From 501a6b55853af549fae72723e74271f2a4ec7cf6 Mon Sep 17 00:00:00 2001
From: Brett Warren <brett.warren@arm.com>
Date: Fri, 27 Nov 2020 15:28:42 +0000
Subject: [PATCH] arm/sysv: reverted clang VFP mitigation

Since commit e3d2812ce43940aacae5bab2d0e965278cb1e7ea,
seperate instructions were used when compiling under clang,
as clang didn't allow the directives at the time. This mitigation
now causes compilation to fail under clang 10, as described by
https://github.com/libffi/libffi/issues/607. Now that
clang supports the LDC and SDC instructions, this mitigation
has been reverted.

Upstream-Status: Submitted [https://github.com/libffi/libffi/pull/747]
Signed-off-by: Brett Warren <brett.warren@arm.com>
---
 src/arm/sysv.S | 33 ---------------------------------
 1 file changed, 33 deletions(-)

diff --git a/src/arm/sysv.S b/src/arm/sysv.S
index fb36213..e4272a1 100644
--- a/src/arm/sysv.S
+++ b/src/arm/sysv.S
@@ -142,13 +142,8 @@ ARM_FUNC_START(ffi_call_VFP)
 
 	cmp	r3, #3			@ load only d0 if possible
 	ite	le
-#ifdef __clang__
-	vldrle d0, [r0]
-	vldmgt r0, {d0-d7}
-#else
 	ldcle	p11, cr0, [r0]		@ vldrle d0, [r0]
 	ldcgt	p11, cr0, [r0], {16}	@ vldmgt r0, {d0-d7}
-#endif
 	add	r0, r0, #64		@ discard the vfp register args
 	/* FALLTHRU */
 ARM_FUNC_END(ffi_call_VFP)
@@ -193,25 +188,13 @@ ARM_FUNC_START(ffi_call_SYSV)
 #endif
 0:
 E(ARM_TYPE_VFP_S)
-#ifdef __clang__
-	vstr s0, [r2]
-#else
 	stc	p10, cr0, [r2]		@ vstr s0, [r2]
-#endif
 	pop	{fp,pc}
 E(ARM_TYPE_VFP_D)
-#ifdef __clang__
-	vstr d0, [r2]
-#else
 	stc	p11, cr0, [r2]		@ vstr d0, [r2]
-#endif
 	pop	{fp,pc}
 E(ARM_TYPE_VFP_N)
-#ifdef __clang__
-	vstm r2, {d0-d3}
-#else
 	stc	p11, cr0, [r2], {8}	@ vstm r2, {d0-d3}
-#endif
 	pop	{fp,pc}
 E(ARM_TYPE_INT64)
 	str	r1, [r2, #4]
@@ -320,11 +303,7 @@ ARM_FUNC_START(ffi_closure_VFP)
 	add	ip, sp, #16
 	sub	sp, sp, #64+32			@ allocate frame
 	cfi_adjust_cfa_offset(64+32)
-#ifdef __clang__
-	vstm sp, {d0-d7}
-#else
 	stc	p11, cr0, [sp], {16}		@ vstm sp, {d0-d7}
-#endif
 	stmdb	sp!, {ip,lr}
 
 	/* See above.  */
@@ -358,25 +337,13 @@ ARM_FUNC_START_LOCAL(ffi_closure_ret)
 	cfi_rel_offset(lr, 4)
 0:
 E(ARM_TYPE_VFP_S)
-#ifdef __clang__
-	vldr s0, [r2]
-#else
 	ldc	p10, cr0, [r2]			@ vldr s0, [r2]
-#endif
 	b	call_epilogue
 E(ARM_TYPE_VFP_D)
-#ifdef __clang__
-	vldr d0, [r2]
-#else
 	ldc	p11, cr0, [r2]			@ vldr d0, [r2]
-#endif
 	b	call_epilogue
 E(ARM_TYPE_VFP_N)
-#ifdef __clang__
-	vldm r2, {d0-d3}
-#else
 	ldc	p11, cr0, [r2], {8}		@ vldm r2, {d0-d3}
-#endif
 	b	call_epilogue
 E(ARM_TYPE_INT64)
 	ldr	r1, [r2, #4]
-- 
2.25.1