Commit Graph

2 Commits

Author SHA1 Message Date
JF Bastien 5d3280c7a7 x86-32: PUSHF/POPF use/def EFLAGS
Summary: As a side-quest for D6629 jvoung pointed out that I should use -verify-machineinstrs and this found a bug in x86-32's handling of EFLAGS for PUSHF/POPF. This patch fixes the use/def, and adds -verify-machineinstrs to all x86 tests which contain 'EFLAGS'. One exception: this patch leaves inline-asm-fpstack.ll as-is because it fails -verify-machineinstrs in a way unrelated to EFLAGS. This patch also modifies cmpxchg-clobber-flags.ll along the lines of what D6629 already does by also testing i386.

Test Plan: ninja check

Reviewers: t.p.northover, jvoung

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D6687

llvm-svn: 224359
2014-12-16 20:15:45 +00:00
Tim Northover e4c7be56bf ScheduleDAG: record PhysReg dependencies represented by CopyFromReg nodes
x86's CMPXCHG -> EFLAGS consumer wasn't being recorded as a real EFLAGS
dependency because it was represented by a pair of CopyFromReg(EFLAGS) ->
CopyToReg(EFLAGS) nodes. ScheduleDAG was expecting the source to be an
implicit-def on the instruction, where the result numbers in the DAG and the
Uses list in TableGen matched up precisely.

The Copy notation seems much more robust, so this patch extends ScheduleDAG
rather than refactoring x86.

Should fix PR20376.

llvm-svn: 220529
2014-10-23 22:31:48 +00:00