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Commit 6b9ce2b4 by Richard Earnshaw
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libgcc: arm: convert thumb1 code to unified syntax 

Unified syntax has been the official syntax for thumb1 assembly for
over 10 years now.  It's time we made preparations for that becoming
the default in the assembler.  But before we can start doing that we
really need to clean up some laggards from the olden days.  Libgcc
support for thumb1 is one such example.

This patch converts all of the legacy (disjoint) syntax that I could
find over to unified code.  The identification was done by using a
trick version of gas that defaulted to unified mode which then faults
if legacy syntax is encountered.  The code produced was then compared
against the old code to check for differences.  One such difference
does exist, but that is because in unified syntax 'movs rd, rn' is
encoded as 'lsls rd, rn, #0', rather than 'adds rd, rn, #0'; but that
is a deliberate change that was introduced because the lsls encoding
more closely reflects the behaviour of 'movs' in arm state (where only
some of the condition flags are modified).

	* config/arm/bpabi-v6m.S (aeabi_lcmp): Convert thumb1 code to unified
	syntax.
	(aeabi_ulcmp, aeabi_ldivmod, aeabi_uldivmod): Likewise.
	(aeabi_frsub, aeabi_cfcmpeq, aeabi_fcmpeq): Likewise.
	(aeabi_fcmp, aeabi_drsub, aeabi_cdrcmple): Likewise.
	(aeabi_cdcmpeq, aeabi_dcmpeq, aeabi_dcmp): Likewise.
	* config/arm/lib1funcs.S (Lend_fde): Convert thumb1 code to unified
	syntax.
	(divsi3, modsi3): Likewise.
	(clzdi2, ctzsi2): Likewise.
	* config/arm/libunwind.S (restore_core_regs): Convert thumb1 code to
	unified syntax.
	(UNWIND_WRAPPER): Likewise.
parent 8e6d0dba
Showing with 120 additions and 104 deletions
libgcc/ChangeLog
2020-03-03 Richard Earnshaw <rearnsha@arm.com>
* config/arm/bpabi-v6m.S (aeabi_lcmp): Convert thumb1 code to unified
syntax.
(aeabi_ulcmp, aeabi_ldivmod, aeabi_uldivmod): Likewise.
(aeabi_frsub, aeabi_cfcmpeq, aeabi_fcmpeq): Likewise.
(aeabi_fcmp, aeabi_drsub, aeabi_cdrcmple): Likewise.
(aeabi_cdcmpeq, aeabi_dcmpeq, aeabi_dcmp): Likewise.
* config/arm/lib1funcs.S (Lend_fde): Convert thumb1 code to unified
syntax.
(divsi3, modsi3): Likewise.
(clzdi2, ctzsi2): Likewise.
* config/arm/libunwind.S (restore_core_regs): Convert thumb1 code to
unified syntax.
(UNWIND_WRAPPER): Likewise.
2020-03-02 Martin Liska <mliska@suse.cz>
* libgcov-interface.c: Remove duplicate
......
libgcc/config/arm/bpabi-v6m.S
......@@ -39,21 +39,21 @@ FUNC_START aeabi_lcmp
cmp xxh, yyh
beq 1f
bgt 2f
mov r0, #1
neg r0, r0
movs r0, #1
negs r0, r0
RET
2:
mov r0, #1
movs r0, #1
RET
1:
sub r0, xxl, yyl
subs r0, xxl, yyl
beq 1f
bhi 2f
mov r0, #1
neg r0, r0
movs r0, #1
negs r0, r0
RET
2:
mov r0, #1
movs r0, #1
1:
RET
FUNC_END aeabi_lcmp
......@@ -65,15 +65,15 @@ FUNC_START aeabi_lcmp
FUNC_START aeabi_ulcmp
cmp xxh, yyh
bne 1f
sub r0, xxl, yyl
subs r0, xxl, yyl
beq 2f
1:
bcs 1f
mov r0, #1
neg r0, r0
movs r0, #1
negs r0, r0
RET
1:
mov r0, #1
movs r0, #1
2:
RET
FUNC_END aeabi_ulcmp
......@@ -91,29 +91,29 @@ FUNC_START aeabi_ulcmp
cmp xxl, #0
2:
beq 3f
mov xxh, #0
mvn xxh, xxh @ 0xffffffff
mov xxl, xxh
movs xxh, #0
mvns xxh, xxh @ 0xffffffff
movs xxl, xxh
3:
.else
blt 6f
bgt 4f
cmp xxl, #0
beq 5f
4: mov xxl, #0
mvn xxl, xxl @ 0xffffffff
lsr xxh, xxl, #1 @ 0x7fffffff
4: movs xxl, #0
mvns xxl, xxl @ 0xffffffff
lsrs xxh, xxl, #1 @ 0x7fffffff
b 5f
6: mov xxh, #0x80
lsl xxh, xxh, #24 @ 0x80000000
mov xxl, #0
6: movs xxh, #0x80
lsls xxh, xxh, #24 @ 0x80000000
movs xxl, #0
5:
.endif
@ tailcalls are tricky on v6-m.
