From 40590c8bf976a44451e161b4a75d7f8bac15a7d4 Mon Sep 17 00:00:00 2001
From: Koakuma <koachan@protonmail.com>
Date: Mon, 13 Jun 2022 22:34:10 +0700
Subject: [PATCH] stage2: sparc64: Save registers before calling another
 function

---
 src/arch/sparc64/CodeGen.zig | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/arch/sparc64/CodeGen.zig b/src/arch/sparc64/CodeGen.zig
index d0eee413ad..3c9083faa1 100644
--- a/src/arch/sparc64/CodeGen.zig
+++ b/src/arch/sparc64/CodeGen.zig
@@ -1081,6 +1081,13 @@ fn airCall(self: *Self, inst: Air.Inst.Index, modifier: std.builtin.CallOptions.
     // (SCD 2.4.1, page 3P-10)
     try self.spillConditionFlagsIfOccupied();
 
+    // Save caller-saved registers, but crucially *after* we save the
+    // compare flags as saving compare flags may require a new
+    // caller-saved register
+    for (abi.caller_preserved_regs) |reg| {
+        try self.register_manager.getReg(reg, null);
+    }
+
     for (info.args) |mc_arg, arg_i| {
         const arg = args[arg_i];
         const arg_ty = self.air.typeOf(arg);