From a8e8c4f433fb3cce354950ba72136b84abb78015 Mon Sep 17 00:00:00 2001 From: Andreas Sandberg Date: Tue, 18 Jun 2013 16:30:06 +0200 Subject: x86: Fix loading of floating point constants This changeset actually fixes two issues: * The lfpimm instruction didn't work correctly when applied to a floating point constant (it did work for integers containing the bit string representation of a constant) since it used reinterpret_cast to convert a double to a uint64_t. This caused a compilation error, at least, in gcc 4.6.3. * The instructions loading floating point constants in the x87 processor didn't work correctly since they just stored a truncated integer instead of a double in the floating point register. This changeset fixes the old microcode by using lfpimm instruction instead of the limm instructions. --- src/arch/x86/isa/insts/x87/load_constants/load_0_1_or_pi.py | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'src/arch/x86/isa/insts/x87/load_constants/load_0_1_or_pi.py') diff --git a/src/arch/x86/isa/insts/x87/load_constants/load_0_1_or_pi.py b/src/arch/x86/isa/insts/x87/load_constants/load_0_1_or_pi.py index cb8947312..9f22af89b 100644 --- a/src/arch/x86/isa/insts/x87/load_constants/load_0_1_or_pi.py +++ b/src/arch/x86/isa/insts/x87/load_constants/load_0_1_or_pi.py @@ -40,17 +40,17 @@ microcode = ''' def macroop FLDZ { - limm ufp1, "double(0)" + lfpimm ufp1, 0.0 movfp st(-1), ufp1, spm=-1 }; def macroop FLD1 { - limm ufp1, "double(1)" + lfpimm ufp1, 1.0 movfp st(-1), ufp1, spm=-1 }; def macroop FLDPI { - limm ufp1, "double(3.14159265359)" + lfpimm ufp1, 3.14159265359 movfp st(-1), ufp1, spm=-1 }; -- cgit v1.2.3