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| author | Catalin Marinas <catalin.marinas@arm.com> | 2007-09-25 15:21:00 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2007-10-12 23:43:22 +0100 |
| commit | c1f438f5eec867707022e5f33bec5e91ec12f6e7 (patch) | |
| tree | cd10301fad4a855d59defcce878eee2e15e0cee5 /arch/arm/nwfpe | |
| parent | ec6b1482265ec8430fc38c79205567c3601d8901 (diff) | |
| download | linux-c1f438f5eec867707022e5f33bec5e91ec12f6e7.tar.gz linux-c1f438f5eec867707022e5f33bec5e91ec12f6e7.tar.bz2 linux-c1f438f5eec867707022e5f33bec5e91ec12f6e7.zip | |
[ARM] 4581/1: Fix the conditional execution of the NWFPE instructions
Starting with ARMv7-A, conditional execution of undefined instructions
can trigger an exception even if the condition check fails. This patch
modifies the NWFPE support to check the condition before emulating the
instruction.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/nwfpe')
| -rw-r--r-- | arch/arm/nwfpe/entry.S | 25 |
1 files changed, 14 insertions, 11 deletions
diff --git a/arch/arm/nwfpe/entry.S b/arch/arm/nwfpe/entry.S index 1dc13bc6d810..48bca0db4607 100644 --- a/arch/arm/nwfpe/entry.S +++ b/arch/arm/nwfpe/entry.S @@ -70,13 +70,24 @@ floating point instructions. GCC attempts to group floating point instructions to allow the emulator to spread the cost of the trap over several floating point instructions. */ +#include <asm/asm-offsets.h> + .globl nwfpe_enter nwfpe_enter: mov r4, lr @ save the failure-return addresses mov sl, sp @ we access the registers via 'sl' - ldr r5, [sp, #60] @ get contents of PC; + ldr r5, [sp, #S_PC] @ get contents of PC; + mov r6, r0 @ save the opcode emulate: + ldr r1, [sp, #S_PSR] @ fetch the PSR + bl checkCondition @ check the condition + cmp r0, #0 @ r0 = 0 ==> condition failed + + @ if condition code failed to match, next insn + beq next @ get the next instruction; + + mov r0, r6 @ prepare for EmulateAll() bl EmulateAll @ emulate the instruction cmp r0, #0 @ was emulation successful moveq pc, r4 @ no, return failure @@ -91,18 +102,10 @@ next: teqne r2, #0x0E000000 movne pc, r9 @ return ok if not a fp insn - str r5, [sp, #60] @ update PC copy in regs + str r5, [sp, #S_PC] @ update PC copy in regs mov r0, r6 @ save a copy - ldr r1, [sp, #64] @ fetch the condition codes - bl checkCondition @ check the condition - cmp r0, #0 @ r0 = 0 ==> condition failed - - @ if condition code failed to match, next insn - beq next @ get the next instruction; - - mov r0, r6 @ prepare for EmulateAll() - b emulate @ if r0 != 0, goto EmulateAll + b emulate @ check condition and emulate @ We need to be prepared for the instructions at .Lx1 and .Lx2 @ to fault. Emit the appropriate exception gunk to fix things up. |