From 9ccc706bdd00062b778b9d312166974f61a4c9db Mon Sep 17 00:00:00 2001 From: Corinna Vinschen Date: Mon, 16 Dec 2019 10:50:17 +0100 Subject: [PATCH] Cygwin: ilogbl: Make sure to return FP_ILGB0 on zero input Signed-off-by: Corinna Vinschen --- winsup/cygwin/math/ilogbl.S | 10 ++++++++++ winsup/cygwin/release/3.1.0 | 3 +++ 2 files changed, 13 insertions(+) diff --git a/winsup/cygwin/math/ilogbl.S b/winsup/cygwin/math/ilogbl.S index f68082ce6..a4fe503ad 100644 --- a/winsup/cygwin/math/ilogbl.S +++ b/winsup/cygwin/math/ilogbl.S @@ -23,6 +23,8 @@ __MINGW_USYMBOL(ilogbl): andb %ah, %dh cmpb $0x05, %dh je 1f /* Is +-Inf, jump. */ + cmpb $0x40, %dh + je 2f /* Is +-Inf, jump. */ fxtract pushq %rax @@ -37,6 +39,9 @@ __MINGW_USYMBOL(ilogbl): 1: fstp %st movl $0x7fffffff, %eax ret +2: fstp %st + movl $0x80000001, %eax /* FP_ILOGB0 */ + ret #else fldt 4(%esp) /* I added the following ugly construct because ilogb(+-Inf) is @@ -48,6 +53,8 @@ __MINGW_USYMBOL(ilogbl): andb %ah, %dh cmpb $0x05, %dh je 1f /* Is +-Inf, jump. */ + cmpb $0x40, %dh + je 2f /* Is +-Inf, jump. */ fxtract pushl %eax @@ -62,4 +69,7 @@ __MINGW_USYMBOL(ilogbl): 1: fstp %st movl $0x7fffffff, %eax ret +2: fstp %st + movl $0x80000001, %eax /* FP_ILOGB0 */ + ret #endif diff --git a/winsup/cygwin/release/3.1.0 b/winsup/cygwin/release/3.1.0 index b0e845657..681ea5db9 100644 --- a/winsup/cygwin/release/3.1.0 +++ b/winsup/cygwin/release/3.1.0 @@ -108,3 +108,6 @@ Bug Fixes - Fix an assertion failure when /cygdrive contains an offline network drive. Addresses: https://cygwin.com/ml/cygwin/2019-12/msg00016.html + +- Fix return value of ilogbl for 0 input. + Addresses: https://cygwin.com/ml/cygwin/2019-12/msg00074.html