On 6/29/24 01:56, Akihiko Odaki wrote:
clang version 18.1.6 does not allow specifying an integer as the value
of a single-precision register. Manually bit-cast into float with vmov
first.

Signed-off-by: Akihiko Odaki <akihiko.od...@daynix.com>
---
  tests/tcg/arm/fcvt.c | 4 +++-
  1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tests/tcg/arm/fcvt.c b/tests/tcg/arm/fcvt.c
index f631197287a1..5263f607b59c 100644
--- a/tests/tcg/arm/fcvt.c
+++ b/tests/tcg/arm/fcvt.c
@@ -355,7 +355,9 @@ static void convert_half_to_single(void)
print_half_number(i, input);
  #if defined(__arm__)
-        asm("vcvtb.f32.f16 %0, %1" : "=w" (output) : "x" ((uint32_t)input));
+        float tmp;
+        asm("vmov %0, %1" : "=w" (tmp) : "r" (input));
+        asm("vcvtb.f32.f16 %0, %1" : "=w" (output) : "x" (tmp));
  #else
          asm("fcvt %s0, %h1" : "=w" (output) : "w" (input));
  #endif

Better as

 #if defined(__arm__)
-        asm("vcvtb.f32.f16 %0, %1" : "=w" (output) : "x" ((uint32_t)input));
+        /*
+         * Clang refuses to allocate an integer to a fp register.
+         * Perform the move from a general register by hand.
+         */
+        asm("vmov %0, %1\n\t"
+            "vcvtb.f32.f16 %0, %0" : "=w" (output) : "r" (input));
 #else

without the C temporary.  With that,

Reviewed-by: Richard Henderson <richard.hender...@linaro.org>


r~

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