; RUN: llc < %s -march=x86 -disable-block-placement | FileCheck %s ; ; Test RegistersDefinedFromSameValue. We have multiple copies of the same vreg: ; while.body85.i: ; vreg1 = copy vreg2 ; vreg2 = add ; critical edge from land.lhs.true.i -> if.end117.i: ; vreg27 = vreg2 ; critical edge from land.lhs.true103.i -> if.end117.i: ; vreg27 = vreg2 ; if.then108.i: ; vreg27 = vreg1 ; ; Prior to fixing PR10920 401.bzip miscompile, the coalescer would ; consider vreg1 and vreg27 to be copies of the same value. It would ; then remove one of the critical edge copes, which cannot safely be removed. ; There are two obvious ways the register-allocator could go here, either ; reusing the pre-addition register later, or the post-addition one. Currently, ; it does the latter, so we check: ; CHECK: # %while.body85.i ; CHECK-NOT: # % ; CHECK-NOT: add ; CHECK: movl %[[POSTR:e[abcdxi]+]], %[[PRER:e[abcdxi]+]] ; CHECK: addl %{{.*}}, %[[POSTR]] ; CHECK: # %while.end.i ; CHECK-NOT: movl %[[POSTR]] ; CHECK: # %land.lhs.true.i ; CHECK-NOT: movl %[[POSTR]] ; CHECK: # %land.lhs.true103.i ; CHECK-NOT: movl %[[POSTR]] ; CHECK: # %if.then108.i ; CHECK: movl %[[PRER]], %[[POSTR]] ; CHECK: # %if.end117.i ; and use it for fprintf: ; CHECK: movl %[[POSTR]], 12(%esp) ; If it ever reverts to reusing the pre-addition register then we should ; *probably* check this instead (it certainly worked last time): ; CHECKALT: # %while.body85.i ; CHECKALT-NOT: # % ; CHECKALT-NOT: add ; CHECKALT: movl %[[POSTR:e[abcdxi]+]], %[[PRER:e[abcdxi]+]] ; CHECKALT: addl %{{.*}}, %[[POSTR]] ; CHECKALT: # %while.end.i ; CHECKALT: movl %[[POSTR]], %[[USER:e[abcdxi]+]] ; CHECKALT: # %land.lhs.true.i ; CHECKALT: movl %[[POSTR]], %[[USER]] ; CHECKALT: # %land.lhs.true103.i ; CHECKALT: movl %[[POSTR]], %[[USER]] ; CHECKALT: # %if.then108.i ; [[PRER] live out, so nothing on this path should define it. ; CHECKALT-NOT: , %[[PRER]] ; CHECKALT: # %if.end117.i target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-n8:16:32" @.str3 = external unnamed_addr constant [59 x i8], align 1 define void @BZ2_compressBlock() nounwind ssp { entry: br i1 undef, label %if.then68, label %if.end85 if.then68: ; preds = %entry br label %for.body.i.i for.body.i.i: ; preds = %for.inc.i.i, %if.then68 br i1 undef, label %for.inc.i.i, label %if.then.i.i if.then.i.i: ; preds = %for.body.i.i br label %for.inc.i.i for.inc.i.i: ; preds = %if.then.i.i, %for.body.i.i br i1 undef, label %makeMaps_e.exit.i, label %for.body.i.i makeMaps_e.exit.i: ; preds = %for.inc.i.i br i1 undef, label %for.cond19.preheader.i, label %for.cond.for.cond19.preheader_crit_edge.i for.cond.for.cond19.preheader_crit_edge.i: ; preds = %makeMaps_e.exit.i unreachable for.cond19.preheader.i: ; preds = %makeMaps_e.exit.i br i1 undef, label %for.body25.lr.ph.i, label %for.cond33.preheader.i for.body25.lr.ph.i: ; preds = %for.cond19.preheader.i br label %for.body25.i for.cond33.preheader.i: ; preds = %for.body25.i, %for.cond19.preheader.i br i1 undef, label %if.then.i, label %if.end.i for.body25.i: ; preds = %for.body25.i, %for.body25.lr.ph.i br i1 undef, label %for.body25.i, label %for.cond33.preheader.i if.then.i: ; preds = %for.cond33.preheader.i br label %if.end.i if.end.i: ; preds = %if.then.i, %for.cond33.preheader.i br i1 undef, label %for.inc27.us.5.i, label %for.end30.i