LoongArch: Ensure sp 16-byte aligned for tlsdesc

Message ID 20240613110404.531591-2-xry111@xry111.site
State Committed
Commit 97aa7b7346bb9f1807e450c889fccbd2a7d8ff49
Headers
Series LoongArch: Ensure sp 16-byte aligned for tlsdesc |

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redhat-pt-bot/TryBot-apply_patch success Patch applied to master at the time it was sent
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Commit Message

Xi Ruoyao June 13, 2024, 11:04 a.m. UTC
  "ADDI sp, sp, 24" and "ADDI sp, sp, SZFCSREG" (SZFCSREG = 4) are
misaligning the stack: the ABI mandates a 16-byte alignment.  Fix it
by changing the first one to "ADDI sp, sp, 32", and reuse the spare 4th
slot for saving fcsr.

Reported-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
---

Tested on loongarch64-linux-gnu.

 sysdeps/loongarch/dl-tlsdesc.S | 10 ++++------
 sysdeps/loongarch/sys/asm.h    |  1 -
 2 files changed, 4 insertions(+), 7 deletions(-)
  

Patch

diff --git a/sysdeps/loongarch/dl-tlsdesc.S b/sysdeps/loongarch/dl-tlsdesc.S
index 15d5fa1c42..346b80f2ec 100644
--- a/sysdeps/loongarch/dl-tlsdesc.S
+++ b/sysdeps/loongarch/dl-tlsdesc.S
@@ -100,7 +100,7 @@  _dl_tlsdesc_undefweak:
 _dl_tlsdesc_dynamic:
 	/* Save just enough registers to support fast path, if we fall
 	   into slow path we will save additional registers.  */
-	ADDI	sp, sp, -24
+	ADDI	sp, sp, -32
 	REG_S	t0, sp, 0
 	REG_S	t1, sp, 8
 	REG_S	t2, sp, 16
@@ -141,7 +141,7 @@  Hign address	dynamic_block1 <----- dtv5  */
 	REG_L	t0, sp, 0
 	REG_L	t1, sp, 8
 	REG_L	t2, sp, 16
-	ADDI	sp, sp, 24
+	ADDI	sp, sp, 32
 	RET
 
 .Lslow:
@@ -171,9 +171,8 @@  Hign address	dynamic_block1 <----- dtv5  */
 	/* Save fcsr0 register.
 	   Only one physical fcsr0 register, fcsr1-fcsr3 are aliases
 	   of some fields in fcsr0.  */
-	ADDI	sp, sp, -SZFCSREG
 	movfcsr2gr  t0, fcsr0
-	st.w	t0, sp, 0
+	st.w	t0, sp, FRAME_SIZE + 24 /* Use the spare slot above t2 */
 
 	/* Whether support LASX.  */
 	la.global   t0, _rtld_global_ro
@@ -406,9 +405,8 @@  Hign address	dynamic_block1 <----- dtv5  */
 
 .Lfcsr:
 	/* Restore fcsr0 register.  */
-	ld.w	t0, sp, 0
+	ld.w	t0, sp, FRAME_SIZE + 24
 	movgr2fcsr  fcsr0, t0
-	ADDI	sp, sp, SZFCSREG
 
 #endif /* #ifndef __loongarch_soft_float */
 
diff --git a/sysdeps/loongarch/sys/asm.h b/sysdeps/loongarch/sys/asm.h
index 23c1d12914..51521a7eb4 100644
--- a/sysdeps/loongarch/sys/asm.h
+++ b/sysdeps/loongarch/sys/asm.h
@@ -25,7 +25,6 @@ 
 /* Macros to handle different pointer/register sizes for 32/64-bit code.  */
 #define SZREG 8
 #define SZFREG 8
-#define SZFCSREG 4
 #define SZVREG 16
 #define SZXREG 32
 #define REG_L ld.d