Commit 651925a4 authored by Finkel, Hal's avatar Finkel, Hal
Browse files

Merging r223708: 

------------------------------------------------------------------------
r223708 | hfinkel | 2014-12-08 22:54:22 +0000 (Mon, 08 Dec 2014) | 13 lines

[PowerPC] Don't use a non-allocatable register to implement the 'cc' alias

GCC accepts 'cc' as an alias for 'cr0', and we need to do the same when
processing inline asm constraints. This had previously been implemented using a
non-allocatable register, named 'cc', that was listed as an alias of 'cr0', but
the infrastructure does not seem to support this properly (neither the register
allocator nor the scheduler properly accounts for the alias). Instead, we can
just process this as a naming alias inside of the inline asm
constraint-processing code, so we'll do that instead.

There are two regression tests, one where the post-RA scheduler did the wrong
thing with the non-allocatable alias, and one where the register allocator did
the wrong thing. Fixes PR21742.
------------------------------------------------------------------------

llvm-svn: 223748
parent 628944db

llvm/lib/Target/PowerPC/PPCISelLowering.cpp

+6 −0
Original line number Diff line number Diff line
@@ -8974,6 +8974,12 @@ PPCTargetLowering::getRegForInlineAsmConstraint(const std::string &Constraint, 
                          &PPC::G8RCRegClass);

  }



  // GCC accepts 'cc' as an alias for 'cr0', and we need to do the same.

  if (!R.second && StringRef("{cc}").equals_lower(Constraint)) {

    R.first = PPC::CR0;

    R.second = &PPC::CRRCRegClass;

  }



  return R;

}

llvm/lib/Target/PowerPC/PPCRegisterInfo.td

+0 −9
Original line number Diff line number Diff line
@@ -188,11 +188,6 @@ def CR6 : CR<6, "cr6", [CR6LT, CR6GT, CR6EQ, CR6UN]>, DwarfRegNum<[74, 74]>; 
def CR7 : CR<7, "cr7", [CR7LT, CR7GT, CR7EQ, CR7UN]>, DwarfRegNum<[75, 75]>;

}



// An alias for "cr0" used by GCC.

def CC : PPCReg<"cc">, DwarfRegAlias<CR0> {

  let Aliases = [CR0];

}



// Link register

def LR  : SPR<8, "lr">, DwarfRegNum<[-2, 65]>;

//let Aliases = [LR] in
@@ -306,7 +301,3 @@ def CARRYRC : RegisterClass<"PPC", [i32], 32, (add CARRY)> { 
  let CopyCost = -1;

}

def CCRC : RegisterClass<"PPC", [i32], 32, (add CC)> {

  let isAllocatable = 0;

}

llvm/test/CodeGen/PowerPC/subreg-postra-2.ll

0 → 100644
+175 −0
Original line number Diff line number Diff line 
; RUN: llc -mcpu=pwr7 < %s | FileCheck %s

target datalayout = "E-m:e-i64:64-n32:64"

target triple = "powerpc64-unknown-linux-gnu"



; Function Attrs: nounwind

define void @jbd2_journal_commit_transaction() #0 {

entry:

  br i1 undef, label %do.body, label %if.then5



if.then5:                                         ; preds = %entry

  unreachable



do.body:                                          ; preds = %entry

  br i1 undef, label %do.body.i, label %trace_jbd2_start_commit.exit



do.body.i:                                        ; preds = %do.body

  unreachable



trace_jbd2_start_commit.exit:                     ; preds = %do.body

  br i1 undef, label %do.body.i1116, label %trace_jbd2_commit_locking.exit



do.body.i1116:                                    ; preds = %trace_jbd2_start_commit.exit

  unreachable



trace_jbd2_commit_locking.exit:                   ; preds = %trace_jbd2_start_commit.exit

  br i1 undef, label %while.end, label %while.body.lr.ph



while.body.lr.ph:                                 ; preds = %trace_jbd2_commit_locking.exit

  unreachable



while.end:                                        ; preds = %trace_jbd2_commit_locking.exit

  br i1 undef, label %spin_unlock.exit1146, label %if.then.i.i.i.i1144



if.then.i.i.i.i1144:                              ; preds = %while.end

  unreachable



spin_unlock.exit1146:                             ; preds = %while.end

  br i1 undef, label %spin_unlock.exit1154, label %if.then.i.i.i.i1152



if.then.i.i.i.i1152:                              ; preds = %spin_unlock.exit1146

  unreachable



spin_unlock.exit1154:                             ; preds = %spin_unlock.exit1146

  br i1 undef, label %do.body.i1159, label %trace_jbd2_commit_flushing.exit



do.body.i1159:                                    ; preds = %spin_unlock.exit1154

