diff --git a/llvm/test/tools/llvm-cgdata/empty.test b/llvm/test/tools/llvm-cgdata/empty.test
index 2082eca58f073..52d0dfb87623f 100644
--- a/llvm/test/tools/llvm-cgdata/empty.test
+++ b/llvm/test/tools/llvm-cgdata/empty.test
@@ -29,9 +29,9 @@ RUN: llvm-cgdata --convert %t_emptyheader.cgdata --format text | count 0
 #   uint64_t OutlinedHashTreeOffset;
 #   uint64_t StableFunctionMapOffset;
 # }
-RUN: printf '\xffcgdata\x81' > %t_header.cgdata
-RUN: printf '\x04\x00\x00\x00' >> %t_header.cgdata
-RUN: printf '\x00\x00\x00\x00' >> %t_header.cgdata
-RUN: printf '\x20\x00\x00\x00\x00\x00\x00\x00' >> %t_header.cgdata
-RUN: printf '\x20\x00\x00\x00\x00\x00\x00\x00' >> %t_header.cgdata
+RUN: printf '\377cgdata\201' > %t_header.cgdata
+RUN: printf '\004\000\000\000' >> %t_header.cgdata
+RUN: printf '\000\000\000\000' >> %t_header.cgdata
+RUN: printf '\040\000\000\000\000\000\000\000' >> %t_header.cgdata
+RUN: printf '\040\000\000\000\000\000\000\000' >> %t_header.cgdata
 RUN: diff %t_header.cgdata %t_emptyheader.cgdata
diff --git a/llvm/test/tools/llvm-cgdata/error.test b/llvm/test/tools/llvm-cgdata/error.test
index 9484371848a72..bf5e3ff6a4ed0 100644
--- a/llvm/test/tools/llvm-cgdata/error.test
+++ b/llvm/test/tools/llvm-cgdata/error.test
@@ -13,29 +13,29 @@ RUN: not llvm-cgdata --show %t_empty.cgdata 2>&1 | FileCheck %s --check-prefix=E
 EMPTY: {{.}}cgdata: empty codegen data
 
 # Not a magic.
-RUN: printf '\xff' > %t_malformed.cgdata
+RUN: printf '\377' > %t_malformed.cgdata
 RUN: not llvm-cgdata --show %t_malformed.cgdata 2>&1 | FileCheck %s --check-prefix=MALFORMED
 MALFORMED: {{.}}cgdata: malformed codegen data
 
 # The minimum header size is 24.
-RUN: printf '\xffcgdata\x81' > %t_corrupt.cgdata
+RUN: printf '\377cgdata\201' > %t_corrupt.cgdata
 RUN: not llvm-cgdata --show %t_corrupt.cgdata 2>&1 | FileCheck %s  --check-prefix=CORRUPT
 CORRUPT: {{.}}cgdata: invalid codegen data (file header is corrupt)
 
 # The current version 4 while the header says 5.
-RUN: printf '\xffcgdata\x81' > %t_version.cgdata
-RUN: printf '\x05\x00\x00\x00' >> %t_version.cgdata
-RUN: printf '\x00\x00\x00\x00' >> %t_version.cgdata
-RUN: printf '\x20\x00\x00\x00\x00\x00\x00\x00' >> %t_version.cgdata
-RUN: printf '\x20\x00\x00\x00\x00\x00\x00\x00' >> %t_version.cgdata
+RUN: printf '\377cgdata\201' > %t_version.cgdata
+RUN: printf '\005\000\000\000' >> %t_version.cgdata
+RUN: printf '\000\000\000\000' >> %t_version.cgdata
+RUN: printf '\040\000\000\000\000\000\000\000' >> %t_version.cgdata
+RUN: printf '\040\000\000\000\000\000\000\000' >> %t_version.cgdata
 RUN: not llvm-cgdata --show %t_version.cgdata 2>&1 | FileCheck %s  --check-prefix=BAD_VERSION
 BAD_VERSION: {{.}}cgdata: unsupported codegen data version
 
