Add a "fork" of musl as //fusl.

fusl/src/fenv/mips/fenv.s

Index: fusl/src/fenv/mips/fenv.s
diff --git a/fusl/src/fenv/mips/fenv.s b/fusl/src/fenv/mips/fenv.s
new file mode 100644
index 0000000000000000000000000000000000000000..62828212ab965fba35e6cd205d001b5103245a26
--- /dev/null
+++ b/fusl/src/fenv/mips/fenv.s
@@ -0,0 +1,67 @@
+.set noreorder
+
+.global feclearexcept
+.type  feclearexcept,@function
+feclearexcept:
+	and     $4, $4, 0x7c
+	cfc1    $5, $31
+	or      $5, $5, $4
+	xor     $5, $5, $4
+	ctc1    $5, $31
+	jr      $ra
+	li      $2, 0
+
+.global feraiseexcept
+.type  feraiseexcept,@function
+feraiseexcept:
+	and     $4, $4, 0x7c
+	cfc1    $5, $31
+	or      $5, $5, $4
+	ctc1    $5, $31
+	jr      $ra
+	li      $2, 0
+
+.global fetestexcept
+.type  fetestexcept,@function
+fetestexcept:
+	and     $4, $4, 0x7c
+	cfc1    $2, $31
+	jr      $ra
+	and     $2, $2, $4
+
+.global fegetround
+.type  fegetround,@function
+fegetround:
+	cfc1    $2, $31
+	jr      $ra
+	andi    $2, $2, 3
+
+.global __fesetround
+.type __fesetround,@function
+__fesetround:
+	cfc1    $5, $31
+	li      $6, -4
+	and     $5, $5, $6
+	or      $5, $5, $4
+	ctc1    $5, $31
+	jr      $ra
+	li      $2, 0
+
+.global fegetenv
+.type  fegetenv,@function
+fegetenv:
+	cfc1    $5, $31
+	sw      $5, 0($4)
+	jr      $ra
+	li      $2, 0
+
+.global fesetenv
+.type  fesetenv,@function
+fesetenv:
+	addiu   $5, $4, 1
+	beq     $5, $0, 1f
+	 nop
+	lw      $5, 0($4)
+1:	ctc1    $5, $31
+	jr      $ra
+	li      $2, 0