[llvm] e377430 - [Support] Use APInt::udivrem in DivisionByConstantInfo. NFC

[Craig Topper via llvm-commits]

Author: Craig Topper
Date: 2022-12-23T13:33:40-08:00
New Revision: e3774304a2ead0ff2b6478fc30bf47d8e80de66d

URL: https://github.com/llvm/llvm-project/commit/e3774304a2ead0ff2b6478fc30bf47d8e80de66d
DIFF: https://github.com/llvm/llvm-project/commit/e3774304a2ead0ff2b6478fc30bf47d8e80de66d.diff

LOG: [Support] Use APInt::udivrem in DivisionByConstantInfo. NFC

Added: 
    

Modified: 
    llvm/lib/Support/DivisionByConstantInfo.cpp

Removed: 
    


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diff  --git a/llvm/lib/Support/DivisionByConstantInfo.cpp b/llvm/lib/Support/DivisionByConstantInfo.cpp
index 0a483ac2fd685..989f1f2ed219c 100644
--- a/llvm/lib/Support/DivisionByConstantInfo.cpp
+++ b/llvm/lib/Support/DivisionByConstantInfo.cpp
@@ -27,10 +27,11 @@ SignedDivisionByConstantInfo SignedDivisionByConstantInfo::get(const APInt &D) {
   APInt T = SignedMin + (D.lshr(D.getBitWidth() - 1));
   APInt ANC = T - 1 - T.urem(AD);   // absolute value of NC
   unsigned P = D.getBitWidth() - 1; // initialize P
-  APInt Q1 = SignedMin.udiv(ANC);   // initialize Q1 = 2P/abs(NC)
-  APInt R1 = SignedMin - Q1 * ANC;  // initialize R1 = rem(2P,abs(NC))
-  APInt Q2 = SignedMin.udiv(AD);    // initialize Q2 = 2P/abs(D)
-  APInt R2 = SignedMin - Q2 * AD;   // initialize R2 = rem(2P,abs(D))
+  APInt Q1, R1, Q2, R2;
+  // initialize Q1 = 2P/abs(NC); R1 = rem(2P,abs(NC))
+  APInt::udivrem(SignedMin, ANC, Q1, R1);
+  // initialize Q2 = 2P/abs(D); R2 = rem(2P,abs(D))
+  APInt::udivrem(SignedMin, AD, Q2, R2);
   do {
     P = P + 1;
     Q1 <<= 1;      // update Q1 = 2P/abs(NC)
@@ -75,10 +76,11 @@ UnsignedDivisionByConstantInfo::get(const APInt &D, unsigned LeadingZeros) {
 
   APInt NC = AllOnes - (AllOnes - D).urem(D);
   unsigned P = D.getBitWidth() - 1; // initialize P
-  APInt Q1 = SignedMin.udiv(NC);    // initialize Q1 = 2P/NC
-  APInt R1 = SignedMin - Q1 * NC;   // initialize R1 = rem(2P,NC)
-  APInt Q2 = SignedMax.udiv(D);     // initialize Q2 = (2P-1)/D
-  APInt R2 = SignedMax - Q2 * D;    // initialize R2 = rem((2P-1),D)
+  APInt Q1, R1, Q2, R2;
+  // initialize Q1 = 2P/NC; R1 = rem(2P,NC)
+  APInt::udivrem(SignedMin, NC, Q1, R1);
+  // initialize Q2 = (2P-1)/D; R2 = rem((2P-1),D)
+  APInt::udivrem(SignedMax, D, Q2, R2);
   do {
     P = P + 1;
     if (R1.uge(NC - R1)) {