Merge release-5-0 into master

[alexxy/gromacs.git] / src / gromacs / simd / tests / simd_math.cpp

diff --git a/src/gromacs/simd/tests/simd_math.cpp b/src/gromacs/simd/tests/simd_math.cpp
index b4959ceba7377e8397d245ea8210e4acb115438b..a3213c99a5397be9fefabeedb793ede8a4f807c9 100644 (file)
--- a/src/gromacs/simd/tests/simd_math.cpp
+++ b/src/gromacs/simd/tests/simd_math.cpp
@@ -279,6 +279,23 @@ TEST_F(SimdMathTest, gmxSimdExp2R)
 {
     setRange(-100, 100);
     GMX_EXPECT_SIMD_FUNC_NEAR(ref_exp2, gmx_simd_exp2_r);
+
+    // We do not care about the SIMD implementation getting denormal values right,
+    // but they must be clamped to zero rather than producing garbage.
+    // Check by setting the absolute tolerance to machine precision.
+    setAbsTol(GMX_REAL_EPS);
+
+    // First two values will have denormal results in single, third value in double too.
+    GMX_EXPECT_SIMD_REAL_NEAR(setSimdRealFrom3R(ref_exp2(-150.0), ref_exp2(-300.0), ref_exp2(-1050.0)),
+                              gmx_simd_exp2_r(setSimdRealFrom3R(-150.0, -300.0, -1050.0)));
+
+    // Reset absolute tolerance to enforce ULP checking
+    setAbsTol(0.0);
+
+    // Make sure that underflowing values are set to zero.
+    // First two values underflow in single, third value in double too.
+    GMX_EXPECT_SIMD_REAL_NEAR(setSimdRealFrom3R(ref_exp2(-200.0), ref_exp2(-600.0), ref_exp2(-1500.0)),
+                              gmx_simd_exp2_r(setSimdRealFrom3R(-200.0, -600.0, -1500.0)));
 }
 #endif
 
@@ -292,6 +309,22 @@ TEST_F(SimdMathTest, gmxSimdExpR)
 {
     setRange(-75, 75);
     GMX_EXPECT_SIMD_FUNC_NEAR(ref_exp, gmx_simd_exp_r);
+
+    // We do not care about the SIMD implementation getting denormal values right,
+    // but they must be clamped to zero rather than producing garbage.
+    // Check by setting the absolute tolerance to machine precision.
+    setAbsTol(GMX_REAL_EPS);
+    // First two values will have denormal results in single, third value in double too.
+    GMX_EXPECT_SIMD_REAL_NEAR(setSimdRealFrom3R(ref_exp(-90.0), ref_exp(-100.0), ref_exp(-725.0)),
+                              gmx_simd_exp_r(setSimdRealFrom3R(-90.0, -100.0, -725.0)));
+
+    // Reset absolute tolerance to enforce ULP checking
+    setAbsTol(0.0);
+
+    // Make sure that underflowing values are set to zero.
+    // First two values underflow in single, third value in double too.
+    GMX_EXPECT_SIMD_REAL_NEAR(setSimdRealFrom3R(ref_exp(-150.0), ref_exp(-300.0), ref_exp(-800.0)),
+                              gmx_simd_exp_r(setSimdRealFrom3R(-150.0, -300.0, -800.0)));
 }
 
 /*! \brief Function wrapper for erf(x), with argument/return in default Gromacs precision.