From 1acbf27e8a5843911d122ad0008e79ec5f7b6382 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Mon, 9 May 2022 07:36:01 +0200 Subject: [PATCH] powerpc/code-patching: Inline is_offset_in_{cond}_branch_range() Test in is_offset_in_branch_range() and is_offset_in_cond_branch_range() are simple tests that are worth inlining. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/a05be0ccb7373e6a9789a1988fcd0c810f5f9269.1652074503.git.christophe.leroy@csgroup.eu --- arch/powerpc/include/asm/code-patching.h | 29 +++++++++++++++++++++++++++-- arch/powerpc/lib/code-patching.c | 27 --------------------------- 2 files changed, 27 insertions(+), 29 deletions(-) diff --git a/arch/powerpc/include/asm/code-patching.h b/arch/powerpc/include/asm/code-patching.h index bccc3a5..378b705 100644 --- a/arch/powerpc/include/asm/code-patching.h +++ b/arch/powerpc/include/asm/code-patching.h @@ -24,8 +24,33 @@ DECLARE_STATIC_KEY_FALSE(init_mem_is_free); -bool is_offset_in_branch_range(long offset); -bool is_offset_in_cond_branch_range(long offset); +/* + * Powerpc branch instruction is : + * + * 0 6 30 31 + * +---------+----------------+---+---+ + * | opcode | LI |AA |LK | + * +---------+----------------+---+---+ + * Where AA = 0 and LK = 0 + * + * LI is a signed 24 bits integer. The real branch offset is computed + * by: imm32 = SignExtend(LI:'0b00', 32); + * + * So the maximum forward branch should be: + * (0x007fffff << 2) = 0x01fffffc = 0x1fffffc + * The maximum backward branch should be: + * (0xff800000 << 2) = 0xfe000000 = -0x2000000 + */ +static inline bool is_offset_in_branch_range(long offset) +{ + return (offset >= -0x2000000 && offset <= 0x1fffffc && !(offset & 0x3)); +} + +static inline bool is_offset_in_cond_branch_range(long offset) +{ + return offset >= -0x8000 && offset <= 0x7fff && !(offset & 0x3); +} + int create_branch(ppc_inst_t *instr, const u32 *addr, unsigned long target, int flags); int create_cond_branch(ppc_inst_t *instr, const u32 *addr, diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c index be670e1..13a5a38 100644 --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -214,33 +214,6 @@ int patch_branch(u32 *addr, unsigned long target, int flags) return patch_instruction(addr, instr); } -bool is_offset_in_branch_range(long offset) -{ - /* - * Powerpc branch instruction is : - * - * 0 6 30 31 - * +---------+----------------+---+---+ - * | opcode | LI |AA |LK | - * +---------+----------------+---+---+ - * Where AA = 0 and LK = 0 - * - * LI is a signed 24 bits integer. The real branch offset is computed - * by: imm32 = SignExtend(LI:'0b00', 32); - * - * So the maximum forward branch should be: - * (0x007fffff << 2) = 0x01fffffc = 0x1fffffc - * The maximum backward branch should be: - * (0xff800000 << 2) = 0xfe000000 = -0x2000000 - */ - return (offset >= -0x2000000 && offset <= 0x1fffffc && !(offset & 0x3)); -} - -bool is_offset_in_cond_branch_range(long offset) -{ - return offset >= -0x8000 && offset <= 0x7fff && !(offset & 0x3); -} - /* * Helper to check if a given instruction is a conditional branch * Derived from the conditional checks in analyse_instr() -- 2.7.4