[tip:core/rseq] rseq/selftests/x86: Work around bogus gcc-8 optimisation

From: tip-bot for Mathieu Desnoyers
Date: Fri Apr 19 2019 - 14:47:00 EST

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Commit-ID: 3c0f67279fb57568b436dece3aa20651aa6c5a05
Gitweb: https://git.kernel.org/tip/3c0f67279fb57568b436dece3aa20651aa6c5a05
Author: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
AuthorDate: Fri, 19 Apr 2019 10:53:27 -0400
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Fri, 19 Apr 2019 20:35:10 +0200

rseq/selftests/x86: Work around bogus gcc-8 optimisation

At least the following versions of gcc-8:

- gcc version 8.0.1 20180414 (experimental) [trunk revision 259383] (Ubuntu 8-20180414-1ubuntu2)
- gcc 8.2.0-7ubuntu1 (Ubuntu 18.10 (Cosmic)),

generate broken assembler with asm goto that have a thread-local storage
"m" input operand on both x86-32 and x86-64. For instance:

__thread int var;

static int fct(void)
{
asm goto ( "jmp %l[testlabel]\n\t"
: : [var] "m" (var) : : testlabel);
return 0;
testlabel:
return 1;
}

int main()
{
return fct();
}

% gcc-8 -O2 -o test-asm-goto test-asm-goto.c
/tmp/ccAdHJbe.o: In function `main':
test-asm-goto.c:(.text.startup+0x1): undefined reference to `.L2'
collect2: error: ld returned 1 exit status

% gcc-8 -m32 -O2 -o test-asm-goto test-asm-goto.c
/tmp/ccREsVXA.o: In function `main':
test-asm-goto.c:(.text.startup+0x1): undefined reference to `.L2'
collect2: error: ld returned 1 exit status

Work-around this compiler bug in the rseq-x86.h header by passing the
address of the __rseq_abi TLS as a register operand rather than using
the "m" input operand.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Ben Maurer <bmaurer@xxxxxx>
Cc: Boqun Feng <boqun.feng@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Chris Lameter <cl@xxxxxxxxx>
Cc: Dave Watson <davejwatson@xxxxxx>
Cc: H . Peter Anvin <hpa@xxxxxxxxx>
Cc: Joel Fernandes <joelaf@xxxxxxxxxx>
Cc: Josh Triplett <josh@xxxxxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Michael Kerrisk <mtk.manpages@xxxxxxxxx>
Cc: Paul E . McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Cc: Paul Turner <pjt@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: linux-api@xxxxxxxxxxxxxxx
Cc: linux-kselftest@xxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20190419145327.12736-1-mathieu.desnoyers@xxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
tools/testing/selftests/rseq/rseq-x86.h | 144 ++++++++++++++++----------------
1 file changed, 70 insertions(+), 74 deletions(-)

diff --git a/tools/testing/selftests/rseq/rseq-x86.h b/tools/testing/selftests/rseq/rseq-x86.h
index 089410a314e9..a5341044a2f5 100644
--- a/tools/testing/selftests/rseq/rseq-x86.h
+++ b/tools/testing/selftests/rseq/rseq-x86.h
@@ -9,6 +9,16 @@

#define RSEQ_SIG 0x53053053

+/*
+ * Due to a compiler optimization bug in gcc-8 with asm goto and TLS asm input
+ * operands, we cannot use "m" input operands, and rather pass the __rseq_abi
+ * address through a "r" input operand.
+ */
+
+/* Offset of cpu_id and rseq_cs fields in struct rseq. */
+#define RSEQ_CPU_ID_OFFSET 4
+#define RSEQ_CS_OFFSET 8
+
#ifdef __x86_64__

#define rseq_smp_mb() \
@@ -51,12 +61,12 @@ do { \
#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \
RSEQ_INJECT_ASM(1) \
"leaq " __rseq_str(cs_label) "(%%rip), %%rax\n\t" \
- "movq %%rax, %[" __rseq_str(rseq_cs) "]\n\t" \
+ "movq %%rax, " __rseq_str(rseq_cs) "\n\t" \
__rseq_str(label) ":\n\t"

