From 2f3f76fdb14a25fa27773bf415f61d7b10d53d62 Mon Sep 17 00:00:00 2001 From: David Blaikie Date: Thu, 21 Aug 2014 22:45:21 +0000 Subject: Use DILexicalBlockFile, rather than DILexicalBlock, to track discriminator changes to ensure discriminator changes don't introduce new DWARF DW_TAG_lexical_blocks. Somewhat unnoticed in the original implementation of discriminators, but it could cause instructions to end up in new, small, DW_TAG_lexical_blocks due to the use of DILexicalBlock to track discriminator changes. Instead, use DILexicalBlockFile which we already use to track file changes without introducing new scopes, so it works well to track discriminator changes in the same way. llvm-svn: 216239 --- llvm/docs/SourceLevelDebugging.rst | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) (limited to 'llvm/docs/SourceLevelDebugging.rst') diff --git a/llvm/docs/SourceLevelDebugging.rst b/llvm/docs/SourceLevelDebugging.rst index f76202ae053..f7b62cb0872 100644 --- a/llvm/docs/SourceLevelDebugging.rst +++ b/llvm/docs/SourceLevelDebugging.rst @@ -320,7 +320,6 @@ Block descriptors metadata, ;; Reference to context descriptor i32, ;; Line number i32, ;; Column number - i32, ;; DWARF path discriminator value i32 ;; Unique ID to identify blocks from a template function } @@ -334,6 +333,7 @@ lexical blocks at same depth. i32, ;; Tag = 11 (DW_TAG_lexical_block) metadata, ;; Source directory (including trailing slash) & file pair metadata ;; Reference to the scope we're annotating with a file change + i32, ;; DWARF path discriminator value } This descriptor provides a wrapper around a lexical scope to handle file @@ -733,8 +733,7 @@ Compiled to LLVM, this function would be represented like this: !15 = metadata !{i32 786688, metadata !16, metadata !"Z", metadata !5, i32 5, metadata !11, i32 0, i32 0} ; [ DW_TAG_auto_variable ] [Z] \ [line 5] - !16 = metadata !{i32 786443, metadata !1, metadata !4, i32 4, i32 0, i32 0, - i32 0} \ + !16 = metadata !{i32 786443, metadata !1, metadata !4, i32 4, i32 0, i32 0} \ ; [ DW_TAG_lexical_block ] [/private/tmp/t.c] !17 = metadata !{i32 5, i32 0, metadata !16, null} !18 = metadata !{i32 6, i32 0, metadata !16, null} @@ -786,8 +785,7 @@ scope information for the variable ``Z``. .. code-block:: llvm - !16 = metadata !{i32 786443, metadata !1, metadata !4, i32 4, i32 0, i32 0, - i32 0} + !16 = metadata !{i32 786443, metadata !1, metadata !4, i32 4, i32 0, i32 0} \ ; [ DW_TAG_lexical_block ] [/private/tmp/t.c] !17 = metadata !{i32 5, i32 0, metadata !16, null} -- cgit v1.2.3