[PATCH v2 07/10] ARM: mm: improve do_ldrd_abort macro
From: Russell King <hidden>
Date: 2015-08-25 15:41:52
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
Improve the do_ldrd_abort macro code - firstly, it inefficiently checks for the LDRD encoding by doing a multi-stage test of various bits. This can be simplified by generating a mask, bitmasking the instruction and then comparing the result. Secondly, we want to be able to test the result rather than branching to do_DataAbort, so remove the branch at the end and rename the macro to 'teq_ldrd' to reflect it's new usage. teq_ldrd macro returns 'eq' if the instruction was a LDRD. Signed-off-by: Russell King <redacted> --- arch/arm/mm/abort-ev5t.S | 3 ++- arch/arm/mm/abort-ev5tj.S | 3 ++- arch/arm/mm/abort-ev6.S | 3 ++- arch/arm/mm/abort-macro.S | 13 +++++-------- 4 files changed, 11 insertions(+), 11 deletions(-)
diff --git a/arch/arm/mm/abort-ev5t.S b/arch/arm/mm/abort-ev5t.S
index a0908d4653a3..c913031b79cc 100644
--- a/arch/arm/mm/abort-ev5t.S
+++ b/arch/arm/mm/abort-ev5t.S@@ -22,7 +22,8 @@ ENTRY(v5t_early_abort) do_thumb_abort fsr=r1, pc=r4, psr=r5, tmp=r3 ldreq r3, [r4] @ read aborted ARM instruction bic r1, r1, #1 << 11 @ clear bits 11 of FSR - do_ldrd_abort tmp=ip, insn=r3 + teq_ldrd tmp=ip, insn=r3 @ insn was LDRD? + beq do_DataAbort @ yes tst r3, #1 << 20 @ check write orreq r1, r1, #1 << 11 b do_DataAbort
diff --git a/arch/arm/mm/abort-ev5tj.S b/arch/arm/mm/abort-ev5tj.S
index 4006b7a61264..1b80d71adb0f 100644
--- a/arch/arm/mm/abort-ev5tj.S
+++ b/arch/arm/mm/abort-ev5tj.S@@ -24,7 +24,8 @@ ENTRY(v5tj_early_abort) bne do_DataAbort do_thumb_abort fsr=r1, pc=r4, psr=r5, tmp=r3 ldreq r3, [r4] @ read aborted ARM instruction - do_ldrd_abort tmp=ip, insn=r3 + teq_ldrd tmp=ip, insn=r3 @ insn was LDRD? + beq do_DataAbort @ yes tst r3, #1 << 20 @ L = 0 -> write orreq r1, r1, #1 << 11 @ yes. b do_DataAbort
diff --git a/arch/arm/mm/abort-ev6.S b/arch/arm/mm/abort-ev6.S
index 8c48c5c22a33..113704f30e9f 100644
--- a/arch/arm/mm/abort-ev6.S
+++ b/arch/arm/mm/abort-ev6.S@@ -34,7 +34,8 @@ ENTRY(v6_early_abort) ldr r3, [r4] @ read aborted ARM instruction ARM_BE8(rev r3, r3) - do_ldrd_abort tmp=ip, insn=r3 + teq_ldrd tmp=ip, insn=r3 @ insn was LDRD? + beq do_DataAbort @ yes tst r3, #1 << 20 @ L = 0 -> write orreq r1, r1, #1 << 11 @ yes. #endif
diff --git a/arch/arm/mm/abort-macro.S b/arch/arm/mm/abort-macro.S
index 2cbf68ef0e83..50d6c0a900b1 100644
--- a/arch/arm/mm/abort-macro.S
+++ b/arch/arm/mm/abort-macro.S@@ -29,12 +29,9 @@ not_thumb: * [7:4] == 1101 * [20] == 0 */ - .macro do_ldrd_abort, tmp, insn - tst \insn, #0x0e100000 @ [27:25,20] == 0 - bne not_ldrd - and \tmp, \insn, #0x000000f0 @ [7:4] == 1101 - cmp \tmp, #0x000000d0 - beq do_DataAbort -not_ldrd: + .macro teq_ldrd, tmp, insn + mov \tmp, #0x0e100000 + orr \tmp, #0x000000f0 + and \tmp, \insn, \tmp + teq \tmp, #0x000000d0 .endm -
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2.1.0