From 89f6ff177178dba4e66680227a02de7b4068123c Mon Sep 17 00:00:00 2001
From: Veikka Tuominen <git@vexu.eu>
Date: Sat, 19 Feb 2022 15:24:22 +0200
Subject: stage2: correct use of .unwrap_err_union_* in LLVM and C backend

---
 src/codegen/c.zig | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

(limited to 'src/codegen/c.zig')

diff --git a/src/codegen/c.zig b/src/codegen/c.zig
index 776cec6457..f6e2d467a7 100644
--- a/src/codegen/c.zig
+++ b/src/codegen/c.zig
@@ -3090,17 +3090,18 @@ fn airUnwrapErrUnionErr(f: *Function, inst: Air.Inst.Index) !CValue {
     const operand = try f.resolveInst(ty_op.operand);
     const operand_ty = f.air.typeOf(ty_op.operand);
 
-    const payload_ty = operand_ty.errorUnionPayload();
-    if (!payload_ty.hasRuntimeBits()) {
-        if (operand_ty.zigTypeTag() == .Pointer) {
-            const local = try f.allocLocal(inst_ty, .Const);
-            try writer.writeAll(" = *");
-            try f.writeCValue(writer, operand);
-            try writer.writeAll(";\n");
-            return local;
-        } else {
+    if (operand_ty.zigTypeTag() == .Pointer) {
+        if (!operand_ty.childType().errorUnionPayload().hasRuntimeBits()) {
             return operand;
         }
+        const local = try f.allocLocal(inst_ty, .Const);
+        try writer.writeAll(" = *");
+        try f.writeCValue(writer, operand);
+        try writer.writeAll(";\n");
+        return local;
+    }
+    if (!operand_ty.errorUnionPayload().hasRuntimeBits()) {
+        return operand;
     }
 
     const local = try f.allocLocal(inst_ty, .Const);
@@ -3123,8 +3124,11 @@ fn airUnwrapErrUnionPay(f: *Function, inst: Air.Inst.Index, maybe_addrof: []cons
     const operand = try f.resolveInst(ty_op.operand);
     const operand_ty = f.air.typeOf(ty_op.operand);
 
-    const payload_ty = operand_ty.errorUnionPayload();
-    if (!payload_ty.hasRuntimeBits()) {
+    const error_union_ty = if (operand_ty.zigTypeTag() == .Pointer)
+        operand_ty.childType()
+    else
+        operand_ty;
+    if (!error_union_ty.errorUnionPayload().hasRuntimeBits()) {
         return CValue.none;
     }
 
-- 
cgit v1.2.3


From 27c63bf433f27b06bed92111cbc96e8574de8d11 Mon Sep 17 00:00:00 2001
From: Veikka Tuominen <git@vexu.eu>
Date: Sat, 19 Feb 2022 19:21:49 +0200
Subject: stage2: implement errunion_payload_ptr_set

---
 src/Air.zig                  |  4 ++++
 src/Liveness.zig             |  1 +
 src/Sema.zig                 |  8 +++++++-
 src/arch/aarch64/CodeGen.zig |  7 +++++++
 src/arch/arm/CodeGen.zig     |  7 +++++++
 src/arch/riscv64/CodeGen.zig |  7 +++++++
 src/arch/wasm/CodeGen.zig    |  1 +
 src/arch/x86_64/CodeGen.zig  | 10 ++++++++++
 src/codegen/c.zig            |  7 +++++++
 src/codegen/llvm.zig         | 32 ++++++++++++++++++++++++++++++++
 src/print_air.zig            |  1 +
 test/behavior.zig            |  2 +-
 12 files changed, 85 insertions(+), 2 deletions(-)

