From: Ali Saidi <Ali.Saidi@ARM.com>
Date: Fri, 15 Feb 2013 22:40:08 +0000 (-0500)
Subject: arm: fix some fp comparisons that worked by accident.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=db5c478e707ba5c7ffe8713ece5534924208500a;p=gem5.git

arm: fix some fp comparisons that worked by accident.

The explict tests in the follwing fp comparison operations were
incorrect as they checked for only signaling NaNs and not quite-NaNs
as well. When compiled with gcc, the comparison generates a fp exception
that causes the FE_INVALID flag to be set and we check for it, so even
though the check was incorrect, the correct exception was set. With clang
this behavior seems to not occur. The checks are updated to test for nans and
the behavior is now correct with both clang and gcc.
---

diff --git a/src/arch/arm/isa/insts/neon.isa b/src/arch/arm/isa/insts/neon.isa
index b1ad1eeb3..3296b3b55 100644
--- a/src/arch/arm/isa/insts/neon.isa
+++ b/src/arch/arm/isa/insts/neon.isa
@@ -565,7 +565,7 @@ output exec {{
     static float
     vcgtFunc(float op1, float op2)
     {
-        if (isSnan(op1) || isSnan(op2))
+        if (std::isnan(op1) || std::isnan(op2))
             return 2.0;
         return (op1 > op2) ? 0.0 : 1.0;
     }
@@ -573,7 +573,7 @@ output exec {{
     static float
     vcgeFunc(float op1, float op2)
     {
-        if (isSnan(op1) || isSnan(op2))
+        if (std::isnan(op1) || std::isnan(op2))
             return 2.0;
         return (op1 >= op2) ? 0.0 : 1.0;
     }
@@ -589,7 +589,7 @@ output exec {{
     static float
     vcleFunc(float op1, float op2)
     {
-        if (isSnan(op1) || isSnan(op2))
+        if (std::isnan(op1) || std::isnan(op2))
             return 2.0;
         return (op1 <= op2) ? 0.0 : 1.0;
     }
@@ -597,7 +597,7 @@ output exec {{
     static float
     vcltFunc(float op1, float op2)
     {
-        if (isSnan(op1) || isSnan(op2))
+        if (std::isnan(op1) || std::isnan(op2))
             return 2.0;
         return (op1 < op2) ? 0.0 : 1.0;
     }
@@ -605,7 +605,7 @@ output exec {{
     static float
     vacgtFunc(float op1, float op2)
     {
-        if (isSnan(op1) || isSnan(op2))
+        if (std::isnan(op1) || std::isnan(op2))
             return 2.0;
         return (fabsf(op1) > fabsf(op2)) ? 0.0 : 1.0;
     }
@@ -613,7 +613,7 @@ output exec {{
     static float
     vacgeFunc(float op1, float op2)
     {
-        if (isSnan(op1) || isSnan(op2))
+        if (std::isnan(op1) || std::isnan(op2))
             return 2.0;
         return (fabsf(op1) >= fabsf(op2)) ? 0.0 : 1.0;
     }