Commit 296cfb88 authored by Committed by Joel BrobeckerBrowse files
s390: Fix BC instruction breakpoint handling
This fixes a long-lived bug in the s390 port. When trying to step over a breakpoint set on a BC (branch on condition) instruction with displaced stepping on IBM Z, gdb would incorrectly adjust the pc regardless of whether or not the branch was taken. Since the branch target is an absolute address, this would cause the inferior to jump around wildly whenever the branch was taken, either crashing it or causing it to behave unpredictably. It turns out that the logic to handle BC instructions correctly was in the code, but that the enum value representing its opcode has always been incorrect. This patch corrects the enum value to the actual opcode, fixing the stepping problem. The enum value is also used in the prologue analysis code, so this also fixes a minor bug where more of the prologue would be read than was necessary. gdb/ChangeLog: PR breakpoints/27009 * s390-tdep.h (op_bc): Correct BC opcode value.
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