 # Header says an outlined hash tree, but the file ends after the header.
-RUN: printf '\xffcgdata\x81' > %t_eof.cgdata
-RUN: printf '\x02\x00\x00\x00' >> %t_eof.cgdata
-RUN: printf '\x01\x00\x00\x00' >> %t_eof.cgdata
-RUN: printf '\x20\x00\x00\x00\x00\x00\x00\x00' >> %t_eof.cgdata
-RUN: printf '\x20\x00\x00\x00\x00\x00\x00\x00' >> %t_eof.cgdata
+RUN: printf '\377cgdata\201' > %t_eof.cgdata
+RUN: printf '\002\000\000\000' >> %t_eof.cgdata
+RUN: printf '\001\000\000\000' >> %t_eof.cgdata
+RUN: printf '\040\000\000\000\000\000\000\000' >> %t_eof.cgdata
+RUN: printf '\040\000\000\000\000\000\000\000' >> %t_eof.cgdata
 RUN: not llvm-cgdata --show %t_eof.cgdata 2>&1 | FileCheck %s  --check-prefix=EOF
 EOF: {{.}}cgdata: end of File
diff --git a/llvm/test/tools/llvm-gsymutil/X86/elf-dwarf.yaml b/llvm/test/tools/llvm-gsymutil/X86/elf-dwarf.yaml
index 78795c62ec3ed..a01d63905cf89 100644
--- a/llvm/test/tools/llvm-gsymutil/X86/elf-dwarf.yaml
+++ b/llvm/test/tools/llvm-gsymutil/X86/elf-dwarf.yaml
@@ -5,7 +5,7 @@
 # RUN: yaml2obj %s -o %t
 # RUN: llvm-gsymutil --convert %t -o %t.gsym 2>&1 | FileCheck %s --check-prefix=CONVERT
 # RUN: llvm-gsymutil --address=0x400391 --address=0x4004cd %t.gsym 2>&1 | FileCheck %s --check-prefix=ADDR
-# RUN: echo -e "0x400391 %/t.gsym\n0x4004cd %/t.gsym" | llvm-gsymutil --addresses-from-stdin  2>&1 | FileCheck %s --check-prefix=ADDRI --dump-input=always
+# RUN: printf "0x400391 %/t.gsym\n0x4004cd %/t.gsym" | llvm-gsymutil --addresses-from-stdin  2>&1 | FileCheck %s --check-prefix=ADDRI --dump-input=always
 # RUN: llvm-gsymutil --address=0x400391 --address=0x4004cd --verbose %t.gsym 2>&1 | FileCheck %s --check-prefix=ADDRV --dump-input=always
 # RUN: llvm-gsymutil --address=0x400391 --address=0x4004cd --verbose %t.gsym 2>&1 | FileCheck %s --check-prefix=ADDRV --dump-input=always
 # RUN: llvm-gsymutil %t.gsym 2>&1 | FileCheck %s --check-prefix=DUMP
diff --git a/llvm/test/tools/llvm-objcopy/ELF/add-invalid-note.test b/llvm/test/tools/llvm-objcopy/ELF/add-invalid-note.test
index 9a28bbb9aa308..d4b535352020c 100644
--- a/llvm/test/tools/llvm-objcopy/ELF/add-invalid-note.test
+++ b/llvm/test/tools/llvm-objcopy/ELF/add-invalid-note.test
@@ -3,22 +3,22 @@
 ## Add [namesz, descsz, type, name, desc] for a build id.
 
 ## Notes should be padded to 8 bytes.
-# RUN: printf "\x04\x00\x00\x00" >  %t-miss-padding-note.bin
-# RUN: printf "\x07\x00\x00\x00" >> %t-miss-padding-note.bin
-# RUN: printf "\x03\x00\x00\x00" >> %t-miss-padding-note.bin
-# RUN: printf "GNU\x00"          >> %t-miss-padding-note.bin
-# RUN: printf "\x0c\x0d\x0e"     >> %t-miss-padding-note.bin
+# RUN: printf "\004\000\000\000" >  %t-miss-padding-note.bin
+# RUN: printf "\007\000\000\000" >> %t-miss-padding-note.bin
+# RUN: printf "\003\000\000\000" >> %t-miss-padding-note.bin
+# RUN: printf "GNU\000"          >> %t-miss-padding-note.bin
+# RUN: printf "\014\015\016"     >> %t-miss-padding-note.bin
 
