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_logarithm.py | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'src/arch/x86/isa/insts/x87/load_constants/load_logarithm.py') diff --git a/src/arch/x86/isa/insts/x87/load_constants/load_logarithm.py b/src/arch/x86/isa/insts/x87/load_constants/load_logarithm.py index 7e71c4006..88eb01086 100644 --- a/src/arch/x86/isa/insts/x87/load_constants/load_logarithm.py +++ b/src/arch/x86/isa/insts/x87/load_constants/load_logarithm.py @@ -40,22 +40,22 @@ microcode = ''' def macroop FLDL2E { - limm ufp1, "double(1.44269504089)" + lfpimm ufp1, 1.44269504089 movfp st(-1), ufp1, spm=-1 }; def macroop FLDL2T { - limm ufp1, "double(3.32192809489)" + lfpimm ufp1, 3.32192809489 movfp st(-1), ufp1, spm=-1 }; def macroop FLDLG2 { - limm ufp1, "double(0.30102999566)" + lfpimm ufp1, 0.30102999566 movfp st(-1), ufp1, spm=-1 }; def macroop FLDLN2 { - limm ufp1, "double(0.69314718056)" + lfpimm ufp1, 0.69314718056 movfp st(-1), ufp1, spm=-1 }; -- cgit v1.2.3