[llvm] [X86] Use the Divider resource consistently for scalar integer division (PR #204972)

[Simon Pilgrim via llvm-commits]

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@@ -212,24 +212,15 @@ defm : BWWriteResPair<WriteBEXTR, [BWPort06,BWPort15], 2, [1,1], 2>;
 defm : BWWriteResPair<WriteBLS,   [BWPort15], 1>;
 defm : BWWriteResPair<WriteBZHI,  [BWPort15], 1>;
 
-// TODO: Why isn't the BWDivider used consistently?
-defm : X86WriteRes<WriteDiv8,     [BWPort0, BWDivider], 25, [1, 10], 1>;
-defm : X86WriteRes<WriteDiv16,    [BWPort0,BWPort1,BWPort5,BWPort6,BWPort01,BWPort0156], 80, [7,7,3,3,1,11], 32>;
-defm : X86WriteRes<WriteDiv32,    [BWPort0,BWPort1,BWPort5,BWPort6,BWPort01,BWPort0156], 80, [7,7,3,3,1,11], 32>;
-defm : X86WriteRes<WriteDiv64,    [BWPort0,BWPort1,BWPort5,BWPort6,BWPort01,BWPort0156], 80, [7,7,3,3,1,11], 32>;
-defm : X86WriteRes<WriteDiv8Ld,   [BWPort0,BWPort1,BWPort5,BWPort23,BWPort0156], 34, [2,2,2,1,1], 8>;
-defm : X86WriteRes<WriteDiv16Ld,  [BWPort0,BWPort1,BWPort5,BWPort23,BWPort0156], 34, [2,2,2,1,1], 8>;
-defm : X86WriteRes<WriteDiv32Ld,  [BWPort0,BWPort1,BWPort5,BWPort23,BWPort0156], 34, [2,2,2,1,1], 8>;
-defm : X86WriteRes<WriteDiv64Ld,  [BWPort0,BWPort1,BWPort5,BWPort23,BWPort0156], 34, [2,2,2,1,1], 8>;
-
-defm : X86WriteRes<WriteIDiv8,    [BWPort0, BWDivider], 25, [1,10], 1>;
-defm : X86WriteRes<WriteIDiv16,   [BWPort0, BWDivider], 25, [1,10], 1>;
-defm : X86WriteRes<WriteIDiv32,   [BWPort0, BWDivider], 25, [1,10], 1>;
-defm : X86WriteRes<WriteIDiv64,   [BWPort0, BWDivider], 25, [1,10], 1>;
-defm : X86WriteRes<WriteIDiv8Ld,  [BWPort0,BWPort1,BWPort5,BWPort23,BWPort0156], 35, [2,2,2,1,1], 8>;
-defm : X86WriteRes<WriteIDiv16Ld, [BWPort0,BWPort1,BWPort5,BWPort23,BWPort0156], 35, [2,2,2,1,1], 8>;
-defm : X86WriteRes<WriteIDiv32Ld, [BWPort0,BWPort1,BWPort5,BWPort23,BWPort0156], 35, [2,2,2,1,1], 8>;
-defm : X86WriteRes<WriteIDiv64Ld, [BWPort0,BWPort1,BWPort5,BWPort23,BWPort0156], 35, [2,2,2,1,1], 8>;
+defm : BWWriteResPair<WriteDiv8,  [BWPort0, BWDivider], 24, [1,9],   9>;
+defm : BWWriteResPair<WriteDiv16, [BWPort0, BWDivider], 25, [1,9],  11>;
+defm : BWWriteResPair<WriteDiv32, [BWPort0, BWDivider], 28, [1,9],  10>;
+defm : BWWriteResPair<WriteDiv64, [BWPort0, BWDivider], 92, [1,21], 36>;
+
+defm : BWWriteResPair<WriteIDiv8,  [BWPort0, BWDivider], 24, [1,6],  9>;
+defm : BWWriteResPair<WriteIDiv16, [BWPort0, BWDivider], 26, [1,6], 10>;
+defm : BWWriteResPair<WriteIDiv32, [BWPort0, BWDivider], 28, [1,6],  9>;
+defm : BWWriteResPair<WriteIDiv64, [BWPort0, BWDivider], 100, [1,24], 59>;
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RKSimon wrote:

These don't look right to me - the regular ports still have high resource usage (like the uops.info numbers indicate) - Divider is a psuedo-resource buffer to ensure that only a single div/idiv is scheduled per-cycle

https://github.com/llvm/llvm-project/pull/204972