Optimize Info Table Provenance Entries (IPEs) Map creation and lookupwip/IPE_hashmap

Using a hash map reduces the complexity of lookupIPE(), making it non linear.

On registration each IPE list is added to a temporary IPE lists buffer, reducing
registration time. The hash map is built lazily on first lookup.

IPE event output to stderr is added with tests.

For details, please see
Note [The Info Table Provenance Entry (IPE) Map].

A performance test for IPE registration and lookup can be found here:
https://gitlab.haskell.org/ghc/ghc/-/merge_requests/5724#note_370806

1 files changed, 42 insertions, 0 deletions

diff --git a/testsuite/tests/rts/ipeEventLog_lib.c b/testsuite/tests/rts/ipeEventLog_lib.c
new file mode 100644
index 0000000000..df54231fa7
--- /dev/null
+++ b/testsuite/tests/rts/ipeEventLog_lib.c
@@ -0,0 +1,42 @@
+#include "Rts.h"
+#include "rts/IPE.h"
+#include <string.h>
+
+InfoProvEnt *makeAnyProvEntry(Capability *cap, int i) {
+    HaskellObj fourtyTwo = rts_mkInt(cap, 42);
+
+    InfoProvEnt *provEnt = malloc(sizeof(InfoProvEnt));
+    provEnt->info = (StgInfoTable *)fourtyTwo->header.info;
+
+    unsigned int tableNameLength = strlen("table_name_") + 3 /* digits */ + 1 /* null character */;
+    char *tableName = malloc(sizeof(char) * tableNameLength);
+    snprintf(tableName, tableNameLength, "table_name_%03i", i);
+    provEnt->prov.table_name = tableName;
+
+    unsigned int closureDescLength = strlen("closure_desc_") + 3 /* digits */ + 1 /* null character */;
+    char *closureDesc = malloc(sizeof(char) * closureDescLength);
+    snprintf(closureDesc, closureDescLength, "closure_desc_%03i", i);
+    provEnt->prov.closure_desc = closureDesc;
+
+    unsigned int tyDescLength = strlen("ty_desc_") + 3 /* digits */ + 1 /* null character */;
+    char *tyDesc = malloc(sizeof(char) * tyDescLength);
+    snprintf(tyDesc, tyDescLength, "ty_desc_%03i", i);
+    provEnt->prov.ty_desc = tyDesc;
+
+    unsigned int labelLength = strlen("label_") + 3 /* digits */ + 1 /* null character */;
+    char *label = malloc(sizeof(char) * labelLength);
+    snprintf(label, labelLength, "label_%03i", i);
+    provEnt->prov.label = label;
+
+    unsigned int moduleLength = strlen("module_") + 3 /* digits */ + 1 /* null character */;
+    char *module = malloc(sizeof(char) * labelLength);
+    snprintf(module, moduleLength, "module_%03i", i);
+    provEnt->prov.module = module;
+
+    unsigned int srcLocLength = strlen("srcloc_") + 3 /* digits */ + 1 /* null character */;
+    char *srcLoc = malloc(sizeof(char) * srcLocLength);
+    snprintf(srcLoc, srcLocLength, "srcloc_%03i", i);
+    provEnt->prov.srcloc = srcLoc;
+
+    return provEnt;
+}