1 files changed, 83 insertions, 0 deletions
diff --git a/tools/perf/arch/x86/util/perf_regs.c b/tools/perf/arch/x86/util/perf_regs.c
index c5db14f36cc7..09a7f556dc7c 100644
--- a/tools/perf/arch/x86/util/perf_regs.c
+++ b/tools/perf/arch/x86/util/perf_regs.c
@@ -1,4 +1,7 @@
+#include <string.h>
+
 #include "../../perf.h"
+#include "../../util/util.h"
 #include "../../util/perf_regs.h"
 
 const struct sample_reg sample_reg_masks[] = {
@@ -26,3 +29,83 @@ const struct sample_reg sample_reg_masks[] = {
 #endif
 	SMPL_REG_END
 };
+
+struct sdt_name_reg {
+	const char *sdt_name;
+	const char *uprobe_name;
+};
+#define SDT_NAME_REG(n, m) {.sdt_name = "%" #n, .uprobe_name = "%" #m}
+#define SDT_NAME_REG_END {.sdt_name = NULL, .uprobe_name = NULL}
+
+static const struct sdt_name_reg sdt_reg_renamings[] = {
+	SDT_NAME_REG(eax, ax),
+	SDT_NAME_REG(rax, ax),
+	SDT_NAME_REG(ebx, bx),
+	SDT_NAME_REG(rbx, bx),
+	SDT_NAME_REG(ecx, cx),
+	SDT_NAME_REG(rcx, cx),
+	SDT_NAME_REG(edx, dx),
+	SDT_NAME_REG(rdx, dx),
+	SDT_NAME_REG(esi, si),
+	SDT_NAME_REG(rsi, si),
+	SDT_NAME_REG(edi, di),
+	SDT_NAME_REG(rdi, di),
+	SDT_NAME_REG(ebp, bp),
+	SDT_NAME_REG(rbp, bp),
+	SDT_NAME_REG_END,
+};
+
+int sdt_rename_register(char **pdesc, char *old_name)
+{
+	const struct sdt_name_reg *rnames = sdt_reg_renamings;
+	char *new_desc, *old_desc = *pdesc;
+	size_t prefix_len, sdt_len, uprobe_len, old_desc_len, offset;
+	int ret = -1;
+
+	while (ret != 0 && rnames->sdt_name != NULL) {
+		sdt_len = strlen(rnames->sdt_name);
+		ret = strncmp(old_name, rnames->sdt_name, sdt_len);
+		rnames += !!ret;
+	}
+
+	if (rnames->sdt_name == NULL)
+		return 0;
+
+	sdt_len = strlen(rnames->sdt_name);
+	uprobe_len = strlen(rnames->uprobe_name);
+	old_desc_len = strlen(old_desc) + 1;
+
+	new_desc = zalloc(old_desc_len + uprobe_len - sdt_len);
+	if (new_desc == NULL)
+		return -1;
+
+	/* Copy the chars before the register name (at least '%') */
+	prefix_len = old_name - old_desc;
+	memcpy(new_desc, old_desc, prefix_len);
+
+	/* Copy the new register name */
+	memcpy(new_desc + prefix_len, rnames->uprobe_name, uprobe_len);
+
+	/* Copy the chars after the register name (if need be) */
+	offset = prefix_len + sdt_len;
+	if (offset < old_desc_len) {
+		/*
+		 * The orginal register name can be suffixed by 'b',
+		 * 'w' or 'd' to indicate its size; so, we need to
+		 * skip this char if we met one.
+		 */
+		char sfx = old_desc[offset];
+
+		if (sfx == 'b' || sfx == 'w'  || sfx == 'd')
+			offset++;
+	}
+
+	if (offset < old_desc_len)
+		memcpy(new_desc + prefix_len + uprobe_len,
+			old_desc + offset, old_desc_len - offset);
+
+	free(old_desc);
+	*pdesc = new_desc;
+
+	return 0;
+}