feat(crandall reduction): prevent asm for mul on 32-bit

mratsim · Jul 27, 2024 · 49f0646 · 49f0646
1 parent 15788c8
commit 49f0646
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Showing 2 changed files with 6 additions and 4 deletions.
diff --git a/constantine/math/arithmetic/assembly/limbs_asm_crandall_x86.nim b/constantine/math/arithmetic/assembly/limbs_asm_crandall_x86.nim
@@ -235,6 +235,7 @@ func mulCranPartialReduce_asm*[N: static int](
         r: var Limbs[N],
         a, b: Limbs[N],
         m: static int, c: static SecretWord) =
+  static: doAssert UseASM_X86_64, "x86-32 does not have enough registers for multiplication"
   var r2 {.noInit.}: Limbs[2*N]
   r2.mul_asm(a, b)
   r.reduceCrandallPartial_asm(r2, m, c)
@@ -243,6 +244,7 @@ func squareCranPartialReduce_asm*[N: static int](
         r: var Limbs[N],
         a: Limbs[N],
         m: static int, c: static SecretWord) =
+  static: doAssert UseASM_X86_64, "x86-32 does not have enough registers for squaring"
   var r2 {.noInit.}: Limbs[2*N]
   r2.square_asm(a)
   r.reduceCrandallPartial_asm(r2, m, c)

diff --git a/constantine/math/arithmetic/limbs_crandall.nim b/constantine/math/arithmetic/limbs_crandall.nim
@@ -187,7 +187,7 @@ func mulCranPartialReduce[N: static int](
         r: var Limbs[N],
         a, b: Limbs[N],
         m: static int, c: static SecretWord) {.inline.} =
-  when UseASM_X86_32 and a.len in {3..6}:
+  when UseASM_X86_64 and a.len in {3..6}:
     # ADX implies BMI2
     if ({.noSideEffect.}: hasAdx()):
       r.mulCranPartialReduce_asm_adx(a, b, m, c)
@@ -206,7 +206,7 @@ func mulCran*[N: static int](
         lazyReduce: static bool = false) {.inline.} =
   when lazyReduce:
     r.mulCranPartialReduce(a, b, m, c)
-  elif UseASM_X86_32 and a.len in {3..6}:
+  elif UseASM_X86_64 and a.len in {3..6}:
     # ADX implies BMI2
     if ({.noSideEffect.}: hasAdx()):
       r.mulCran_asm_adx(a, b, p, m, c)
@@ -222,7 +222,7 @@ func squareCranPartialReduce[N: static int](
         r: var Limbs[N],
         a: Limbs[N],
         m: static int, c: static SecretWord) {.inline.} =
-  when UseASM_X86_32 and a.len in {3..6}:
+  when UseASM_X86_64 and a.len in {3..6}:
     # ADX implies BMI2
     if ({.noSideEffect.}: hasAdx()):
       r.squareCranPartialReduce_asm_adx(a, m, c)
@@ -241,7 +241,7 @@ func squareCran*[N: static int](
         lazyReduce: static bool = false) {.inline.} =
   when lazyReduce:
     r.squareCranPartialReduce(a, m, c)
-  elif UseASM_X86_32 and a.len in {3..6}:
+  elif UseASM_X86_64 and a.len in {3..6}:
     # ADX implies BMI2
     if ({.noSideEffect.}: hasAdx()):
       r.squareCran_asm_adx(a, p, m, c)