[Libclc-dev] [PATCH 3/3] powr: Use denormal path only

Jan Vesely via Libclc-dev libclc-dev at lists.llvm.org
Thu Apr 12 11:53:53 PDT 2018


It's OK to either flush to 0 or return denormal result if the device
does not support denormals. See sec 7.2 and 7.5.3 of OCL specs
Fixes CTS on carrizo and turks.
Signed-off-by: Jan Vesely <jan.vesely at rutgers.edu>
---
 generic/lib/math/clc_powr.cl | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/generic/lib/math/clc_powr.cl b/generic/lib/math/clc_powr.cl
index 9074a8b..ef97d3c 100644
--- a/generic/lib/math/clc_powr.cl
+++ b/generic/lib/math/clc_powr.cl
@@ -165,17 +165,7 @@ _CLC_DEF _CLC_OVERLOAD float __clc_powr(float x, float y)
     tv = USE_TABLE(exp_tbl_ep, j);
 
     float expylogx = mad(tv.s0, poly, mad(tv.s1, poly, tv.s1)) + tv.s0;
-    float sexpylogx;
-    if (!__clc_fp32_subnormals_supported()) {
-		int explg = ((as_uint(expylogx) & EXPBITS_SP32 >> 23) - 127);
-		m = (23-(m + 149)) == 0 ? 1: m;
-		uint mantissa =  ((as_uint(expylogx) & MANTBITS_SP32)|IMPBIT_SP32) >> (23-(m + 149));
-		sexpylogx = as_float(mantissa);
-    } else {
-		sexpylogx = expylogx * as_float(0x1 << (m + 149));
-    }
-
-
+    float sexpylogx = expylogx * as_float(0x1 << (m + 149));
     float texpylogx = as_float(as_int(expylogx) + m2);
     expylogx = m < -125 ? sexpylogx : texpylogx;
 
-- 
2.14.3



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