 ## The namesz field bit is incorrect.
-# RUN: printf "\x08\x00\x00\x00" >  %t-invalid-size-note.bin
-# RUN: printf "\x07\x00\x00\x00" >> %t-invalid-size-note.bin
-# RUN: printf "\x03\x00\x00\x00" >> %t-invalid-size-note.bin
-# RUN: printf "GNU\x00"          >> %t-invalid-size-note.bin
-# RUN: printf "\x0c\x0d\x0e\x00" >> %t-invalid-size-note.bin
+# RUN: printf "\010\000\000\000" >  %t-invalid-size-note.bin
+# RUN: printf "\007\000\000\000" >> %t-invalid-size-note.bin
+# RUN: printf "\003\000\000\000" >> %t-invalid-size-note.bin
+# RUN: printf "GNU\000"          >> %t-invalid-size-note.bin
+# RUN: printf "\014\015\016\000" >> %t-invalid-size-note.bin
 
 ## Missing type field.
-# RUN: printf "\x08\x00\x00\x00" >  %t-short-note.bin
-# RUN: printf "\x07\x00\x00\x00" >> %t-short-note.bin
+# RUN: printf "\010\000\000\000" >  %t-short-note.bin
+# RUN: printf "\007\000\000\000" >> %t-short-note.bin
 
 # RUN: yaml2obj %s -o %t.o
 
@@ -33,11 +33,11 @@
 # CHECK-SHORT: .note.short data must be either empty or at least 12 bytes long
 
 ## Test compatibility with .note.gnu.property, which has 8-byte alignment.
-# RUN: printf "\x04\x00\x00\x00\x40\x00\x00\x00\x05\x00\x00\x00\x47\x4e\x55\x00" >  %t-note-gnu-property.bin
-# RUN: printf "\x02\x00\x00\xc0\x04\x00\x00\x00\x03\x00\x00\x00\x00\x00\x00\x00" >> %t-note-gnu-property.bin
-# RUN: printf "\x01\x80\x01\xc0\x04\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00" >> %t-note-gnu-property.bin
-# RUN: printf "\x01\x00\x01\xc0\x04\x00\x00\x00\x0b\x00\x00\x00\x00\x00\x00\x00" >> %t-note-gnu-property.bin
-# RUN: printf "\x02\x00\x01\xc0\x04\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00" >> %t-note-gnu-property.bin
+# RUN: printf "\004\000\000\000\100\000\000\000\005\000\000\000\107\116\125\000" >  %t-note-gnu-property.bin
+# RUN: printf "\002\000\000\300\004\000\000\000\003\000\000\000\000\000\000\000" >> %t-note-gnu-property.bin
+# RUN: printf "\001\200\001\300\004\000\000\000\001\000\000\000\000\000\000\000" >> %t-note-gnu-property.bin
+# RUN: printf "\001\000\001\300\004\000\000\000\013\000\000\000\000\000\000\000" >> %t-note-gnu-property.bin
+# RUN: printf "\002\000\001\300\004\000\000\000\001\000\000\000\000\000\000\000" >> %t-note-gnu-property.bin
 # RUN: llvm-objcopy --add-section=.note.gnu.property=%t-note-gnu-property.bin %t.o %t-with-note-gnu-property.o
 
 ## Test that verification can be disabled.
diff --git a/llvm/test/tools/llvm-profdata/binary-ids-padding.test b/llvm/test/tools/llvm-profdata/binary-ids-padding.test
index 292c582b45c52..cc3e6c38e6907 100644
--- a/llvm/test/tools/llvm-profdata/binary-ids-padding.test
+++ b/llvm/test/tools/llvm-profdata/binary-ids-padding.test
@@ -69,7 +69,7 @@ RUN: printf '\0\0\0\0\0\0\0\0' >> %t.profraw
 
