stage2: fix frame_address AIR instruction

Various places were assuming different union tags. Now it is
consistently a no-op instruction, just like the similar
instruction ret_addr.

2 files changed, 30 insertions, 26 deletions

diff --git a/src/codegen/c.zig b/src/codegen/c.zig
index 331673cc55..3e47637c76 100644
--- a/src/codegen/c.zig
+++ b/src/codegen/c.zig
@@ -1588,7 +1588,8 @@ fn genBody(f: *Function, body: []const Air.Inst.Index) error{ AnalysisFail, OutO
             .arg      => airArg(f),
 
             .breakpoint => try airBreakpoint(f),
-            .ret_addr   => try airRetAddr(f),
+            .ret_addr   => try airRetAddr(f, inst),
+            .frame_addr => try airFrameAddress(f, inst),
             .unreach    => try airUnreach(f),
             .fence      => try airFence(f, inst),
 
@@ -1757,8 +1758,6 @@ fn genBody(f: *Function, body: []const Air.Inst.Index) error{ AnalysisFail, OutO
             .wrap_errunion_payload       => try airWrapErrUnionPay(f, inst),
             .wrap_errunion_err           => try airWrapErrUnionErr(f, inst),
             .errunion_payload_ptr_set    => try airErrUnionPayloadPtrSet(f, inst),
-
-            .frame_address => try airFrameAddress(f, inst),
             // zig fmt: on
         };
         switch (result_value) {
@@ -2719,12 +2718,20 @@ fn airBreakpoint(f: *Function) !CValue {
     return CValue.none;
 }
 
-fn airRetAddr(f: *Function) !CValue {
+fn airRetAddr(f: *Function, inst: Air.Inst.Index) !CValue {
+    if (f.liveness.isUnused(inst)) return CValue.none;
     const local = try f.allocLocal(Type.usize, .Const);
     try f.object.writer().writeAll(" = zig_return_address();\n");
     return local;
 }
 
+fn airFrameAddress(f: *Function, inst: Air.Inst.Index) !CValue {
+    if (f.liveness.isUnused(inst)) return CValue.none;
+    const local = try f.allocLocal(Type.usize, .Const);
+    try f.object.writer().writeAll(" = zig_frame_address();\n");
+    return local;
+}
+
 fn airFence(f: *Function, inst: Air.Inst.Index) !CValue {
     const atomic_order = f.air.instructions.items(.data)[inst].fence;
     const writer = f.object.writer();
@@ -3200,11 +3207,6 @@ fn airErrUnionPayloadPtrSet(f: *Function, inst: Air.Inst.Index) !CValue {
     return f.fail("TODO: C backend: implement airErrUnionPayloadPtrSet", .{});
 }
 
-fn airFrameAddress(f: *Function, inst: Air.Inst.Index) !CValue {
-    _ = inst;
-    return f.fail("TODO: C backend: implement airFrameAddress", .{});
-}
-
 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 6f2cc9bbd0..ddd6e7c06b 100644
--- a/src/codegen/llvm.zig
+++ b/src/codegen/llvm.zig
@@ -2135,6 +2135,7 @@ pub const FuncGen = struct {
                 .switch_br      => try self.airSwitchBr(inst),
                 .breakpoint     => try self.airBreakpoint(inst),
                 .ret_addr       => try self.airRetAddr(inst),
+                .frame_addr     => try self.airFrameAddress(inst),
                 .call           => try self.airCall(inst),
                 .cond_br        => try self.airCondBr(inst),
                 .intcast        => try self.airIntCast(inst),
@@ -2214,8 +2215,6 @@ pub const FuncGen = struct {
                 .wrap_errunion_payload => try self.airWrapErrUnionPayload(inst),
                 .wrap_errunion_err     => try self.airWrapErrUnionErr(inst),
 
-                .frame_address => try self.airFrameAddress(inst),
-
                 .constant => unreachable,
                 .const_ty => unreachable,
                 .unreach  => self.airUnreach(inst),
@@ -3341,16 +3340,6 @@ pub const FuncGen = struct {
         return partial;
     }
 
-    fn airFrameAddress(self: *FuncGen, inst: Air.Inst.Index) !?*const llvm.Value {
-        if (self.liveness.isUnused(inst)) return null;
-
-        const llvm_i32 = try self.dg.llvmType(Type.initTag(.i32));
-        const llvm_fn = self.getIntrinsic("llvm.frameaddress", &.{llvm_i32});
-        const ptr_val = self.builder.buildCall(llvm_fn, &[_]*const llvm.Value{llvm_i32.constNull()}, 1, .Fast, .Auto, "");
-        const llvm_usize = try self.dg.llvmType(Type.usize);
-        return self.builder.buildPtrToInt(ptr_val, llvm_usize, "");
-    }
-
     fn airMin(self: *FuncGen, inst: Air.Inst.Index) !?*const llvm.Value {
         if (self.liveness.isUnused(inst)) return null;
 
@@ -4112,12 +4101,25 @@ pub const FuncGen = struct {
     }
 
     fn airRetAddr(self: *FuncGen, inst: Air.Inst.Index) !?*const llvm.Value {
-        _ = inst;
-        const i32_zero = self.context.intType(32).constNull();
-        const usize_llvm_ty = try self.dg.llvmType(Type.usize);
+        if (self.liveness.isUnused(inst)) return null;
+
+        const llvm_i32 = self.context.intType(32);
         const llvm_fn = self.getIntrinsic("llvm.returnaddress", &.{});
-        const ptr_val = self.builder.buildCall(llvm_fn, &[_]*const llvm.Value{i32_zero}, 1, .Fast, .Auto, "");
-        return self.builder.buildPtrToInt(ptr_val, usize_llvm_ty, "");
+        const params = [_]*const llvm.Value{llvm_i32.constNull()};
+        const ptr_val = self.builder.buildCall(llvm_fn, &params, params.len, .Fast, .Auto, "");
+        const llvm_usize = try self.dg.llvmType(Type.usize);
+        return self.builder.buildPtrToInt(ptr_val, llvm_usize, "");
+    }
+
+    fn airFrameAddress(self: *FuncGen, inst: Air.Inst.Index) !?*const llvm.Value {
+        if (self.liveness.isUnused(inst)) return null;
+
+        const llvm_i32 = self.context.intType(32);
+        const llvm_fn = self.getIntrinsic("llvm.frameaddress", &.{llvm_i32});
+        const params = [_]*const llvm.Value{llvm_i32.constNull()};
+        const ptr_val = self.builder.buildCall(llvm_fn, &params, params.len, .Fast, .Auto, "");
+        const llvm_usize = try self.dg.llvmType(Type.usize);
+        return self.builder.buildPtrToInt(ptr_val, llvm_usize, "");
     }
 
     fn airFence(self: *FuncGen, inst: Air.Inst.Index) !?*const llvm.Value {