(limited to 'src/codegen/c.zig')

diff --git a/src/Air.zig b/src/Air.zig
index 070b43ac49..b9a565ad2e 100644
--- a/src/Air.zig
+++ b/src/Air.zig
@@ -429,6 +429,9 @@ pub const Inst = struct {
         /// *(E!T) -> E. If the value is not an error, undefined behavior.
         /// Uses the `ty_op` field.
         unwrap_errunion_err_ptr,
+        /// *(E!T) => *T. Sets the value to non-error with an undefined payload value.
+        /// Uses the `ty_op` field.
+        errunion_payload_ptr_set,
         /// wrap from T to E!T
         /// Uses the `ty_op` field.
         wrap_errunion_payload,
@@ -865,6 +868,7 @@ pub fn typeOfIndex(air: Air, inst: Air.Inst.Index) Type {
         .optional_payload,
         .optional_payload_ptr,
         .optional_payload_ptr_set,
+        .errunion_payload_ptr_set,
         .wrap_optional,
         .unwrap_errunion_payload,
         .unwrap_errunion_err,
diff --git a/src/Liveness.zig b/src/Liveness.zig
index 71f1221b23..5a329d2a7a 100644
--- a/src/Liveness.zig
+++ b/src/Liveness.zig
@@ -293,6 +293,7 @@ fn analyzeInst(
         .optional_payload,
         .optional_payload_ptr,
         .optional_payload_ptr_set,
+        .errunion_payload_ptr_set,
         .wrap_optional,
         .unwrap_errunion_payload,
         .unwrap_errunion_err,
diff --git a/src/Sema.zig b/src/Sema.zig
index acccc0e3bf..2d9381493a 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -1636,7 +1636,13 @@ fn zirCoerceResultPtr(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileE
                 return sema.fail(block, src, "TODO coerce_result_ptr wrap_errunion_err", .{});
             },
             .wrap_errunion_payload => {
-                return sema.fail(block, src, "TODO coerce_result_ptr wrap_errunion_payload", .{});
+                const ty_op = air_datas[trash_inst].ty_op;
+                const payload_ty = sema.getTmpAir().typeOf(ty_op.operand);
+                const ptr_payload_ty = try Type.ptr(sema.arena, .{
+                    .pointee_type = payload_ty,
+                    .@"addrspace" = addr_space,
+                });
+                new_ptr = try block.addTyOp(.errunion_payload_ptr_set, ptr_payload_ty, new_ptr);
             },
             else => {
                 if (std.debug.runtime_safety) {
diff --git a/src/arch/aarch64/CodeGen.zig b/src/arch/aarch64/CodeGen.zig
index 7a3d049ae6..2267a156f9 100644
--- a/src/arch/aarch64/CodeGen.zig
+++ b/src/arch/aarch64/CodeGen.zig
@@ -662,6 +662,7 @@ fn genBody(self: *Self, body: []const Air.Inst.Index) InnerError!void {
             .unwrap_errunion_payload    => try self.airUnwrapErrPayload(inst),
             .unwrap_errunion_err_ptr    => try self.airUnwrapErrErrPtr(inst),
             .unwrap_errunion_payload_ptr=> try self.airUnwrapErrPayloadPtr(inst),
+            .errunion_payload_ptr_set   => try self.airErrUnionPayloadPtrSet(inst),
 
             .wrap_optional         => try self.airWrapOptional(inst),
             .wrap_errunion_payload => try self.airWrapErrUnionPayload(inst),
@@ -1443,6 +1444,12 @@ fn airUnwrapErrPayloadPtr(self: *Self, inst: Air.Inst.Index) !void {
     return self.finishAir(inst, result, .{ ty_op.operand, .none, .none });
 }
 
+fn airErrUnionPayloadPtrSet(self: *Self, inst: Air.Inst.Index) !void {
+    const ty_op = self.air.instructions.items(.data)[inst].ty_op;
+    const result: MCValue = if (self.liveness.isUnused(inst)) .dead else return self.fail("TODO implement .errunion_payload_ptr_set for {}", .{self.target.cpu.arch});
+    return self.finishAir(inst, result, .{ ty_op.operand, .none, .none });
+}
+
 fn airWrapOptional(self: *Self, inst: Air.Inst.Index) !void {
     const ty_op = self.air.instructions.items(.data)[inst].ty_op;
     const result: MCValue = if (self.liveness.isUnused(inst)) .dead else result: {
diff --git a/src/arch/arm/CodeGen.zig b/src/arch/arm/CodeGen.zig
index 6f87c56503..3633b5ccd0 100644
--- a/src/arch/arm/CodeGen.zig
+++ b/src/arch/arm/CodeGen.zig
@@ -646,6 +646,7 @@ fn genBody(self: *Self, body: []const Air.Inst.Index) InnerError!void {
             .unwrap_errunion_payload    => try self.airUnwrapErrPayload(inst),
             .unwrap_errunion_err_ptr    => try self.airUnwrapErrErrPtr(inst),
             .unwrap_errunion_payload_ptr=> try self.airUnwrapErrPayloadPtr(inst),
+            .errunion_payload_ptr_set   => try self.airErrUnionPayloadPtrSet(inst),
 