 RUN: printf '\067\265\035\031\112\165\023\344' >> %t.profraw
 RUN: printf '\02\0\0\0\0\0\0\0' >> %t.profraw
-RUN: printf '\xc8\xff\3\0\1\0\0\0' >> %t.profraw
+RUN: printf '\310\377\3\0\1\0\0\0' >> %t.profraw
 RUN: printf '\0\0\0\0\0\0\0\0' >> %t.profraw
 RUN: printf '\0\0\0\0\0\0\0\0' >> %t.profraw
 RUN: printf '\0\0\0\0\0\0\0\0' >> %t.profraw
diff --git a/llvm/test/tools/llvm-profdata/raw-32-bits-be.test b/llvm/test/tools/llvm-profdata/raw-32-bits-be.test
index fbd73ae30a5b3..6b3dc96b36270 100644
--- a/llvm/test/tools/llvm-profdata/raw-32-bits-be.test
+++ b/llvm/test/tools/llvm-profdata/raw-32-bits-be.test
@@ -31,8 +31,8 @@ RUN: printf '\0\0\0\3' >> %t
 
 RUN: printf '\344\023\165\112\031\035\265\067' >> %t
 RUN: printf '\0\0\0\0\0\0\0\2' >> %t
-RUN: printf '\0\xff\xff\xd8' >> %t
-RUN: printf '\2\xff\xff\xd3' >> %t
+RUN: printf '\0\377\377\330' >> %t
+RUN: printf '\2\377\377\323' >> %t
 RUN: printf '\0\0\0\0' >> %t
 RUN: printf '\0\0\0\0' >> %t
 RUN: printf '\0\0\0\2' >> %t
diff --git a/llvm/test/tools/llvm-profdata/raw-32-bits-le.test b/llvm/test/tools/llvm-profdata/raw-32-bits-le.test
index 91f10fc874586..95625565f5c0c 100644
--- a/llvm/test/tools/llvm-profdata/raw-32-bits-le.test
+++ b/llvm/test/tools/llvm-profdata/raw-32-bits-le.test
@@ -30,8 +30,8 @@ RUN: printf '\3\0\0\0' >> %t
 
 RUN: printf '\067\265\035\031\112\165\023\344' >> %t
 RUN: printf '\02\0\0\0\0\0\0\0' >> %t
-RUN: printf '\xd8\xff\xff\0' >> %t
-RUN: printf '\xd3\xff\xff\2' >> %t
+RUN: printf '\330\377\377\0' >> %t
+RUN: printf '\323\377\377\2' >> %t
 RUN: printf '\0\0\0\0' >> %t
 RUN: printf '\0\0\0\0' >> %t
 RUN: printf '\2\0\0\0' >> %t
diff --git a/llvm/test/tools/llvm-profdata/raw-64-bits-be.test b/llvm/test/tools/llvm-profdata/raw-64-bits-be.test
index e7694a1b5a73b..5316ef5a3e559 100644
--- a/llvm/test/tools/llvm-profdata/raw-64-bits-be.test
+++ b/llvm/test/tools/llvm-profdata/raw-64-bits-be.test
@@ -30,8 +30,8 @@ RUN: printf '\0\0\0\3' >> %t
 
 RUN: printf '\344\023\165\112\031\035\265\067' >> %t
 RUN: printf '\0\0\0\0\0\0\0\02' >> %t
-RUN: printf '\0\0\0\1\0\3\xff\xc8' >> %t
-RUN: printf '\0\0\0\3\0\3\xff\xc3' >> %t
+RUN: printf '\0\0\0\1\0\3\377\310' >> %t
+RUN: printf '\0\0\0\3\0\3\377\303' >> %t
 RUN: printf '\0\0\0\0\0\0\0\0' >> %t
 RUN: printf '\0\0\0\0\0\0\0\0' >> %t
 RUN: printf '\0\0\0\02' >> %t
diff --git a/llvm/test/tools/llvm-profdata/raw-64-bits-le.test b/llvm/test/tools/llvm-profdata/raw-64-bits-le.test
index 99d486b8a5176..58f4da8cf0386 100644
--- a/llvm/test/tools/llvm-profdata/raw-64-bits-le.test
+++ b/llvm/test/tools/llvm-profdata/raw-64-bits-le.test
@@ -30,8 +30,8 @@ RUN: printf '\3\0\0\0' >> %t
 
