diff --git a/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments-O0.s b/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments-O0.s
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments-O0.s
@@ -0,0 +1,38 @@
+	.text
+	.section	.AMDGPU.config
+	.long	47176
+	.long	0
+	.long	47180
+	.long	0
+	.long	47200
+	.long	0
+	.long	4
+	.long	0
+	.long	8
+	.long	0
+	.text
+	.hidden	main                            ; -- Begin function main
+	.globl	main
+	.p2align	2
+	.type	main,@function
+main:                                   ; @main
+; %bb.0:
+	s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+	v_add_u32_e64 v1, v0, v0
+                                        ; implicit-def: $sgpr4
+                                        ; implicit-def: $sgpr4
+	v_mul_lo_u32 v0, v1, v0
+	v_sub_u32_e64 v0, v0, v1
+	s_setpc_b64 s[30:31]
+.Lfunc_end0:
+	.size	main, .Lfunc_end0-main
+                                        ; -- End function
+	.section	.AMDGPU.csdata
+; Function info:
+; codeLenInByte = 32
+; NumSgprs: 36
+; NumVgprs: 2
+; ScratchSize: 0
+; MemoryBound: 0
+	.section	".note.GNU-stack"
+	.amd_amdgpu_isa "amdgcn-unknown---gfx900"
diff --git a/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments-O3.s b/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments-O3.s
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments-O3.s
@@ -0,0 +1,36 @@
+	.text
+	.section	.AMDGPU.config
+	.long	47176
+	.long	0
+	.long	47180
+	.long	0
+	.long	47200
+	.long	0
+	.long	4
+	.long	0
+	.long	8
+	.long	0
+	.text
+	.hidden	main                            ; -- Begin function main
+	.globl	main
+	.p2align	2
+	.type	main,@function
+main:                                   ; @main
+; %bb.0:
+	s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+	v_add_u32_e32 v1, v0, v0
+	v_mul_lo_u32 v0, v1, v0
+	v_sub_u32_e32 v0, v0, v1
+	s_setpc_b64 s[30:31]
+.Lfunc_end0:
+	.size	main, .Lfunc_end0-main
+                                        ; -- End function
+	.section	.AMDGPU.csdata
+; Function info:
+; codeLenInByte = 24
+; NumSgprs: 36
+; NumVgprs: 2
+; ScratchSize: 0
+; MemoryBound: 0
+	.section	".note.GNU-stack"
+	.amd_amdgpu_isa "amdgcn-unknown---gfx900"
diff --git a/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments.ll b/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments.ll
--- a/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments.ll
+++ b/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments.ll
@@ -1,5 +1,7 @@
-; RUN: llc -O0 -mtriple=amdgcn- -mcpu=gfx900 < %s | FileCheck -check-prefixes=GCN,GFX9-O0 %s
-; RUN: llc -mtriple=amdgcn- -mcpu=gfx900 < %s | FileCheck -check-prefixes=GCN,GFX9-O3 %s
+; RUN: llc %S/amdgpu_no_merge_comments-O0.s | FileCheck -check-prefixes=GCN,GFX9-O0 %s
+; RUN: llc %S/amdgpu_no_merge_comments-O3.s | FileCheck -check-prefixes=GCN,GFX9-O3 %s
+
+target triple = "amdgcn--"
 
 define hidden i32 @main(i32 %a) {
   %add = add i32 %a, %a
diff --git a/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments.ll.expected b/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments.ll.expected
--- a/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments.ll.expected
+++ b/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/Inputs/amdgpu_no_merge_comments.ll.expected
@@ -1,6 +1,8 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
-; RUN: llc -O0 -mtriple=amdgcn- -mcpu=gfx900 < %s | FileCheck -check-prefixes=GCN,GFX9-O0 %s
-; RUN: llc -mtriple=amdgcn- -mcpu=gfx900 < %s | FileCheck -check-prefixes=GCN,GFX9-O3 %s
+; RUN: llc %S/amdgpu_no_merge_comments-O0.s | FileCheck -check-prefixes=GCN,GFX9-O0 %s
+; RUN: llc %S/amdgpu_no_merge_comments-O3.s | FileCheck -check-prefixes=GCN,GFX9-O3 %s
+
+target triple = "amdgcn--"
 
 define hidden i32 @main(i32 %a) {
 ; GFX9-O0-LABEL: main:
diff --git a/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/amdgpu-no-merge-comments.test b/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/amdgpu-no-merge-comments.test
--- a/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/amdgpu-no-merge-comments.test
+++ b/llvm/test/tools/UpdateTestChecks/update_llc_test_checks/amdgpu-no-merge-comments.test
@@ -1,5 +1,6 @@
 # REQUIRES: amdgpu-registered-target
 ## Check that functions with different IR comments in the output are not merged
 
-# RUN: cp -f %S/Inputs/amdgpu_no_merge_comments.ll %t.ll && %update_llc_test_checks %t.ll
+# RUN: cp -f %S/Inputs/amdgpu_no_merge_comments-O0.s %T/ && cp -f %S/Inputs/amdgpu_no_merge_comments-O3.s %T/
+# RUN: cp -f %S/Inputs/amdgpu_no_merge_comments.ll %t.ll && %update_llc_test_checks --llc-binary cat %t.ll
 # RUN: diff -u %S/Inputs/amdgpu_no_merge_comments.ll.expected %t.ll
diff --git a/llvm/utils/update_llc_test_checks.py b/llvm/utils/update_llc_test_checks.py
--- a/llvm/utils/update_llc_test_checks.py
+++ b/llvm/utils/update_llc_test_checks.py
@@ -88,8 +88,10 @@
         common.warn('Skipping non-FileChecked RUN line: ' + l)
         continue
 
+      sourcedir = os.path.dirname(ti.path)
+
       llc_cmd_args = llc_cmd[len(llc_tool):].strip()
-      llc_cmd_args = llc_cmd_args.replace('< %s', '').replace('%s', '').strip()
+      llc_cmd_args = llc_cmd_args.replace('< %s', '').replace('%s', '').replace('%S', sourcedir).strip()
       if ti.path.endswith('.mir'):
         llc_cmd_args += ' -x mir'
       check_prefixes = [item for m in common.CHECK_PREFIX_RE.finditer(filecheck_cmd)