             .wrap_optional         => try self.airWrapOptional(inst),
             .wrap_errunion_payload => try self.airWrapErrUnionPayload(inst),
@@ -1128,6 +1129,12 @@ fn airUnwrapErrPayloadPtr(self: *Self, inst: Air.Inst.Index) !void {
     return self.finishAir(inst, result, .{ ty_op.operand, .none, .none });
 }
 
+fn airErrUnionPayloadPtrSet(self: *Self, inst: Air.Inst.Index) !void {
+    const ty_op = self.air.instructions.items(.data)[inst].ty_op;
+    const result: MCValue = if (self.liveness.isUnused(inst)) .dead else return self.fail("TODO implement .errunion_payload_ptr_set for {}", .{self.target.cpu.arch});
+    return self.finishAir(inst, result, .{ ty_op.operand, .none, .none });
+}
+
 fn airWrapOptional(self: *Self, inst: Air.Inst.Index) !void {
     const ty_op = self.air.instructions.items(.data)[inst].ty_op;
     const result: MCValue = if (self.liveness.isUnused(inst)) .dead else result: {
diff --git a/src/arch/riscv64/CodeGen.zig b/src/arch/riscv64/CodeGen.zig
index d73e083dbc..10764ad6cd 100644
--- a/src/arch/riscv64/CodeGen.zig
+++ b/src/arch/riscv64/CodeGen.zig
@@ -633,6 +633,7 @@ fn genBody(self: *Self, body: []const Air.Inst.Index) InnerError!void {
             .unwrap_errunion_payload    => try self.airUnwrapErrPayload(inst),
             .unwrap_errunion_err_ptr    => try self.airUnwrapErrErrPtr(inst),
             .unwrap_errunion_payload_ptr=> try self.airUnwrapErrPayloadPtr(inst),
+            .errunion_payload_ptr_set   => try self.airErrUnionPayloadPtrSet(inst),
 
             .wrap_optional         => try self.airWrapOptional(inst),
             .wrap_errunion_payload => try self.airWrapErrUnionPayload(inst),
@@ -1065,6 +1066,12 @@ fn airUnwrapErrPayloadPtr(self: *Self, inst: Air.Inst.Index) !void {
     return self.finishAir(inst, result, .{ ty_op.operand, .none, .none });
 }
 
+fn airErrUnionPayloadPtrSet(self: *Self, inst: Air.Inst.Index) !void {
+    const ty_op = self.air.instructions.items(.data)[inst].ty_op;
+    const result: MCValue = if (self.liveness.isUnused(inst)) .dead else return self.fail("TODO implement .errunion_payload_ptr_set for {}", .{self.target.cpu.arch});
+    return self.finishAir(inst, result, .{ ty_op.operand, .none, .none });
+}
+
 fn airWrapOptional(self: *Self, inst: Air.Inst.Index) !void {
     const ty_op = self.air.instructions.items(.data)[inst].ty_op;
     const result: MCValue = if (self.liveness.isUnused(inst)) .dead else result: {
diff --git a/src/arch/wasm/CodeGen.zig b/src/arch/wasm/CodeGen.zig
index 2bd6b92963..b776f30346 100644
--- a/src/arch/wasm/CodeGen.zig
+++ b/src/arch/wasm/CodeGen.zig
@@ -1725,6 +1725,7 @@ fn genInst(self: *Self, inst: Air.Inst.Index) !WValue {
         .atomic_rmw,
         .tag_name,
         .error_name,
+        .errunion_payload_ptr_set,
 
