zig

commit 0543def52f5ec2d76dc415da2546e478af491ac3 (tree)
parent ff97bd21c3b6a5079f33ff389da0716a12806e29
Author: Jacob Young <jacobly0@users.noreply.github.com>
Date:   Wed, 29 Mar 2023 21:22:14 -0400

llvm: fix crashes when loading a struct field

The result of buildStructGEP is not always a GEP (sorry), so we can't
use getGEPResultElementType on it.

Closes #14641

Diffstat:
M
src/codegen/llvm.zig
 | 
6
+++---
M
src/codegen/llvm/bindings.zig
 | 
3
---
M
src/zig_llvm.cpp
 | 
4
----
M
src/zig_llvm.h
 | 
2
--
M
test/behavior/union.zig
 | 
11
+++++++++++

5 files changed, 14 insertions(+), 12 deletions(-)
diff --git a/src/codegen/llvm.zig b/src/codegen/llvm.zig
@@ -5558,7 +5558,7 @@ pub const FuncGen = struct {
 
                 return fg.loadByRef(payload_ptr, payload_ty, payload_ty.abiAlignment(target), false);
             }
-            const load_inst = fg.builder.buildLoad(payload_ptr.getGEPResultElementType(), payload_ptr, "");
+            const load_inst = fg.builder.buildLoad(err_union_llvm_ty.structGetTypeAtIndex(offset), payload_ptr, "");
             load_inst.setAlignment(payload_ty.abiAlignment(target));
             return load_inst;
         }
@@ -6792,7 +6792,7 @@ pub const FuncGen = struct {
 
                 return self.loadByRef(payload_ptr, payload_ty, payload_ty.abiAlignment(target), false);
             }
-            const load_inst = self.builder.buildLoad(payload_ptr.getGEPResultElementType(), payload_ptr, "");
+            const load_inst = self.builder.buildLoad(err_union_llvm_ty.structGetTypeAtIndex(offset), payload_ptr, "");
             load_inst.setAlignment(payload_ty.abiAlignment(target));
             return load_inst;
         }
@@ -8580,7 +8580,7 @@ pub const FuncGen = struct {
             }
             const tag_index = @boolToInt(layout.tag_align < layout.payload_align);
             const tag_field_ptr = self.builder.buildStructGEP(llvm_un_ty, union_handle, tag_index, "");
-            return self.builder.buildLoad(tag_field_ptr.getGEPResultElementType(), tag_field_ptr, "");
+            return self.builder.buildLoad(llvm_un_ty.structGetTypeAtIndex(tag_index), tag_field_ptr, "");
         } else {
             if (layout.payload_size == 0) {
                 return union_handle;
diff --git a/src/codegen/llvm/bindings.zig b/src/codegen/llvm/bindings.zig
@@ -254,9 +254,6 @@ pub const Value = opaque {
     pub const addFunctionAttr = ZigLLVMAddFunctionAttr;
     extern fn ZigLLVMAddFunctionAttr(Fn: *Value, attr_name: [*:0]const u8, attr_value: [*:0]const u8) void;
 
-    pub const getGEPResultElementType = ZigLLVMGetGEPResultElementType;
-    extern fn ZigLLVMGetGEPResultElementType(GEP: *Value) *Type;
-
     pub const addByValAttr = ZigLLVMAddByValAttr;
     extern fn ZigLLVMAddByValAttr(Fn: *Value, ArgNo: c_uint, type: *Type) void;
 };
diff --git a/src/zig_llvm.cpp b/src/zig_llvm.cpp
@@ -1239,10 +1239,6 @@ void ZigLLVMSetCallElemTypeAttr(LLVMValueRef Call, size_t arg_index, LLVMTypeRef
             Attribute::get(call_inst->getContext(), Attribute::ElementType, llvm_type));
 }
 
-LLVMTypeRef ZigLLVMGetGEPResultElementType(LLVMValueRef GEP) {
-    return wrap(unwrap<GEPOperator>(GEP)->getResultElementType());
-}
-
 void ZigLLVMFunctionSetPrefixData(LLVMValueRef function, LLVMValueRef data) {
     unwrap<Function>(function)->setPrefixData(unwrap<Constant>(data));
 }
diff --git a/src/zig_llvm.h b/src/zig_llvm.h
@@ -332,8 +332,6 @@ ZIG_EXTERN_C void ZigLLVMAddSretAttr(LLVMValueRef fn_ref, LLVMTypeRef type_val);
 ZIG_EXTERN_C void ZigLLVMAddFunctionElemTypeAttr(LLVMValueRef fn_ref, size_t arg_index, LLVMTypeRef elem_ty);
 ZIG_EXTERN_C void ZigLLVMAddFunctionAttrCold(LLVMValueRef fn);
 
-ZIG_EXTERN_C LLVMTypeRef ZigLLVMGetGEPResultElementType(LLVMValueRef GEP);
-
 ZIG_EXTERN_C void ZigLLVMParseCommandLineOptions(size_t argc, const char *const *argv);
 
 
diff --git a/test/behavior/union.zig b/test/behavior/union.zig
@@ -1529,3 +1529,14 @@ test "reinterpreting enum value inside packed union" {
     try U.doTest();
     comptime try U.doTest();
 }
+
+test "access the tag of a global tagged union" {
+    if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
+
+    const U = union(enum) {
+        a,
+        b: u8,
+        var u: @This() = .a;
+    };
+    try expect(U.u == .a);
+}