[llvm] [PowerPC] Do not rely on MachineSink threshold to optimize CR spilling (PR #128745)

[Guy David via llvm-commits]

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@@ -16,21 +16,21 @@
 
 define void @p9_setb_spill() {
 ; CHECK-P9-LABEL: p9_setb_spill:
-; CHECK-P9:       # %bb.1: # %if.then
+; CHECK-P9:       # %if.then
 ; CHECK-P9-DAG:    crnot 4*cr[[CREG:.*]]+lt, eq
 ; CHECK-P9-DAG:    setb [[REG1:.*]], cr[[CREG]]
 ; CHECK-P9-DAG:    stw [[REG1]]
 ; CHECK-P9:        blr
-; CHECK-P9:        .LBB0_4: # %if.then1
+; CHECK-P9:       # %if.then1
 ;
 ; CHECK-P8-LABEL: p9_setb_spill:
-; CHECK-P8:       # %bb.1: # %if.then
+; CHECK-P8:       # %if.then
 ; CHECK-P8-DAG:    crnot 4*cr[[CREG2:.*]]+lt, eq
 ; CHECK-P8-DAG:    mfocrf [[REG2:.*]],
 ; CHECK-P8-DAG:    rlwinm [[REG2]], [[REG2]]
 ; CHECK-P8-DAG:    stw [[REG2]]
 ; CHECK-P8:        blr
-; CHECK-P8:        .LBB0_4: # %if.then1
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guy-david wrote:

I thought I ought to remove the names of temporary blocks to make the test more "robust", but maybe doing so hides the fact that the test is invalid, reverted.
Added another simple test case.

https://github.com/llvm/llvm-project/pull/128745