         // For these 4, probably best to wait until https://github.com/ziglang/zig/issues/10248
         // is implemented in the frontend before implementing them here in the wasm backend.
diff --git a/src/arch/x86_64/CodeGen.zig b/src/arch/x86_64/CodeGen.zig
index 441af51de2..d7d6ac9da8 100644
--- a/src/arch/x86_64/CodeGen.zig
+++ b/src/arch/x86_64/CodeGen.zig
@@ -727,6 +727,7 @@ fn genBody(self: *Self, body: []const Air.Inst.Index) InnerError!void {
             .unwrap_errunion_payload    => try self.airUnwrapErrPayload(inst),
             .unwrap_errunion_err_ptr    => try self.airUnwrapErrErrPtr(inst),
             .unwrap_errunion_payload_ptr=> try self.airUnwrapErrPayloadPtr(inst),
+            .errunion_payload_ptr_set   => try self.airErrUnionPayloadPtrSet(inst),
 
             .wrap_optional         => try self.airWrapOptional(inst),
             .wrap_errunion_payload => try self.airWrapErrUnionPayload(inst),
@@ -1406,6 +1407,15 @@ fn airUnwrapErrPayloadPtr(self: *Self, inst: Air.Inst.Index) !void {
     return self.finishAir(inst, result, .{ ty_op.operand, .none, .none });
 }
 
+fn airErrUnionPayloadPtrSet(self: *Self, inst: Air.Inst.Index) !void {
+    const ty_op = self.air.instructions.items(.data)[inst].ty_op;
+    const result: MCValue = if (self.liveness.isUnused(inst))
+        .dead
+    else
+        return self.fail("TODO implement .errunion_payload_ptr_set for {}", .{self.target.cpu.arch});
+    return self.finishAir(inst, result, .{ ty_op.operand, .none, .none });
+}
+
 fn airWrapOptional(self: *Self, inst: Air.Inst.Index) !void {
     const ty_op = self.air.instructions.items(.data)[inst].ty_op;
     const result: MCValue = if (self.liveness.isUnused(inst)) .dead else result: {
diff --git a/src/codegen/c.zig b/src/codegen/c.zig
index f6e2d467a7..fe0184849d 100644
--- a/src/codegen/c.zig
+++ b/src/codegen/c.zig
@@ -1753,6 +1753,7 @@ fn genBody(f: *Function, body: []const Air.Inst.Index) error{ AnalysisFail, OutO
             .unwrap_errunion_err_ptr     => try airUnwrapErrUnionErr(f, inst),
             .wrap_errunion_payload       => try airWrapErrUnionPay(f, inst),
             .wrap_errunion_err           => try airWrapErrUnionErr(f, inst),
+            .errunion_payload_ptr_set    => try airErrUnionPayloadPtrSet(f, inst),
             // zig fmt: on
         };
         switch (result_value) {
@@ -3164,6 +3165,7 @@ fn airWrapOptional(f: *Function, inst: Air.Inst.Index) !CValue {
     try writer.writeAll("};\n");
     return local;
 }
+
 fn airWrapErrUnionErr(f: *Function, inst: Air.Inst.Index) !CValue {
     if (f.liveness.isUnused(inst)) return CValue.none;
 
@@ -3183,6 +3185,11 @@ fn airWrapErrUnionErr(f: *Function, inst: Air.Inst.Index) !CValue {
     return local;
 }
 
+fn airErrUnionPayloadPtrSet(f: *Function, inst: Air.Inst.Index) !CValue {
+    _ = inst;
+    return f.fail("TODO: C backend: implement airErrUnionPayloadPtrSet", .{});
+}
+
 fn airWrapErrUnionPay(f: *Function, inst: Air.Inst.Index) !CValue {
     if (f.liveness.isUnused(inst))
         return CValue.none;
diff --git a/src/codegen/llvm.zig b/src/codegen/llvm.zig
index 8af74fce64..d8c19fba71 100644
--- a/src/codegen/llvm.zig
+++ b/src/codegen/llvm.zig
@@ -2238,6 +2238,7 @@ pub const FuncGen = struct {
                 .unwrap_errunion_payload_ptr => try self.airErrUnionPayload(inst, true),
                 .unwrap_errunion_err         => try self.airErrUnionErr(inst, false),
                 .unwrap_errunion_err_ptr     => try self.airErrUnionErr(inst, true),
+                .errunion_payload_ptr_set    => try self.airErrUnionPayloadPtrSet(inst),
 
