From 78524bda5606e1b60615f57ebd6bfe5bcdd71afb Mon Sep 17 00:00:00 2001 From: Gabe Black Date: Tue, 19 Dec 2017 23:14:34 -0800 Subject: alpha,arm,mips,power,riscv,sparc,x86,cpu: Get rid of ISA_HAS_DELAY_SLOT. This constant is, first, a #define, and second only used in one place. In that one place, it appears that the code it guards is no longer necessary in general. It was originally written to avoid refetching a block of data that you're still in, even if you've moved slightly farther in it because you're skipping the next instruction due to an annulled branch delay slot. In reality however, in SPARC, the one ISA I'm aware of which has this sort of branching behavior, the PC state object will correctly determine that no branch is happening in these cases. Code lower down in the loop will then recompute where fetching should continue based on the next PC, automatically skipping the annulled branch slot without misinterpretting the gap as a branch. This change therefore also removes this block of code. Change-Id: I820ebc9df10aeb4fcb69c12f6a784e9ec616743c Reviewed-on: https://gem5-review.googlesource.com/6821 Reviewed-by: Andreas Sandberg Maintainer: Andreas Sandberg --- src/arch/alpha/isa_traits.hh | 3 --- 1 file changed, 3 deletions(-) (limited to 'src/arch/alpha') diff --git a/src/arch/alpha/isa_traits.hh b/src/arch/alpha/isa_traits.hh index 54b8003be..61688b5c8 100644 --- a/src/arch/alpha/isa_traits.hh +++ b/src/arch/alpha/isa_traits.hh @@ -45,9 +45,6 @@ using namespace LittleEndianGuest; StaticInstPtr decodeInst(ExtMachInst); -// Alpha Does NOT have a delay slot -#define ISA_HAS_DELAY_SLOT 0 - const Addr PageShift = 13; const Addr PageBytes = ULL(1) << PageShift; const Addr PageMask = ~(PageBytes - 1); -- cgit v1.2.3