for.end30.i: ; preds = %for.inc27.us.5.i, %if.end.i br i1 undef, label %if.end36.i, label %if.then35.i if.then35.i: ; preds = %for.end30.i unreachable if.end36.i: ; preds = %for.end30.i %sub83.i = add nsw i32 undef, 1 br label %while.body.i188 for.cond182.preheader.i: ; preds = %for.end173.i br i1 undef, label %for.inc220.us.i, label %while.body300.preheader.i while.body.i188: ; preds = %for.end173.i, %if.end36.i %gs.0526.i = phi i32 [ 0, %if.end36.i ], [ %add177.i, %for.end173.i ] %or.cond514517.i = and i1 false, undef br i1 %or.cond514517.i, label %while.body85.i, label %if.end117.i while.body85.i: ; preds = %while.body85.i, %while.body.i188 %aFreq.0518.i = phi i32 [ %add93.i, %while.body85.i ], [ 0, %while.body.i188 ] %inc87.i = add nsw i32 0, 1 %tmp91.i = load i32, i32* undef, align 4 %add93.i = add nsw i32 %tmp91.i, %aFreq.0518.i %or.cond514.i = and i1 undef, false br i1 %or.cond514.i, label %while.body85.i, label %while.end.i while.end.i: ; preds = %while.body85.i br i1 undef, label %land.lhs.true.i, label %if.end117.i land.lhs.true.i: ; preds = %while.end.i br i1 undef, label %land.lhs.true103.i, label %if.end117.i land.lhs.true103.i: ; preds = %land.lhs.true.i br i1 undef, label %if.then108.i, label %if.end117.i if.then108.i: ; preds = %land.lhs.true103.i br label %if.end117.i if.end117.i: ; preds = %if.then108.i, %land.lhs.true103.i, %land.lhs.true.i, %while.end.i, %while.body.i188 %aFreq.1.i = phi i32 [ %aFreq.0518.i, %if.then108.i ], [ %add93.i, %land.lhs.true103.i ], [ %add93.i, %land.lhs.true.i ], [ %add93.i, %while.end.i ], [ 0, %while.body.i188 ] %ge.1.i = phi i32 [ 0, %if.then108.i ], [ %inc87.i, %land.lhs.true103.i ], [ %inc87.i, %land.lhs.true.i ], [ %inc87.i, %while.end.i ], [ 0, %while.body.i188 ] br i1 undef, label %if.then122.i, label %for.cond138.preheader.i if.then122.i: ; preds = %if.end117.i call void (...) @fprintf(i32 undef, i32 %gs.0526.i, i32 %ge.1.i, i32 %aFreq.1.i, double undef) nounwind br label %for.cond138.preheader.i for.cond138.preheader.i: ; preds = %if.then122.i, %if.end117.i br i1 undef, label %for.body143.lr.ph.i, label %for.end173.i for.body143.lr.ph.i: ; preds = %for.cond138.preheader.i br label %for.body143.i for.body143.i: ; preds = %for.body143.i, %for.body143.lr.ph.i br i1 undef, label %for.end173.i, label %for.body143.i for.end173.i: ; preds = %for.body143.i, %for.cond138.preheader.i %add177.i = add nsw i32 %ge.1.i, 1 %cmp73.i = icmp sgt i32 undef, 0 br i1 %cmp73.i, label %while.body.i188, label %for.cond182.preheader.i for.inc220.us.i: ; preds = %for.cond182.preheader.i unreachable while.body300.preheader.i: ; preds = %for.cond182.preheader.i br i1 undef, label %for.end335.i, label %while.end2742.i for.end335.i: ; preds = %for.end2039.i, %while.body300.preheader.i br label %for.body2021.i for.body2021.i: ; preds = %for.body2021.i, %for.end335.i br i1 undef, label %for.body2021.i, label %for.end2039.i for.end2039.i: ; preds = %for.body2021.i br label %for.end335.i while.end2742.i: ; preds = %while.body300.preheader.i br i1 undef, label %if.then2748.i, label %for.body2778.i if.then2748.i: ; preds = %while.end2742.i unreachable for.body2778.i: ; preds = %while.end2742.i unreachable for.inc27.us.5.i: ; preds = %if.end.i br label %for.end30.i if.end85: ; preds = %entry ret void } declare void @fprintf(...) nounwind