stage2: implement `@frameAddress`

2 files changed, 19 insertions, 0 deletions

diff --git a/src/codegen/c.zig b/src/codegen/c.zig
index f09acaa47c..331673cc55 100644
--- a/src/codegen/c.zig
+++ b/src/codegen/c.zig
@@ -1757,6 +1757,8 @@ 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) {
@@ -3198,6 +3200,11 @@ 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 e349f0186e..6f2cc9bbd0 100644
--- a/src/codegen/llvm.zig
+++ b/src/codegen/llvm.zig
@@ -2214,6 +2214,8 @@ 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),
@@ -3339,6 +3341,16 @@ 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;