github.com/mtsmfm/go/src@v0.0.0-20221020090648-44bdcb9f8fde/reflect/float32reg_riscv64.s (about)

     1  // Copyright 2022 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  #include "textflag.h"
     6  
     7  // riscv64 allows 32-bit floats to live in the bottom
     8  // part of the register, it expects them to be NaN-boxed.
     9  // These functions are needed to ensure correct conversions
    10  // on riscv64.
    11  
    12  // Convert float32->uint64
    13  TEXT ·archFloat32ToReg(SB),NOSPLIT,$0-16
    14  	MOVF	val+0(FP), F1
    15  	MOVD	F1, ret+8(FP)
    16  	RET
    17  
    18  // Convert uint64->float32
    19  TEXT ·archFloat32FromReg(SB),NOSPLIT,$0-12
    20  	// Normally a float64->float32 conversion
    21  	// would need rounding, but riscv64 store valid
    22  	// float32 in the lower 32 bits, thus we only need to
    23  	// unboxed the NaN-box by store a float32.
    24  	MOVD	reg+0(FP), F1
    25  	MOVF	F1, ret+8(FP)
    26  	RET
    27