  br i1 undef, label %if.end.i1166, label %do.body5.i1165



do.body5.i1165:                                   ; preds = %do.body.i1159

  unreachable



if.end.i1166:                                     ; preds = %do.body.i1159

  unreachable



trace_jbd2_commit_flushing.exit:                  ; preds = %spin_unlock.exit1154

  br i1 undef, label %for.end.i, label %for.body.lr.ph.i



for.body.lr.ph.i:                                 ; preds = %trace_jbd2_commit_flushing.exit

  unreachable



for.end.i:                                        ; preds = %trace_jbd2_commit_flushing.exit

  br i1 undef, label %journal_submit_data_buffers.exit, label %if.then.i.i.i.i31.i



if.then.i.i.i.i31.i:                              ; preds = %for.end.i

  br label %journal_submit_data_buffers.exit



journal_submit_data_buffers.exit:                 ; preds = %if.then.i.i.i.i31.i, %for.end.i

  br i1 undef, label %if.end103, label %if.then102



if.then102:                                       ; preds = %journal_submit_data_buffers.exit

  unreachable



if.end103:                                        ; preds = %journal_submit_data_buffers.exit

  br i1 undef, label %do.body.i1182, label %trace_jbd2_commit_logging.exit



do.body.i1182:                                    ; preds = %if.end103

  br i1 undef, label %if.end.i1189, label %do.body5.i1188



do.body5.i1188:                                   ; preds = %do.body5.i1188, %do.body.i1182

  br i1 undef, label %if.end.i1189, label %do.body5.i1188



if.end.i1189:                                     ; preds = %do.body5.i1188, %do.body.i1182

  unreachable



trace_jbd2_commit_logging.exit:                   ; preds = %if.end103

  br label %while.cond129.outer1451



while.cond129.outer1451:                          ; preds = %start_journal_io, %trace_jbd2_commit_logging.exit

  br label %while.cond129



while.cond129:                                    ; preds = %if.then135, %while.cond129.outer1451

  br i1 undef, label %while.end246, label %if.then135



if.then135:                                       ; preds = %while.cond129

  br i1 undef, label %start_journal_io, label %while.cond129



start_journal_io:                                 ; preds = %if.then135

  br label %while.cond129.outer1451



while.end246:                                     ; preds = %while.cond129

  br i1 undef, label %for.end.i1287, label %for.body.i1277



for.body.i1277:                                   ; preds = %while.end246

  unreachable



for.end.i1287:                                    ; preds = %while.end246

  br i1 undef, label %journal_finish_inode_data_buffers.exit, label %if.then.i.i.i.i84.i



if.then.i.i.i.i84.i:                              ; preds = %for.end.i1287

  unreachable



journal_finish_inode_data_buffers.exit:           ; preds = %for.end.i1287

  br i1 undef, label %if.end256, label %if.then249



if.then249:                                       ; preds = %journal_finish_inode_data_buffers.exit

  unreachable



if.end256:                                        ; preds = %journal_finish_inode_data_buffers.exit

  br label %while.body318



while.body318:                                    ; preds = %wait_on_buffer.exit, %if.end256

  br i1 undef, label %wait_on_buffer.exit, label %if.then.i1296



if.then.i1296:                                    ; preds = %while.body318

  br label %wait_on_buffer.exit



wait_on_buffer.exit:                              ; preds = %if.then.i1296, %while.body318

  br i1 undef, label %do.body378, label %while.body318



do.body378:                                       ; preds = %wait_on_buffer.exit

  br i1 undef, label %while.end418, label %while.body392.lr.ph



while.body392.lr.ph:                              ; preds = %do.body378

  br label %while.body392



while.body392:                                    ; preds = %wait_on_buffer.exit1319, %while.body392.lr.ph

  %0 = load i8** undef, align 8

  %add.ptr399 = getelementptr inbounds i8* %0, i64 -72

  %b_state.i.i1314 = bitcast i8* %add.ptr399 to i64*

  %tobool.i1316 = icmp eq i64 undef, 0

  br i1 %tobool.i1316, label %wait_on_buffer.exit1319, label %if.then.i1317



if.then.i1317:                                    ; preds = %while.body392

  unreachable



wait_on_buffer.exit1319:                          ; preds = %while.body392

  %1 = load volatile i64* %b_state.i.i1314, align 8

  %conv.i.i1322 = and i64 %1, 1

  %lnot404 = icmp eq i64 %conv.i.i1322, 0

  %.err.4 = select i1 %lnot404, i32 -5, i32 undef

  %2 = call i64 asm sideeffect "1:.long 0x7c0000a8 $| ((($0) & 0x1f) << 21) $| (((0) & 0x1f) << 16) $| ((($3) & 0x1f) << 11) $| (((0) & 0x1) << 0) \0Aandc $0,$0,$2\0Astdcx. $0,0,$3\0Abne- 1b\0A", "=&r,=*m,r,r,*m,~{cc},~{memory}"(i64* %b_state.i.i1314, i64 262144, i64* %b_state.i.i1314, i64* %b_state.i.i1314) #0

