Commit e68cc2e5cd for qemu.org

commit e68cc2e5cd28333ac76d757ed2db7d2f7635d09a
Author: wangyang <wangyang25@otcaix.iscas.ac.cn>
Date:   Thu Aug 13 18:39:06 2026 +0800

    target/riscv: enforce even register constraints for Zdinx fcvt pairs

    fcvt.d.h and fcvt.h.d access a 64-bit double held in a register
    pair, so under Zdinx/Zhinxmin the odd-rd (fcvt.d.h) and odd-rs1
    (fcvt.h.d) encodings are reserved.  Add the missing REQUIRE_EVEN
    checks so those encodings raise an illegal-instruction exception
    instead of retiring.

    Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/4109
    Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
    Signed-off-by: wangyang <wangyang25@otcaix.iscas.ac.cn>
    Message-ID: <ea287909fd6043e0bbcdbfdcb0cc8063@wangyang25.otcaix.iscas.ac.cn>
    Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

diff --git a/target/riscv/tcg/insn_trans/trans_rvzfh.c.inc b/target/riscv/tcg/insn_trans/trans_rvzfh.c.inc
index 88711fb076..b17ef9541c 100644
--- a/target/riscv/tcg/insn_trans/trans_rvzfh.c.inc
+++ b/target/riscv/tcg/insn_trans/trans_rvzfh.c.inc
@@ -419,6 +419,7 @@ static bool trans_fcvt_d_h(DisasContext *ctx, arg_fcvt_d_h *a)
     REQUIRE_FPU;
     REQUIRE_ZFHMIN_OR_ZHINXMIN(ctx);
     REQUIRE_ZDINX_OR_D(ctx);
+    REQUIRE_EVEN(ctx, a->rd);

     TCGv_i64 dest = dest_fpr(ctx, a->rd);
     TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
@@ -453,6 +454,7 @@ static bool trans_fcvt_h_d(DisasContext *ctx, arg_fcvt_h_d *a)
     REQUIRE_FPU;
     REQUIRE_ZFHMIN_OR_ZHINXMIN(ctx);
     REQUIRE_ZDINX_OR_D(ctx);
+    REQUIRE_EVEN(ctx, a->rs1);

     TCGv_i64 dest = dest_fpr(ctx, a->rd);
     TCGv_i64 src1 = get_fpr_d(ctx, a->rs1);