#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \
RSEQ_INJECT_ASM(2) \
- "cmpl %[" __rseq_str(cpu_id) "], %[" __rseq_str(current_cpu_id) "]\n\t" \
+ "cmpl %[" __rseq_str(cpu_id) "], " __rseq_str(current_cpu_id) "\n\t" \
"jnz " __rseq_str(label) "\n\t"

#define RSEQ_ASM_DEFINE_ABORT(label, teardown, abort_label) \
@@ -84,14 +94,14 @@ int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
"cmpq %[v], %[expect]\n\t"
"jnz %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
"cmpq %[v], %[expect]\n\t"
"jnz %l[error2]\n\t"
#endif
@@ -102,8 +112,7 @@ int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)
RSEQ_ASM_DEFINE_ABORT(4, "", abort)
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
[v] "m" (*v),
[expect] "r" (expect),
[newv] "r" (newv)
@@ -141,15 +150,15 @@ int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
"movq %[v], %%rbx\n\t"
"cmpq %%rbx, %[expectnot]\n\t"
"je %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
"movq %[v], %%rbx\n\t"
"cmpq %%rbx, %[expectnot]\n\t"
"je %l[error2]\n\t"
@@ -164,8 +173,7 @@ int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,
RSEQ_ASM_DEFINE_ABORT(4, "", abort)
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
/* final store input */
[v] "m" (*v),
[expectnot] "r" (expectnot),
@@ -200,11 +208,11 @@ int rseq_addv(intptr_t *v, intptr_t count, int cpu)
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
#endif
/* final store */
"addq %[count], %[v]\n\t"
@@ -213,8 +221,7 @@ int rseq_addv(intptr_t *v, intptr_t count, int cpu)
RSEQ_ASM_DEFINE_ABORT(4, "", abort)
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
/* final store input */
[v] "m" (*v),
[count] "er" (count)
@@ -245,14 +252,14 @@ int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
"cmpq %[v], %[expect]\n\t"
"jnz %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
"cmpq %[v], %[expect]\n\t"
"jnz %l[error2]\n\t"
#endif
@@ -266,8 +273,7 @@ int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,
RSEQ_ASM_DEFINE_ABORT(4, "", abort)
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
/* try store input */
[v2] "m" (*v2),
[newv2] "r" (newv2),
@@ -315,8 +321,8 @@ int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
"cmpq %[v], %[expect]\n\t"
"jnz %l[cmpfail]\n\t"
@@ -325,7 +331,7 @@ int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
"jnz %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(5)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
"cmpq %[v], %[expect]\n\t"
"jnz %l[error2]\n\t"
"cmpq %[v2], %[expect2]\n\t"
@@ -338,8 +344,7 @@ int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
RSEQ_ASM_DEFINE_ABORT(4, "", abort)
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
/* cmp2 input */
[v2] "m" (*v2),
[expect2] "r" (expect2),
@@ -385,14 +390,14 @@ int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,
"movq %[dst], %[rseq_scratch1]\n\t"
"movq %[len], %[rseq_scratch2]\n\t"
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
"cmpq %[v], %[expect]\n\t"
"jnz 5f\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 6f)
"cmpq %[v], %[expect]\n\t"
"jnz 7f\n\t"
#endif
@@ -440,8 +445,7 @@ int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,
#endif
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
/* final store input */
[v] "m" (*v),
[expect] "r" (expect),
@@ -533,12 +537,12 @@ do { \

#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \
RSEQ_INJECT_ASM(1) \
- "movl $" __rseq_str(cs_label) ", %[rseq_cs]\n\t" \
+ "movl $" __rseq_str(cs_label) ", " __rseq_str(rseq_cs) "\n\t" \
__rseq_str(label) ":\n\t"

#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \
RSEQ_INJECT_ASM(2) \
- "cmpl %[" __rseq_str(cpu_id) "], %[" __rseq_str(current_cpu_id) "]\n\t" \
+ "cmpl %[" __rseq_str(cpu_id) "], " __rseq_str(current_cpu_id) "\n\t" \
"jnz " __rseq_str(label) "\n\t"