  store i8* %0, i8** undef, align 8

  %cmp.i1312 = icmp eq i32* undef, undef

  br i1 %cmp.i1312, label %while.end418, label %while.body392



while.end418:                                     ; preds = %wait_on_buffer.exit1319, %do.body378

  %err.4.lcssa = phi i32 [ undef, %do.body378 ], [ %.err.4, %wait_on_buffer.exit1319 ]

  %tobool419 = icmp eq i32 %err.4.lcssa, 0

  br i1 %tobool419, label %if.end421, label %if.then420



; CHECK-LABEL: @jbd2_journal_commit_transaction

; CHECK: andi.

; CHECK: cror [[REG:[0-9]+]], 1, 1

; CHECK: stdcx.

; CHECK: isel {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}, [[REG]]



if.then420:                                       ; preds = %while.end418

  unreachable



if.end421:                                        ; preds = %while.end418

  unreachable

}



attributes #0 = { nounwind }

llvm/test/CodeGen/PowerPC/subreg-postra.ll

0 → 100644
+168 −0
Original line number Diff line number Diff line 
; RUN: llc -mcpu=pwr7 < %s | FileCheck %s

target datalayout = "E-m:e-i64:64-n32:64"

target triple = "powerpc64-unknown-linux-gnu"



; Function Attrs: nounwind

define void @jbd2_journal_commit_transaction(i32* %journal) #0 {

entry:

  br i1 undef, label %do.body, label %if.then5



if.then5:                                         ; preds = %entry

  unreachable



do.body:                                          ; preds = %entry

  br i1 undef, label %do.body.i, label %trace_jbd2_start_commit.exit



do.body.i:                                        ; preds = %do.body

  unreachable



trace_jbd2_start_commit.exit:                     ; preds = %do.body

  br i1 undef, label %do.body.i1116, label %trace_jbd2_commit_locking.exit



do.body.i1116:                                    ; preds = %trace_jbd2_start_commit.exit

  br i1 undef, label %if.end.i1123, label %do.body5.i1122



do.body5.i1122:                                   ; preds = %do.body.i1116

  unreachable



if.end.i1123:                                     ; preds = %do.body.i1116

  br label %trace_jbd2_commit_locking.exit



trace_jbd2_commit_locking.exit:                   ; preds = %if.end.i1123, %trace_jbd2_start_commit.exit

  br i1 undef, label %spin_unlock.exit1146, label %if.then.i.i.i.i1144



if.then.i.i.i.i1144:                              ; preds = %trace_jbd2_commit_locking.exit

  unreachable



spin_unlock.exit1146:                             ; preds = %trace_jbd2_commit_locking.exit

  br i1 undef, label %spin_unlock.exit1154, label %if.then.i.i.i.i1152



if.then.i.i.i.i1152:                              ; preds = %spin_unlock.exit1146

  br label %spin_unlock.exit1154



spin_unlock.exit1154:                             ; preds = %if.then.i.i.i.i1152, %spin_unlock.exit1146

  br i1 undef, label %do.body.i1159, label %trace_jbd2_commit_flushing.exit



do.body.i1159:                                    ; preds = %spin_unlock.exit1154

  unreachable



trace_jbd2_commit_flushing.exit:                  ; preds = %spin_unlock.exit1154

  br i1 undef, label %for.end.i, label %for.body.lr.ph.i



for.body.lr.ph.i:                                 ; preds = %trace_jbd2_commit_flushing.exit

  br i1 undef, label %spin_unlock.exit.i, label %if.then.i.i.i.i.i



if.then.i.i.i.i.i:                                ; preds = %for.body.lr.ph.i

  unreachable



spin_unlock.exit.i:                               ; preds = %for.body.lr.ph.i

  unreachable



for.end.i:                                        ; preds = %trace_jbd2_commit_flushing.exit

  br i1 undef, label %journal_submit_data_buffers.exit, label %if.then.i.i.i.i31.i



if.then.i.i.i.i31.i:                              ; preds = %for.end.i

  unreachable



journal_submit_data_buffers.exit:                 ; preds = %for.end.i

  br i1 undef, label %if.end103, label %if.then102



if.then102:                                       ; preds = %journal_submit_data_buffers.exit

