[gcc r10-10451] [RS6000] Adjust gcc asm for power10

[gcc r10-10451] [RS6000] Adjust gcc asm for power10

[Alan Modra]

https://gcc.gnu.org/g:445922b932d938a9f47a32b97fefbd07aa4a2841

commit r10-10451-g445922b932d938a9f47a32b97fefbd07aa4a2841
Author: Alan Modra <amodra@gmail.com>
Date:   Mon Sep 28 16:42:33 2020 +0930

    [RS6000] Adjust gcc asm for power10
    
    Generate assembly with .localentry,1 functions using @notoc calls.
    This patch makes libgcc.a asm look the same as power10 pcrel as far as
    toc/notoc is concerned.
    
    Otherwise calling between functions that advertise as using the TOC
    and those that don't, will require linker call stubs in statically
    linked code.
    
    gcc/
            * config/rs6000/ppc-asm.h: Support __PCREL__ code.
    libgcc/
            * config/rs6000/morestack.S,
            * config/rs6000/tramp.S: Support __PCREL__ code.
    libitm/
            * config/powerpc/sjlj.S: Support __PCREL__ code.
    
    (cherry picked from commit 2dd7b93778d551b6981c8086ecb38e26f677bd2b)

Diff:
---
 gcc/config/rs6000/ppc-asm.h      |  9 +++++++++
 libgcc/config/rs6000/morestack.S | 30 +++++++++++++++++++++---------
 libgcc/config/rs6000/tramp.S     |  6 ++++++
 libitm/config/powerpc/sjlj.S     | 18 +++++++++++++++++-
 4 files changed, 53 insertions(+), 10 deletions(-)

diff --git a/gcc/config/rs6000/ppc-asm.h b/gcc/config/rs6000/ppc-asm.h
index 48edc9945d7..e0bce9c5aec 100644
--- a/gcc/config/rs6000/ppc-asm.h
+++ b/gcc/config/rs6000/ppc-asm.h
@@ -262,6 +262,14 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #undef toc
 
 #define FUNC_NAME(name) GLUE(__USER_LABEL_PREFIX__,name)
+#ifdef __PCREL__
+#define JUMP_TARGET(name) GLUE(FUNC_NAME(name),@notoc)
+#define FUNC_START(name) \
+	.type FUNC_NAME(name),@function; \
+	.globl FUNC_NAME(name); \
+FUNC_NAME(name): \
+	.localentry FUNC_NAME(name),1
+#else
 #define JUMP_TARGET(name) FUNC_NAME(name)
 #define FUNC_START(name) \
 	.type FUNC_NAME(name),@function; \
@@ -270,6 +278,7 @@ FUNC_NAME(name): \
 0:	addis 2,12,(.TOC.-0b)@ha; \
 	addi 2,2,(.TOC.-0b)@l; \
 	.localentry FUNC_NAME(name),.-FUNC_NAME(name)
+#endif /* !__PCREL__ */
 
 #define HIDDEN_FUNC(name) \
   FUNC_START(name) \
diff --git a/libgcc/config/rs6000/morestack.S b/libgcc/config/rs6000/morestack.S
index 1b8ebb5dc3b..ac33c882c30 100644
--- a/libgcc/config/rs6000/morestack.S
+++ b/libgcc/config/rs6000/morestack.S
@@ -55,11 +55,18 @@
 	.type name,@function;				\
 name##:
 
+#ifdef __PCREL__
+#define ENTRY(name)					\
+	ENTRY0(name);					\
+	.localentry name, 1
+#define JUMP_TARGET(name) name##@notoc
+#else
 #define ENTRY(name)					\
 	ENTRY0(name);					\
 0:	addis %r2,%r12,.TOC.-0b@ha;			\
         addi %r2,%r2,.TOC.-0b@l;			\
 	.localentry name, .-name
+#endif
 
 #else
 
@@ -81,6 +88,9 @@ BODY_LABEL(name)##:
 
 #define SIZE(name) .size name, .-BODY_LABEL(name)
 
+#ifndef JUMP_TARGET
+#define JUMP_TARGET(name) name
+#endif
 
 	.text
 # Just like __morestack, but with larger excess allocation
@@ -156,7 +166,7 @@ ENTRY0(__morestack)
 	stdu %r1,-MORESTACK_FRAMESIZE(%r1)
 
 	# void __morestack_block_signals (void)
-	bl __morestack_block_signals
+	bl JUMP_TARGET(__morestack_block_signals)
 
 	# void *__generic_morestack (size_t *pframe_size,
 	#			     void *old_stack,
@@ -164,7 +174,7 @@ ENTRY0(__morestack)
 	addi %r3,%r29,NEWSTACKSIZE_SAVE
 	mr %r4,%r29
 	li %r5,0			# no copying from old stack
-	bl __generic_morestack
+	bl JUMP_TARGET(__generic_morestack)
 
