[llvm] [DWARF] Emit line 0 source locations for BB padding nops (PR #99496)

[Paul T Robinson via llvm-commits]

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@@ -1,11 +1,16 @@
-; RUN: llc -enable-fs-discriminator -improved-fs-discriminator=false < %s | FileCheck %s
-; RUN: llc -enable-fs-discriminator -improved-fs-discriminator=true < %s | FileCheck %s
+; RUN: llc -enable-fs-discriminator -improved-fs-discriminator=false < %s | FileCheck --implicit-check-not=.loc %s
+; RUN: llc -enable-fs-discriminator -improved-fs-discriminator=true < %s | FileCheck --implicit-check-not=.loc %s
 ;
 ; Check that fs-afdo discriminators are NOT generated, as debugInfoForProfiling is false (not set).
+; CHECK: .loc    1 7 15 prologue_end discriminator 2 # foo.c:7:15
 ; CHECK: .loc    1 7 3 is_stmt 0 discriminator 2 # foo.c:7:3
+; CHECK: .loc    1 0 3 # foo.c:0:3
 ; CHECK: .loc    1 9 5 is_stmt 1 discriminator 2 # foo.c:9:5
-; CHECK-NOT: .loc    1 9 5 is_stmt 0 discriminator
-; CHECK-NOT: .loc    1 7 3 is_stmt 1 discriminator
+; CHECK: .loc    1 0 0 is_stmt 0 # :0:0
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pogo59 wrote:

Setting the column to zero is sub-optimal, it requires extra line-table opcodes to set it to zero and then put it back. Please preserve the column number.

https://github.com/llvm/llvm-project/pull/99496