push {r0, r1, r2}
ldr r0, 1f
adr r1, 1f
add r0, r1
adds r0, r1
str r0, [sp, #8]
@ We know we are not on armv4t, so pop pc is safe.
pop {r0, r1, pc}
......@@ -128,15 +128,15 @@ FUNC_START aeabi_ulcmp
FUNC_START aeabi_ldivmod
test_div_by_zero signed
push {r0, r1}
mov r0, sp
push {r0, lr}
ldr r0, [sp, #8]
bl SYM(__gnu_ldivmod_helper)
ldr r3, [sp, #4]
mov lr, r3
add sp, sp, #8
pop {r2, r3}
push {r0, r1}
mov r0, sp
push {r0, lr}
ldr r0, [sp, #8]
bl SYM(__gnu_ldivmod_helper)
ldr r3, [sp, #4]
mov lr, r3
add sp, sp, #8
pop {r2, r3}
RET
FUNC_END aeabi_ldivmod
......@@ -147,15 +147,15 @@ FUNC_START aeabi_ldivmod
FUNC_START aeabi_uldivmod
test_div_by_zero unsigned
push {r0, r1}
mov r0, sp
push {r0, lr}
ldr r0, [sp, #8]
bl SYM(__udivmoddi4)
ldr r3, [sp, #4]
mov lr, r3
add sp, sp, #8
pop {r2, r3}
push {r0, r1}
mov r0, sp
push {r0, lr}
ldr r0, [sp, #8]
bl SYM(__udivmoddi4)
ldr r3, [sp, #4]
mov lr, r3
add sp, sp, #8
pop {r2, r3}
RET
FUNC_END aeabi_uldivmod
......@@ -166,9 +166,9 @@ FUNC_START aeabi_uldivmod
FUNC_START aeabi_frsub
push {r4, lr}
mov r4, #1
lsl r4, #31
eor r0, r0, r4
movs r4, #1
lsls r4, #31
eors r0, r0, r4
bl __aeabi_fadd
pop {r4, pc}
......@@ -181,7 +181,7 @@ FUNC_START aeabi_frsub
FUNC_START aeabi_cfrcmple
mov ip, r0
mov r0, r1
movs r0, r1
mov r1, ip
b 6f
......@@ -196,8 +196,8 @@ FUNC_ALIAS aeabi_cfcmple aeabi_cfcmpeq
cmp r0, #0
@ Clear the C flag if the return value was -1, indicating
@ that the first operand was smaller than the second.
bmi 1f
mov r1, #0
bmi 1f
movs r1, #0
cmn r0, r1
1:
pop {r0, r1, r2, r3, r4, pc}
......@@ -210,8 +210,8 @@ FUNC_START aeabi_fcmpeq
push {r4, lr}
bl __eqsf2
neg r0, r0
add r0, r0, #1
negs r0, r0
adds r0, r0, #1
pop {r4, pc}
FUNC_END aeabi_fcmpeq
......@@ -223,10 +223,10 @@ FUNC_START aeabi_fcmp\cond
bl __\helper\mode
cmp r0, #0
b\cond 1f
mov r0, #0
movs r0, #0
pop {r4, pc}
1:
mov r0, #1
movs r0, #1
pop {r4, pc}
FUNC_END aeabi_fcmp\cond
......@@ -244,9 +244,9 @@ COMPARISON ge, ge
FUNC_START aeabi_drsub
push {r4, lr}
mov r4, #1
lsl r4, #31
eor xxh, xxh, r4
movs r4, #1
lsls r4, #31
eors xxh, xxh, r4
bl __aeabi_dadd
pop {r4, pc}
......@@ -259,10 +259,10 @@ FUNC_START aeabi_drsub
FUNC_START aeabi_cdrcmple
mov ip, r0
mov r0, r2
movs r0, r2
mov r2, ip
mov ip, r1
mov r1, r3
movs r1, r3
mov r3, ip
b 6f
......@@ -277,8 +277,8 @@ FUNC_ALIAS aeabi_cdcmple aeabi_cdcmpeq
cmp r0, #0
@ Clear the C flag if the return value was -1, indicating
@ that the first operand was smaller than the second.
