diff --git a/arch/inst/A/sc.d.yaml b/arch/inst/A/sc.d.yaml
index 019117fb8..7886344e5 100644
--- a/arch/inst/A/sc.d.yaml
+++ b/arch/inst/A/sc.d.yaml
@@ -100,6 +100,7 @@ description: |
   with both bits clear, but may result in lower performance.
 definedBy:
   anyOf: [A, Zalrsc]
+base: 64
 assembly: xd, xs2, xs1
 encoding:
   match: 00011------------011-----0101111
diff --git a/arch/inst/M/divuw.yaml b/arch/inst/M/divuw.yaml
index d5e22cd25..aea69c211 100644
--- a/arch/inst/M/divuw.yaml
+++ b/arch/inst/M/divuw.yaml
@@ -11,6 +11,7 @@ description: |
 
   If the value in rs2 is zero, rd is written with all 1s.
 definedBy: M
+base: 64
 assembly: xd, xs1, xs2
 encoding:
   match: 0000001----------101-----0111011
diff --git a/arch/inst/M/divw.yaml b/arch/inst/M/divw.yaml
index 13031feb0..1f180a746 100644
--- a/arch/inst/M/divw.yaml
+++ b/arch/inst/M/divw.yaml
@@ -15,6 +15,7 @@ description: |
   Division resulting in signed overflow (when most negative number is divided by -1)
   will put the most negative number into rd;
 definedBy: M
+base: 64
 assembly: xd, xs1, xs2
 encoding:
   match: 0000001----------100-----0111011
diff --git a/arch/inst/M/mulw.yaml b/arch/inst/M/mulw.yaml
index d2a24afee..a839db862 100644
--- a/arch/inst/M/mulw.yaml
+++ b/arch/inst/M/mulw.yaml
@@ -17,6 +17,7 @@ description: |
   an alternative is to shift both arguments left by 32 bits, then use MULH[[S]U].
 definedBy:
   anyOf: [M, Zmmul]
+base: 64
 assembly: xd, xs1, xs2
 encoding:
   match: 0000001----------000-----0111011
diff --git a/arch/inst/M/remuw.yaml b/arch/inst/M/remuw.yaml
index c765fa4a6..d6eac0d02 100644
--- a/arch/inst/M/remuw.yaml
+++ b/arch/inst/M/remuw.yaml
@@ -10,6 +10,7 @@ description: |
 
   If the value in rs2 is zero, rd gets the sign-extended value in rs1.
 definedBy: M
+base: 64
 assembly: xd, xs1, xs2
 encoding:
   match: 0000001----------111-----0111011
diff --git a/arch/inst/M/remw.yaml b/arch/inst/M/remw.yaml
index f03753412..1418819ec 100644
--- a/arch/inst/M/remw.yaml
+++ b/arch/inst/M/remw.yaml
@@ -12,6 +12,7 @@ description: |
 
   If the result of the division overflows, write zero into rd;
 definedBy: M
+base: 64
 assembly: xd, xs1, xs2
 encoding:
   match: 0000001----------110-----0111011