#define RSEQ_ASM_DEFINE_ABORT(label, teardown, abort_label) \
@@ -566,14 +570,14 @@ int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
"cmpl %[v], %[expect]\n\t"
"jnz %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
"cmpl %[v], %[expect]\n\t"
"jnz %l[error2]\n\t"
#endif
@@ -584,8 +588,7 @@ int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)
RSEQ_ASM_DEFINE_ABORT(4, "", abort)
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
[v] "m" (*v),
[expect] "r" (expect),
[newv] "r" (newv)
@@ -623,15 +626,15 @@ int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
"movl %[v], %%ebx\n\t"
"cmpl %%ebx, %[expectnot]\n\t"
"je %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
"movl %[v], %%ebx\n\t"
"cmpl %%ebx, %[expectnot]\n\t"
"je %l[error2]\n\t"
@@ -646,8 +649,7 @@ int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,
RSEQ_ASM_DEFINE_ABORT(4, "", abort)
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
/* final store input */
[v] "m" (*v),
[expectnot] "r" (expectnot),
@@ -682,11 +684,11 @@ int rseq_addv(intptr_t *v, intptr_t count, int cpu)
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
#endif
/* final store */
"addl %[count], %[v]\n\t"
@@ -695,8 +697,7 @@ int rseq_addv(intptr_t *v, intptr_t count, int cpu)
RSEQ_ASM_DEFINE_ABORT(4, "", abort)
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
/* final store input */
[v] "m" (*v),
[count] "ir" (count)
@@ -727,14 +728,14 @@ int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
"cmpl %[v], %[expect]\n\t"
"jnz %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
"cmpl %[v], %[expect]\n\t"
"jnz %l[error2]\n\t"
#endif
@@ -749,8 +750,7 @@ int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,
RSEQ_ASM_DEFINE_ABORT(4, "", abort)
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
/* try store input */
[v2] "m" (*v2),
[newv2] "m" (newv2),
@@ -789,15 +789,15 @@ int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect,
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
"movl %[expect], %%eax\n\t"
"cmpl %[v], %%eax\n\t"
"jnz %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
"movl %[expect], %%eax\n\t"
"cmpl %[v], %%eax\n\t"
"jnz %l[error2]\n\t"
@@ -813,8 +813,7 @@ int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect,
RSEQ_ASM_DEFINE_ABORT(4, "", abort)
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
/* try store input */
[v2] "m" (*v2),
[newv2] "r" (newv2),
@@ -854,8 +853,8 @@ int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
"cmpl %[v], %[expect]\n\t"
"jnz %l[cmpfail]\n\t"
@@ -864,7 +863,7 @@ int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
"jnz %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(5)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), %l[error1])
"cmpl %[v], %[expect]\n\t"
"jnz %l[error2]\n\t"
"cmpl %[expect2], %[v2]\n\t"
@@ -878,8 +877,7 @@ int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
RSEQ_ASM_DEFINE_ABORT(4, "", abort)
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
/* cmp2 input */
[v2] "m" (*v2),
[expect2] "r" (expect2),
@@ -926,15 +924,15 @@ int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,
"movl %[dst], %[rseq_scratch1]\n\t"
"movl %[len], %[rseq_scratch2]\n\t"
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
"movl %[expect], %%eax\n\t"
"cmpl %%eax, %[v]\n\t"
"jnz 5f\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 6f)
"movl %[expect], %%eax\n\t"
"cmpl %%eax, %[v]\n\t"
"jnz 7f\n\t"
@@ -984,8 +982,7 @@ int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,
#endif
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
/* final store input */
[v] "m" (*v),
[expect] "m" (expect),
@@ -1034,15 +1031,15 @@ int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect,
"movl %[dst], %[rseq_scratch1]\n\t"
"movl %[len], %[rseq_scratch2]\n\t"
/* Start rseq by storing table entry pointer into rseq_cs. */
- RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_CS_OFFSET(%[rseq_abi]))
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 4f)
RSEQ_INJECT_ASM(3)
"movl %[expect], %%eax\n\t"
"cmpl %%eax, %[v]\n\t"
"jnz 5f\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
- RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_CPU_ID_OFFSET(%[rseq_abi]), 6f)
"movl %[expect], %%eax\n\t"
"cmpl %%eax, %[v]\n\t"
"jnz 7f\n\t"
@@ -1093,8 +1090,7 @@ int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect,
#endif
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
- [current_cpu_id] "m" (__rseq_abi.cpu_id),
- [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [rseq_abi] "r" (&__rseq_abi),
/* final store input */
[v] "m" (*v),
[expect] "m" (expect),

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