[PATCH v2] ARM: kprobes: test-thumb: fix for LLVM_IAS=1

From: Nick Desaulniers
Date: Mon Mar 29 2021 - 18:13:08 EST


There's a few instructions that GAS infers operands but Clang doesn't;
from what I can tell the Arm ARM doesn't say these are optional.

F5.1.257 TBB, TBH T1 Halfword variant
F5.1.238 STREXD T1 variant
F5.1.84 LDREXD T1 variant

Link: https://github.com/ClangBuiltLinux/linux/issues/1309
Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
---
See:
https://lore.kernel.org/linux-arm-kernel/CAMj1kXE5uw4+zV3JVpfA2drOD5TZVMs5a_E5wrrnzjEYc=E_fA@xxxxxxxxxxxxxx/
for what I'd consider V1. The previous issues with .w suffixes have been
fixed or have fixes pending in LLVM:
* BL+DBG: https://reviews.llvm.org/D97236
* ORN/ORNS: https://reviews.llvm.org/D99538
* RSB/RSBS: https://reviews.llvm.org/D99542
I'd have expected the Arm ARM to use curly braces to denote optional
operands (see also "F5.1.167 RSB, RSBS (register)" for an example).

arch/arm/probes/kprobes/test-thumb.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/arm/probes/kprobes/test-thumb.c b/arch/arm/probes/kprobes/test-thumb.c
index 456c181a7bfe..4e11f0b760f8 100644
--- a/arch/arm/probes/kprobes/test-thumb.c
+++ b/arch/arm/probes/kprobes/test-thumb.c
@@ -441,21 +441,21 @@ void kprobe_thumb32_test_cases(void)
"3: mvn r0, r0 \n\t"
"2: nop \n\t")

- TEST_RX("tbh [pc, r",7, (9f-(1f+4))>>1,"]",
+ TEST_RX("tbh [pc, r",7, (9f-(1f+4))>>1,", lsl #1]",
"9: \n\t"
".short (2f-1b-4)>>1 \n\t"
".short (3f-1b-4)>>1 \n\t"
"3: mvn r0, r0 \n\t"
"2: nop \n\t")

- TEST_RX("tbh [pc, r",12, ((9f-(1f+4))>>1)+1,"]",
+ TEST_RX("tbh [pc, r",12, ((9f-(1f+4))>>1)+1,", lsl #1]",
"9: \n\t"
".short (2f-1b-4)>>1 \n\t"
".short (3f-1b-4)>>1 \n\t"
"3: mvn r0, r0 \n\t"
"2: nop \n\t")

- TEST_RRX("tbh [r",1,9f, ", r",14,1,"]",
+ TEST_RRX("tbh [r",1,9f, ", r",14,1,", lsl #1]",
"9: \n\t"
".short (2f-1b-4)>>1 \n\t"
".short (3f-1b-4)>>1 \n\t"
@@ -468,10 +468,10 @@ void kprobe_thumb32_test_cases(void)

TEST_UNSUPPORTED("strexb r0, r1, [r2]")
TEST_UNSUPPORTED("strexh r0, r1, [r2]")
- TEST_UNSUPPORTED("strexd r0, r1, [r2]")
+ TEST_UNSUPPORTED("strexd r0, r1, r2, [r2]")
TEST_UNSUPPORTED("ldrexb r0, [r1]")
TEST_UNSUPPORTED("ldrexh r0, [r1]")
- TEST_UNSUPPORTED("ldrexd r0, [r1]")
+ TEST_UNSUPPORTED("ldrexd r0, r1, [r1]")

TEST_GROUP("Data-processing (shifted register) and (modified immediate)")

--
2.31.0.291.g576ba9dcdaf-goog