 # Start using new stack
 	stdu %r29,-32(%r3)		# back-chain
@@ -183,7 +193,7 @@ ENTRY0(__morestack)
 	std %r3,-0x7000-64(%r13)	# tcbhead_t.__private_ss
 
 	# void __morestack_unblock_signals (void)
-	bl __morestack_unblock_signals
+	bl JUMP_TARGET(__morestack_unblock_signals)
 
 # Set up for a call to the target function, located 3
 # instructions after __morestack's return address.
@@ -218,11 +228,11 @@ ENTRY0(__morestack)
 	std %r10,PARAMREG_SAVE+56(%r29)
 #endif
 
-	bl __morestack_block_signals
+	bl JUMP_TARGET(__morestack_block_signals)
 
 	# void *__generic_releasestack (size_t *pavailable)
 	addi %r3,%r29,NEWSTACKSIZE_SAVE
-	bl __generic_releasestack
+	bl JUMP_TARGET(__generic_releasestack)
 
 # Reset __private_ss stack guard to value for old stack
 	ld %r12,NEWSTACKSIZE_SAVE(%r29)
@@ -231,7 +241,7 @@ ENTRY0(__morestack)
 .LEHE0:
 	std %r3,-0x7000-64(%r13)	# tcbhead_t.__private_ss
 
-	bl __morestack_unblock_signals
+	bl JUMP_TARGET(__morestack_unblock_signals)
 
 # Use old stack again.
 	mr %r1,%r29
@@ -260,13 +270,15 @@ cleanup:
 	std %r3,PARAMREG_SAVE(%r29)	# Save exception header
 	# size_t __generic_findstack (void *stack)
 	mr %r3,%r29
-	bl __generic_findstack
+	bl JUMP_TARGET(__generic_findstack)
 	sub %r3,%r29,%r3
 	addi %r3,%r3,BACKOFF
 	std %r3,-0x7000-64(%r13)	# tcbhead_t.__private_ss
 	ld %r3,PARAMREG_SAVE(%r29)
-	bl _Unwind_Resume
+	bl JUMP_TARGET(_Unwind_Resume)
+#ifndef __PCREL__
 	nop
+#endif
 	.cfi_endproc
 	SIZE (__morestack)
 
@@ -310,7 +322,7 @@ ENTRY(__stack_split_initialize)
 	# void __generic_morestack_set_initial_sp (void *sp, size_t len)
 	mr %r3,%r1
 	li %r4, 0x4000
-	b __generic_morestack_set_initial_sp
+	b JUMP_TARGET(__generic_morestack_set_initial_sp)
 # The lack of .cfi_endproc here is deliberate.  This function and the
 # following ones can all use the default FDE.
 	SIZE (__stack_split_initialize)
diff --git a/libgcc/config/rs6000/tramp.S b/libgcc/config/rs6000/tramp.S
index 47f97e93e6a..1fc5f37f88f 100644
--- a/libgcc/config/rs6000/tramp.S
+++ b/libgcc/config/rs6000/tramp.S
@@ -139,15 +139,21 @@ trampoline_size = .-trampoline_initial
 /* R5 = function address */
 /* R6 = static chain */
 
+#ifndef __PCREL__
 	.pushsection ".toc","aw"
 .LC0:
 	.quad	trampoline_initial-8
 	.popsection
+#endif
 
 FUNC_START(__trampoline_setup)
 	.cfi_startproc
+#ifdef __PCREL__
+	pla 7,(trampoline_initial-8)@pcrel
+#else
 	addis 7,2,.LC0@toc@ha
 	ld 7,.LC0@toc@l(7)	/* trampoline address -8 */
+#endif
 
 	cmpwi	cr1,r4,trampoline_size	/* verify that the trampoline is big enough */
 	srwi	r4,r4,3		/* # doublewords to move */
diff --git a/libitm/config/powerpc/sjlj.S b/libitm/config/powerpc/sjlj.S
index a963fc350bb..bcb0e73a285 100644
--- a/libitm/config/powerpc/sjlj.S
+++ b/libitm/config/powerpc/sjlj.S
@@ -26,7 +26,23 @@
 
 #include "asmcfi.h"
 
-#if defined(__powerpc64__) && _CALL_ELF == 2
+#if defined(__powerpc64__) && _CALL_ELF == 2 && defined(__PCREL__)
+.macro FUNC name
+	.globl	\name
+	.type	\name, @function
+\name:
+	.localentry \name, 1
+.endm
+.macro END name
+	.size	\name, . - \name
+.endm
+.macro HIDDEN name
+	.hidden	\name
+.endm
+.macro CALL name
+	bl	\name @notoc
+.endm
+#elif defined(__powerpc64__) && _CALL_ELF == 2
 .macro FUNC name
         .globl  \name
         .type   \name, @function