bmi 1f
mov r1, #0
bmi 1f
movs r1, #0
cmn r0, r1
1:
pop {r0, r1, r2, r3, r4, pc}
......@@ -291,8 +291,8 @@ FUNC_START aeabi_dcmpeq
push {r4, lr}
bl __eqdf2
neg r0, r0
add r0, r0, #1
negs r0, r0
adds r0, r0, #1
pop {r4, pc}
FUNC_END aeabi_dcmpeq
......@@ -304,10 +304,10 @@ FUNC_START aeabi_dcmp\cond
bl __\helper\mode
cmp r0, #0
b\cond 1f
mov r0, #0
movs r0, #0
pop {r4, pc}
1:
mov r0, #1
movs r0, #1
pop {r4, pc}
FUNC_END aeabi_dcmp\cond
......
libgcc/config/arm/libunwind.S
......@@ -63,28 +63,28 @@
/* r0 points to a 16-word block. Upload these values to the actual core
state. */
FUNC_START restore_core_regs
mov r1, r0
add r1, r1, #52
ldmia r1!, {r3, r4, r5}
sub r3, r3, #4
mov ip, r3
str r5, [r3]
mov lr, r4
movs r1, r0
adds r1, r1, #52
ldmia r1!, {r3, r4, r5}
subs r3, r3, #4
mov ip, r3
str r5, [r3]
mov lr, r4
/* Restore r8-r11. */
mov r1, r0
add r1, r1, #32
ldmia r1!, {r2, r3, r4, r5}
mov r8, r2
mov r9, r3
mov sl, r4
mov fp, r5
mov r1, r0
add r1, r1, #8
ldmia r1!, {r2, r3, r4, r5, r6, r7}
ldr r1, [r0, #4]
ldr r0, [r0]
mov sp, ip
pop {pc}
movs r1, r0
adds r1, r1, #32
ldmia r1!, {r2, r3, r4, r5}
mov r8, r2
mov r9, r3
mov sl, r4
mov fp, r5
movs r1, r0
adds r1, r1, #8
ldmia r1!, {r2, r3, r4, r5, r6, r7}
ldr r1, [r0, #4]
ldr r0, [r0]
mov sp, ip
pop {pc}
FUNC_END restore_core_regs
UNPREFIX restore_core_regs
......@@ -132,38 +132,38 @@ FUNC_START gnu_Unwind_Save_WMMXC
FUNC_START \name
/* Create a phase2_vrs structure. */
/* Save r0 in the PC slot so we can use it as a scratch register. */
push {r0}
add r0, sp, #4
push {r0, lr} /* Push original SP and LR. */
push {r0}
add r0, sp, #4
push {r0, lr} /* Push original SP and LR. */
/* Make space for r8-r12. */
sub sp, sp, #20
sub sp, sp, #20
/* Save low registers. */
push {r0, r1, r2, r3, r4, r5, r6, r7}
push {r0, r1, r2, r3, r4, r5, r6, r7}
/* Save high registers. */
add r0, sp, #32
mov r1, r8
mov r2, r9
mov r3, sl
mov r4, fp
mov r5, ip
stmia r0!, {r1, r2, r3, r4, r5}
add r0, sp, #32
mov r1, r8
mov r2, r9
mov r3, sl
mov r4, fp
mov r5, ip
stmia r0!, {r1, r2, r3, r4, r5}
/* Restore original low register values. */
add r0, sp, #4
ldmia r0!, {r1, r2, r3, r4, r5}
add r0, sp, #4
ldmia r0!, {r1, r2, r3, r4, r5}
/* Restore orginial r0. */
ldr r0, [sp, #60]
str r0, [sp]
ldr r0, [sp, #60]
str r0, [sp]
/* Demand-save flags, plus an extra word for alignment. */
mov r3, #0
push {r2, r3}
movs r3, #0
push {r2, r3}
/* Point r1 at the block. Pass r[0..nargs) unchanged. */
add r\nargs, sp, #4
add r\nargs, sp, #4
bl SYM (__gnu\name)
bl SYM (__gnu\name)
ldr r3, [sp, #64]
add sp, sp, #72
bx r3
ldr r3, [sp, #64]
add sp, sp, #72
bx r3
FUNC_END \name
UNPREFIX \name
......
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