry {	...	@@ -526,3 +526,11 @@ var gdt = []GDTEntry {
526	GDTEntry {.field = 2},	526	GDTEntry {.field = 2},
527	};	527	};
528	var global_ptr = &gdt[0];	528	var global_ptr = &gdt[0];
		529
		530
		531	// can't really run this test but we can make sure it has no compile error
		532	// and generates code
		533	const vram = @intToPtr(&volatile u8, 0x20000000)[0..0x8000];
		534	export fn writeToVRam() {
		535	vram[0] = 'X';
		536	}