                 .wrap_optional         => try self.airWrapOptional(inst),
                 .wrap_errunion_payload => try self.airWrapErrUnionPayload(inst),
@@ -3202,6 +3203,37 @@ pub const FuncGen = struct {
         return self.builder.buildExtractValue(operand, 0, "");
     }
 
+    fn airErrUnionPayloadPtrSet(self: *FuncGen, inst: Air.Inst.Index) !?*const llvm.Value {
+        const ty_op = self.air.instructions.items(.data)[inst].ty_op;
+        const operand = try self.resolveInst(ty_op.operand);
+        const error_set_ty = self.air.typeOf(ty_op.operand).childType();
+
+        const error_ty = error_set_ty.errorUnionSet();
+        const payload_ty = error_set_ty.errorUnionPayload();
+        const non_error_val = try self.dg.genTypedValue(.{ .ty = error_ty, .val = Value.zero });
+        if (!payload_ty.hasRuntimeBits()) {
+            // We have a pointer to a i1. We need to set it to 1 and then return the same pointer.
+            _ = self.builder.buildStore(non_error_val, operand);
+            return operand;
+        }
+        const index_type = self.context.intType(32);
+        {
+            // First set the non-error value.
+            const indices: [2]*const llvm.Value = .{
+                index_type.constNull(), // dereference the pointer
+                index_type.constNull(), // first field is the payload
+            };
+            const non_null_ptr = self.builder.buildInBoundsGEP(operand, &indices, indices.len, "");
+            _ = self.builder.buildStore(non_error_val, non_null_ptr);
+        }
+        // Then return the payload pointer.
+        const indices: [2]*const llvm.Value = .{
+            index_type.constNull(), // dereference the pointer
+            index_type.constInt(1, .False), // second field is the payload
+        };
+        return self.builder.buildInBoundsGEP(operand, &indices, indices.len, "");
+    }
+
     fn airWrapOptional(self: *FuncGen, inst: Air.Inst.Index) !?*const llvm.Value {
         if (self.liveness.isUnused(inst)) return null;
 
diff --git a/src/print_air.zig b/src/print_air.zig
index 5dc8219b12..289fcca669 100644
--- a/src/print_air.zig
+++ b/src/print_air.zig
@@ -189,6 +189,7 @@ const Writer = struct {
             .optional_payload,
             .optional_payload_ptr,
             .optional_payload_ptr_set,
+            .errunion_payload_ptr_set,
             .wrap_optional,
             .unwrap_errunion_payload,
             .unwrap_errunion_err,
diff --git a/test/behavior.zig b/test/behavior.zig
index 5b575ba190..68d0c40cd6 100644
--- a/test/behavior.zig
+++ b/test/behavior.zig
@@ -118,6 +118,7 @@ test {
                 _ = @import("behavior/sizeof_and_typeof.zig");
                 _ = @import("behavior/switch.zig");
                 _ = @import("behavior/widening.zig");
+                _ = @import("behavior/bugs/1442.zig");
 
                 if (builtin.zig_backend == .stage1) {
                     // Tests that only pass for the stage1 backend.
@@ -134,7 +135,6 @@ test {
                     _ = @import("behavior/bugs/920.zig");
                     _ = @import("behavior/bugs/1120.zig");
                     _ = @import("behavior/bugs/1421.zig");
-                    _ = @import("behavior/bugs/1442.zig");
                     _ = @import("behavior/bugs/1607.zig");
                     _ = @import("behavior/bugs/1851.zig");
                     _ = @import("behavior/bugs/2114.zig");
-- 
cgit v1.2.3