[PATCH 4/4] tests/tcg/x86_64/fma: add test for exact-denormal output

Peter Maydell posted 4 patches 12 months ago
There is a newer version of this series
[PATCH 4/4] tests/tcg/x86_64/fma: add test for exact-denormal output
Posted by Peter Maydell 12 months ago
Add some fma test cases that check for correct handling of FTZ and
for the flag that indicates that the input denormal was consumed.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
 tests/tcg/x86_64/fma.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/tests/tcg/x86_64/fma.c b/tests/tcg/x86_64/fma.c
index 46f863005ed..34219614c0a 100644
--- a/tests/tcg/x86_64/fma.c
+++ b/tests/tcg/x86_64/fma.c
@@ -82,6 +82,18 @@ static testdata tests[] = {
      */
     { 0x3fdfffffffffffff, 0x001fffffffffffff, 0x801fffffffffffff, true,
       0x8010000000000000, 0x20 }, /* Enabling FTZ shouldn't change flags */
+    /*
+     * normal * 0 + a denormal. With FTZ disabled this gives an exact
+     * result (equal to the input denormal) that has consumed the denormal.
+     */
+    { 0x3cc8000000000000, 0x0000000000000000, 0x8008000000000000, false,
+      0x8008000000000000, 0x2 }, /* Denormal */
+    /*
+     * With FTZ enabled, this consumes the denormal, returns zero (because
+     * flushed) and indicates also Underflow and Precision.
+     */
+    { 0x3cc8000000000000, 0x0000000000000000, 0x8008000000000000, true,
+      0x8000000000000000, 0x32 }, /* Precision, Underflow, Denormal */
 };
 
 int main(void)
-- 
2.43.0