 RUN: printf '\067\265\035\031\112\165\023\344' >> %t
 RUN: printf '\02\0\0\0\0\0\0\0' >> %t
-RUN: printf '\xc8\xff\3\0\1\0\0\0' >> %t
-RUN: printf '\xc3\xff\3\0\3\0\0\0' >> %t
+RUN: printf '\310\377\3\0\1\0\0\0' >> %t
+RUN: printf '\303\377\3\0\3\0\0\0' >> %t
 RUN: printf '\0\0\0\0\0\0\0\0' >> %t
 RUN: printf '\0\0\0\0\0\0\0\0' >> %t
 RUN: printf '\02\0\0\0' >> %t
diff --git a/llvm/test/tools/llvm-strings/negative-char.test b/llvm/test/tools/llvm-strings/negative-char.test
index 8c60685bf70c1..5154886f9200f 100644
--- a/llvm/test/tools/llvm-strings/negative-char.test
+++ b/llvm/test/tools/llvm-strings/negative-char.test
@@ -1,6 +1,6 @@
 ## Show that llvm-strings can handle a negative signed char value (i.e. > 0x7f).
 ## Such characters should form string delimiters like other unprintable ones.
 
-# RUN: echo -e "z\0\x80\0a\0" | llvm-strings --bytes 1 - | FileCheck %s
+# RUN: printf "z\0\200\0a\0" | llvm-strings --bytes 1 - | FileCheck %s
 # CHECK: z{{$}}
 # CHECK-NEXT: {{^}}a
diff --git a/llvm/test/tools/llvm-strings/stdin.test b/llvm/test/tools/llvm-strings/stdin.test
index 9af474ca7ea76..06dcd194a3016 100644
--- a/llvm/test/tools/llvm-strings/stdin.test
+++ b/llvm/test/tools/llvm-strings/stdin.test
@@ -8,12 +8,12 @@ CASE1: abcdefg
 RUN: echo -n "abc" | llvm-strings - | FileCheck %s --implicit-check-not={{.}} --allow-empty
 
 ## Case 3: output with new line.
-RUN: echo -e "abcd\nefgh" | llvm-strings - | FileCheck %s --check-prefix=CASE3 --implicit-check-not={{.}}
+RUN: printf "abcd\nefgh" | llvm-strings - | FileCheck %s --check-prefix=CASE3 --implicit-check-not={{.}}
 CASE3:      abcd
 CASE3-NEXT: efgh
 
 ## Case 4: output containing unprintable characters.
-RUN: echo -e "abcd\x00ef\x1fghij\x7fklmn" | llvm-strings - | FileCheck %s --check-prefix=CASE4 --implicit-check-not={{.}}
+RUN: printf "abcd\000ef\037ghij\177klmn" | llvm-strings - | FileCheck %s --check-prefix=CASE4 --implicit-check-not={{.}}
 CASE4:      abcd
 CASE4-NEXT: ghij
 CASE4-NEXT: klmn
diff --git a/llvm/test/tools/llvm-symbolizer/basic.s b/llvm/test/tools/llvm-symbolizer/basic.s
index 1a28f14f3eb4a..ac15da9156c01 100644
--- a/llvm/test/tools/llvm-symbolizer/basic.s
+++ b/llvm/test/tools/llvm-symbolizer/basic.s
@@ -8,8 +8,8 @@ foo:
 # RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o -g
 
 # Check input addresses specified on stdin.
-# RUN: echo -e "0xa\n0xb" | llvm-symbolizer --obj=%t.o | FileCheck %s
-# RUN: echo -e "10\n11" | llvm-symbolizer --obj=%t.o | FileCheck %s
+# RUN: printf "0xa\n0xb" | llvm-symbolizer --obj=%t.o | FileCheck %s
+# RUN: printf "10\n11" | llvm-symbolizer --obj=%t.o | FileCheck %s
 
 # Check input addresses specified on the command-line.
 # RUN: llvm-symbolizer 0xa 0xb --obj=%t.o | FileCheck %s
diff --git a/llvm/test/tools/llvm-symbolizer/split-dwarf-dwp.test b/llvm/test/tools/llvm-symbolizer/split-dwarf-dwp.test
index cadc5592961c7..cac9d9f52648c 100644
--- a/llvm/test/tools/llvm-symbolizer/split-dwarf-dwp.test
+++ b/llvm/test/tools/llvm-symbolizer/split-dwarf-dwp.test
@@ -3,7 +3,7 @@ RUN: mkdir -p %t
 
