From cca7c50b54bbf5d763da839582edff69bd9d051d Mon Sep 17 00:00:00 2001
From: xtex <xtex@astrafall.org>
Date: Sun, 30 Aug 2026 21:15:42 +0800
Subject: [PATCH] loongarch: ABI resolve for f16/f32/f64/f128

---
 src/codegen/loongarch/Select.zig | 26 +++++++++++++++++++++-----
 1 file changed, 21 insertions(+), 5 deletions(-)

diff --git a/src/codegen/loongarch/Select.zig b/src/codegen/loongarch/Select.zig
index 04197dc7c4f41d43a2f5ed408823eeda83b2ee33..1b1dd5a4b858d781c19461ffae00da265c6e77a0 100644
--- a/src/codegen/loongarch/Select.zig
+++ b/src/codegen/loongarch/Select.zig
@@ -3758,7 +3758,7 @@ pub fn body(isel: *Select, air_body: []const Air.Inst.Index) error{ OutOfMemory,
                 } else if (dst_tag == .float and src_tag == .float) {
                     assert(dst_ty.floatBits(isel.target) == src_ty.floatBits(isel.target));
                     try dst_vi.value.defMove(isel, ty_op.operand);
-                } else if (dst_ty.isAbiInt(zcu) and src_tag == .float and isel.canUseFprForFloat(src_ty)) {
+                } else if (dst_ty.isAbiInt(zcu) and src_tag == .float and isel.canUseFprForFloat(src_ty.floatBits(isel.target))) {
                     const dst_int_info = dst_ty.intInfo(zcu);
                     assert(dst_int_info.bits == src_ty.floatBits(isel.target));
 
@@ -3773,7 +3773,7 @@ pub fn body(isel: *Select, air_body: []const Air.Inst.Index) error{ OutOfMemory,
                         64 => .@"movfr2gr.d"(dst_reg, src_reg),
                     });
                     try src_mat.finish(isel);
-                } else if (dst_tag == .float and src_ty.isAbiInt(zcu) and isel.canUseFprForFloat(dst_ty)) {
+                } else if (dst_tag == .float and src_ty.isAbiInt(zcu) and isel.canUseFprForFloat(dst_ty.floatBits(isel.target))) {
                     const src_int_info = src_ty.intInfo(zcu);
                     assert(dst_ty.floatBits(isel.target) == src_int_info.bits);
 
@@ -6942,6 +6942,7 @@ pub const CallAbiIterator = struct {
             },
             .simple_type => |simple_type| switch (simple_type) {
                 .f80 => continue :type_key .{ .int_type = .{ .signedness = .unsigned, .bits = 80 } },
+                .f128 => continue :type_key .{ .int_type = .{ .signedness = .unsigned, .bits = 128 } },
                 .usize,
                 .isize,
                 .c_char,
@@ -6959,7 +6960,22 @@ pub const CallAbiIterator = struct {
                     .signedness = .unsigned,
                     .bits = zcu.errorSetBits(),
                 } },
-                .f16, .f32, .f64, .f128, .c_longdouble => return isel.fail("CallAbiIterator.resolve({t})", .{simple_type}),
+                .f16, .f32, .f64 => {
+                    const bits = ty.floatBits(isel.target);
+                    if (isel.canUseFprForFloat(bits)) {
+                        if (it.allocReg(.fpr)) |reg| {
+                            wip_vi.setHintRegister(isel, reg);
+                            if (bits != 16) {
+                                wip_vi.setHintModifier(isel, .fromFloatBits(bits));
+                            } else {
+                                wip_vi.setHintModifier(isel, .floating32);
+                            }
+                        } else it.assignStack(wip_vi);
+                    } else {
+                        continue :type_key .{ .int_type = .{ .signedness = .unsigned, .bits = bits } };
+                    }
+                },
+                .c_longdouble => return isel.fail("CallAbiIterator.resolve({t})", .{simple_type}),
                 else => return isel.fail("CallAbiIterator.resolve({t})", .{simple_type}),
             },
             .struct_type => {
@@ -7280,8 +7296,8 @@ fn vectorBits(isel: *Select) u7 {
     }
 }
 
-fn canUseFprForFloat(isel: *Select, ty: ZigType) bool {
-    return ty.floatBits(isel.target) <= isel.fprBits();
+fn canUseFprForFloat(isel: *Select, bits: u16) bool {
+    return bits <= isel.fprBits();
 }
 
 fn typeOfField(isel: *Select, ty: ZigType, offset: u64) ?ZigType {
-- 
2.54.0