From: Ruinland ChuanTzu Tsai <ruinland@andestech.com>
Date: Mon, 2 Dec 2019 11:06:52 +0000 (+0800)
Subject: riscv64: fix fesetenv(FE_DFL_ENV) crash
X-Git-Tag: v1.2.0~57
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=c0b4a7b25430e4495bb213a5c3ad43e26c6bff20;p=oweals%2Fmusl.git

riscv64: fix fesetenv(FE_DFL_ENV) crash

When FE_DFL_ENV is passed to fesetenv(), the very first instruction
lw t1, 0(a0) will fail since a0 is -1.
---

diff --git a/src/fenv/riscv64/fenv.S b/src/fenv/riscv64/fenv.S
index f149003d..0ea78bf9 100644
--- a/src/fenv/riscv64/fenv.S
+++ b/src/fenv/riscv64/fenv.S
@@ -45,8 +45,11 @@ fegetenv:
 .global fesetenv
 .type fesetenv, %function
 fesetenv:
+	li t2, -1
+	li t1, 0
+	beq a0, t2, 1f
 	lw t1, 0(a0)
-	fscsr t0, t1
+1:	fscsr t1
 	li a0, 0
 	ret