From 9fee8b75aa3d8a85395dd0e94fb4a5754817ae24 Mon Sep 17 00:00:00 2001 From: Gabe Black Date: Mon, 17 Aug 2009 18:36:18 -0700 Subject: [PATCH] X86: Implement a media floating point subtract microop. --- src/arch/x86/isa/microops/mediaop.isa | 46 +++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/src/arch/x86/isa/microops/mediaop.isa b/src/arch/x86/isa/microops/mediaop.isa index 334944222..b9cfc0075 100644 --- a/src/arch/x86/isa/microops/mediaop.isa +++ b/src/arch/x86/isa/microops/mediaop.isa @@ -620,4 +620,50 @@ let {{ } FpDestReg.uqw = result; ''' + + class Msubf(MediaOp): + code = ''' + union floatInt + { + float f; + uint32_t i; + }; + union doubleInt + { + double d; + uint64_t i; + }; + + assert(srcSize == destSize); + int size = srcSize; + int sizeBits = size * 8; + assert(srcSize == 4 || srcSize == 8); + int items = (ext & 0x1) ? 1: (sizeof(FloatRegBits) / size); + uint64_t result = FpDestReg.uqw; + + for (int i = 0; i < items; i++) { + int hiIndex = (i + 1) * sizeBits - 1; + int loIndex = (i + 0) * sizeBits; + uint64_t arg1Bits = bits(FpSrcReg1.uqw, hiIndex, loIndex); + uint64_t arg2Bits = bits(FpSrcReg2.uqw, hiIndex, loIndex); + uint64_t resBits; + + if (size == 4) { + floatInt arg1, arg2, res; + arg1.i = arg1Bits; + arg2.i = arg2Bits; + res.f = arg1.f - arg2.f; + resBits = res.i; + } else { + doubleInt arg1, arg2, res; + arg1.i = arg1Bits; + arg2.i = arg2Bits; + res.d = arg1.d - arg2.d; + resBits = res.i; + } + + result = insertBits(result, hiIndex, loIndex, resBits); + } + FpDestReg.uqw = result; + ''' }}; -- 2.30.2