 RUN: cp %p/Inputs/split-dwarf-dwp.o %t/split-dwarf-dwp-different-name.o
 
-RUN: echo -e 'DATA 0\n0x54' | \
+RUN: printf 'DATA 0\n0x54' | \
 RUN:     llvm-symbolizer --dwp=%p/Inputs/split-dwarf-dwp.o.dwp \
 RUN:     --obj=%t/split-dwarf-dwp-different-name.o | FileCheck %s
 
diff --git a/llvm/test/tools/sanstats/elf.test b/llvm/test/tools/sanstats/elf.test
index b8f2d5d5b4f99..e230fbdc435fb 100644
--- a/llvm/test/tools/sanstats/elf.test
+++ b/llvm/test/tools/sanstats/elf.test
@@ -1,27 +1,27 @@
 # RUN: yaml2obj %s -o %t1.o
 # RUN: yaml2obj %s -o %t2.o
 
-# RUN: printf "\x04" > %t.stats
+# RUN: printf "\004" > %t.stats
 
 # RUN: printf "%%s" "%t1.o" >> %t.stats
-# RUN: printf "\x00" >> %t.stats
-# RUN: printf "\x01\x00\x00\x00\x01\x00\x00\x00" >> %t.stats
-# RUN: printf "\x11\x00\x00\x00\x02\x00\x00\x20" >> %t.stats
-# RUN: printf "\x21\x00\x00\x00\x03\x00\x00\x40" >> %t.stats
-# RUN: printf "\x01\x00\x00\x00\x04\x00\x00\x60" >> %t.stats
-# RUN: printf "\x11\x00\x00\x00\x05\x00\x00\x80" >> %t.stats
-# RUN: printf "\x21\x00\x00\x00\x06\x00\x00\xa0" >> %t.stats
-# RUN: printf "\x00\x00\x00\x00\x00\x00\x00\x00" >> %t.stats
+# RUN: printf "\000" >> %t.stats
+# RUN: printf "\001\000\000\000\001\000\000\000" >> %t.stats
+# RUN: printf "\021\000\000\000\002\000\000\040" >> %t.stats
+# RUN: printf "\041\000\000\000\003\000\000\100" >> %t.stats
+# RUN: printf "\001\000\000\000\004\000\000\140" >> %t.stats
+# RUN: printf "\021\000\000\000\005\000\000\200" >> %t.stats
+# RUN: printf "\041\000\000\000\006\000\000\240" >> %t.stats
+# RUN: printf "\000\000\000\000\000\000\000\000" >> %t.stats
 
 # RUN: printf "%%s" "%t2.o" >> %t.stats
-# RUN: printf "\x00" >> %t.stats
-# RUN: printf "\x21\x00\x00\x00\x07\x00\x00\x00" >> %t.stats
-# RUN: printf "\x11\x00\x00\x00\x08\x00\x00\x20" >> %t.stats
-# RUN: printf "\x01\x00\x00\x00\x09\x00\x00\x40" >> %t.stats
-# RUN: printf "\x21\x00\x00\x00\x0b\x00\x00\x60" >> %t.stats
-# RUN: printf "\x11\x00\x00\x00\x0c\x00\x00\x80" >> %t.stats
-# RUN: printf "\x01\x00\x00\x00\x0e\x00\x00\xa0" >> %t.stats
-# RUN: printf "\x00\x00\x00\x00\x00\x00\x00\x00" >> %t.stats
+# RUN: printf "\000" >> %t.stats
+# RUN: printf "\041\000\000\000\007\000\000\000" >> %t.stats
+# RUN: printf "\021\000\000\000\010\000\000\040" >> %t.stats
+# RUN: printf "\001\000\000\000\011\000\000\100" >> %t.stats
+# RUN: printf "\041\000\000\000\013\000\000\140" >> %t.stats
+# RUN: printf "\021\000\000\000\014\000\000\200" >> %t.stats
+# RUN: printf "\001\000\000\000\016\000\000\240" >> %t.stats
+# RUN: printf "\000\000\000\000\000\000\000\000" >> %t.stats
 
 # RUN: sanstats %t.stats | FileCheck %s