  unreachable



if.end103:                                        ; preds = %journal_submit_data_buffers.exit

  br i1 undef, label %do.body.i1182, label %trace_jbd2_commit_logging.exit



do.body.i1182:                                    ; preds = %if.end103

  unreachable



trace_jbd2_commit_logging.exit:                   ; preds = %if.end103

  br i1 undef, label %for.end.i1287, label %for.body.i1277



for.body.i1277:                                   ; preds = %trace_jbd2_commit_logging.exit

  unreachable



for.end.i1287:                                    ; preds = %trace_jbd2_commit_logging.exit

  br i1 undef, label %journal_finish_inode_data_buffers.exit, label %if.then.i.i.i.i84.i



if.then.i.i.i.i84.i:                              ; preds = %for.end.i1287

  unreachable



journal_finish_inode_data_buffers.exit:           ; preds = %for.end.i1287

  br i1 undef, label %if.end256, label %if.then249



if.then249:                                       ; preds = %journal_finish_inode_data_buffers.exit

  unreachable



if.end256:                                        ; preds = %journal_finish_inode_data_buffers.exit

  br i1 undef, label %do.body277, label %if.then260



if.then260:                                       ; preds = %if.end256

  br label %do.body277



do.body277:                                       ; preds = %if.then260, %if.end256

  br label %while.body318



while.body318:                                    ; preds = %wait_on_buffer.exit, %do.body277

  %tobool.i1295 = icmp eq i64 undef, 0

  br i1 %tobool.i1295, label %wait_on_buffer.exit, label %if.then.i1296



if.then.i1296:                                    ; preds = %while.body318

  unreachable



wait_on_buffer.exit:                              ; preds = %while.body318

  br i1 undef, label %do.body378, label %while.body318



do.body378:                                       ; preds = %wait_on_buffer.exit

  br i1 undef, label %while.end418, label %while.body392.lr.ph



while.body392.lr.ph:                              ; preds = %do.body378

  br label %while.body392



while.body392:                                    ; preds = %wait_on_buffer.exit1319, %while.body392.lr.ph

  %0 = load i8** undef, align 8

  %add.ptr399 = getelementptr inbounds i8* %0, i64 -72

  %b_state.i.i1314 = bitcast i8* %add.ptr399 to i64*

  %tobool.i1316 = icmp eq i64 undef, 0

  br i1 %tobool.i1316, label %wait_on_buffer.exit1319, label %if.then.i1317



if.then.i1317:                                    ; preds = %while.body392

  unreachable



wait_on_buffer.exit1319:                          ; preds = %while.body392

  %1 = load volatile i64* %b_state.i.i1314, align 8

  %conv.i.i1322 = and i64 %1, 1

  %lnot404 = icmp eq i64 %conv.i.i1322, 0

  %.err.4 = select i1 %lnot404, i32 -5, i32 undef

  %2 = call i64 asm sideeffect "1:.long 0x7c0000a8 $| ((($0) & 0x1f) << 21) $| (((0) & 0x1f) << 16) $| ((($3) & 0x1f) << 11) $| (((0) & 0x1) << 0) \0Aandc $0,$0,$2\0Astdcx. $0,0,$3\0Abne- 1b\0A", "=&r,=*m,r,r,*m,~{cc},~{memory}"(i64* %b_state.i.i1314, i64 262144, i64* %b_state.i.i1314, i64* %b_state.i.i1314) #1

  %prev.i.i.i1325 = getelementptr inbounds i8* %0, i64 8

  %3 = load i32** null, align 8

  store i32* %3, i32** undef, align 8

  call void @__brelse(i32* undef) #1

  br i1 undef, label %while.end418, label %while.body392



; CHECK-LABEL: @jbd2_journal_commit_transaction

; CHECK: andi.

; CHECK: cror [[REG:[0-9]+]], 1, 1

; CHECK: stdcx.

; CHECK: isel {{[0-9]+}}, {{[0-9]+}}, {{[0-9]+}}, [[REG]]



while.end418:                                     ; preds = %wait_on_buffer.exit1319, %do.body378

  %err.4.lcssa = phi i32 [ undef, %do.body378 ], [ %.err.4, %wait_on_buffer.exit1319 ]

  br i1 undef, label %if.end421, label %if.then420



if.then420:                                       ; preds = %while.end418

  call void @jbd2_journal_abort(i32* %journal, i32 signext %err.4.lcssa) #1

  br label %if.end421



if.end421:                                        ; preds = %if.then420, %while.end418

  unreachable

}



declare void @jbd2_journal_abort(i32*, i32 signext)



declare void @__brelse(i32*)



attributes #0 = { nounwind }

attributes #1 = { nounwind }