ARM Architecture Reference Manual ARMv7-A and ARMv7-R edition

Application Level Programmers’ Model
The FPCompareEQ(), FPCompareGE() and FPCompareGT() functions are used to describe Advanced SIMD
instructions that perform floating-point comparisons.
// FPCompareEQ()
// =============
boolean FPCompareEQ(bits(32) op1, bits(32) op2, boolean fpscr_controlled)
fpscr_val = if fpscr_controlled then FPSCR else StandardFPSCRValue();
(type1,sign1,value1) = FPUnpack(op1, fpscr_val);
(type2,sign2,value2) = FPUnpack(op2, fpscr_val);
if type1==FPType_SNaN || type1==FPType_QNaN || type2==FPType_SNaN || type2==FPType_QNaN then
result = FALSE;
if type1==FPType_SNaN || type2==FPType_SNaN then
FPProcessException(FPExc_InvalidOp, fpscr_val);
else
// All non-NaN cases can be evaluated on the values produced by FPUnpack()
result = (value1 == value2);
return result;
// FPCompareGE()
// =============
boolean FPCompareGE(bits(32) op1, bits(32) op2, boolean fpscr_controlled)
fpscr_val = if fpscr_controlled then FPSCR else StandardFPSCRValue();
(type1,sign1,value1) = FPUnpack(op1, fpscr_val);
(type2,sign2,value2) = FPUnpack(op2, fpscr_val);
if type1==FPType_SNaN || type1==FPType_QNaN || type2==FPType_SNaN || type2==FPType_QNaN then
result = FALSE;
FPProcessException(FPExc_InvalidOp, fpscr_val);
else
// All non-NaN cases can be evaluated on the values produced by FPUnpack()
result = (value1 >= value2);
return result;
// FPCompareGT()
// =============
boolean FPCompareGT(bits(32) op1, bits(32) op2, boolean fpscr_controlled)
fpscr_val = if fpscr_controlled then FPSCR else StandardFPSCRValue();
(type1,sign1,value1) = FPUnpack(op1, fpscr_val);
(type2,sign2,value2) = FPUnpack(op2, fpscr_val);
if type1==FPType_SNaN || type1==FPType_QNaN || type2==FPType_SNaN || type2==FPType_QNaN then
result = FALSE;
FPProcessException(FPExc_InvalidOp, fpscr_val);
else
// All non-NaN cases can be evaluated on the values produced by FPUnpack()
result = (value1 > value2);
return result;
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