Revert "Remove CFX_FixedBufGrow"

This reverts commit 55d1d0191ea8316df32858d8cc62fb7c620e8613.

Reason for revert: Slowing down corpus tests by a lot on Mac/Win

Original change's description:
> Remove CFX_FixedBufGrow
> 
> This Cl replaces the CFX_FixedBufGrow class with std::vector.
> 
> Change-Id: I85c85b7a8de4794840b561e09841bb464cfa9dfe
> Reviewed-on: https://pdfium-review.googlesource.com/3138
> Reviewed-by: Tom Sepez <tsepez@chromium.org>
> Commit-Queue: dsinclair <dsinclair@chromium.org>
> 

TBR=tsepez@chromium.org,dsinclair@chromium.org,pdfium-reviews@googlegroups.com
# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: Iaee27570f140b2033b5d8fb8f3077fc839558d64
Reviewed-on: https://pdfium-review.googlesource.com/3158
Reviewed-by: Nicolás Peña <npm@chromium.org>
Commit-Queue: Nicolás Peña <npm@chromium.org>

1 files changed, 27 insertions, 23 deletions

diff --git a/core/fpdfapi/render/cpdf_renderstatus.cpp b/core/fpdfapi/render/cpdf_renderstatus.cpp
index a40a25c5cf..17576fc1f3 100644
--- a/core/fpdfapi/render/cpdf_renderstatus.cpp
+++ b/core/fpdfapi/render/cpdf_renderstatus.cpp
@@ -135,8 +135,9 @@ void DrawAxialShading(CFX_DIBitmap* pBitmap,
   matrix.SetReverse(*pObject2Bitmap);
   uint32_t total_results =
       std::max(CountOutputs(funcs), pCS->CountComponents());
-  std::vector<float> pResults(std::max(16U, total_results));
-  FXSYS_memset(pResults.data(), 0, total_results * sizeof(float));
+  CFX_FixedBufGrow<float, 16> result_array(total_results);
+  float* pResults = result_array;
+  FXSYS_memset(pResults, 0, total_results * sizeof(float));
   uint32_t rgb_array[SHADING_STEPS];
   for (int i = 0; i < SHADING_STEPS; i++) {
     float input = (t_max - t_min) * i / SHADING_STEPS + t_min;
@@ -144,14 +145,14 @@ void DrawAxialShading(CFX_DIBitmap* pBitmap,
     for (const auto& func : funcs) {
       if (func) {
         int nresults = 0;
-        if (func->Call(&input, 1, pResults.data() + offset, &nresults))
+        if (func->Call(&input, 1, pResults + offset, &nresults))
           offset += nresults;
       }
     }
     float R = 0.0f;
     float G = 0.0f;
     float B = 0.0f;
-    pCS->GetRGB(pResults.data(), &R, &G, &B);
+    pCS->GetRGB(pResults, &R, &G, &B);
     rgb_array[i] =
         FXARGB_TODIB(FXARGB_MAKE(alpha, FXSYS_round(R * 255),
                                  FXSYS_round(G * 255), FXSYS_round(B * 255)));
@@ -217,8 +218,9 @@ void DrawRadialShading(CFX_DIBitmap* pBitmap,
   }
   uint32_t total_results =
       std::max(CountOutputs(funcs), pCS->CountComponents());
-  std::vector<float> pResults(std::max(16U, total_results));
-  FXSYS_memset(pResults.data(), 0, total_results * sizeof(float));
+  CFX_FixedBufGrow<float, 16> result_array(total_results);
+  float* pResults = result_array;
+  FXSYS_memset(pResults, 0, total_results * sizeof(float));
   uint32_t rgb_array[SHADING_STEPS];
   for (int i = 0; i < SHADING_STEPS; i++) {
     float input = (t_max - t_min) * i / SHADING_STEPS + t_min;
@@ -226,14 +228,14 @@ void DrawRadialShading(CFX_DIBitmap* pBitmap,
     for (const auto& func : funcs) {
       if (func) {
         int nresults;
-        if (func->Call(&input, 1, pResults.data() + offset, &nresults))
+        if (func->Call(&input, 1, pResults + offset, &nresults))
           offset += nresults;
       }
     }
     float R = 0.0f;
     float G = 0.0f;
     float B = 0.0f;
-    pCS->GetRGB(pResults.data(), &R, &G, &B);
+    pCS->GetRGB(pResults, &R, &G, &B);
     rgb_array[i] =
         FXARGB_TODIB(FXARGB_MAKE(alpha, FXSYS_round(R * 255),
                                  FXSYS_round(G * 255), FXSYS_round(B * 255)));
@@ -341,8 +343,9 @@ void DrawFuncShading(CFX_DIBitmap* pBitmap,
   int pitch = pBitmap->GetPitch();
   uint32_t total_results =
       std::max(CountOutputs(funcs), pCS->CountComponents());
-  std::vector<float> pResults(std::max(16U, total_results));
-  FXSYS_memset(pResults.data(), 0, total_results * sizeof(float));
+  CFX_FixedBufGrow<float, 16> result_array(total_results);
+  float* pResults = result_array;
+  FXSYS_memset(pResults, 0, total_results * sizeof(float));
   for (int row = 0; row < height; row++) {
     uint32_t* dib_buf = (uint32_t*)(pBitmap->GetBuffer() + row * pitch);
     for (int column = 0; column < width; column++) {
@@ -356,7 +359,7 @@ void DrawFuncShading(CFX_DIBitmap* pBitmap,
       for (const auto& func : funcs) {
         if (func) {
           int nresults;
-          if (func->Call(input, 2, pResults.data() + offset, &nresults))
+          if (func->Call(input, 2, pResults + offset, &nresults))
             offset += nresults;
         }
       }
@@ -364,7 +367,7 @@ void DrawFuncShading(CFX_DIBitmap* pBitmap,
       float R = 0.0f;
       float G = 0.0f;
       float B = 0.0f;
-      pCS->GetRGB(pResults.data(), &R, &G, &B);
+      pCS->GetRGB(pResults, &R, &G, &B);
       dib_buf[column] = FXARGB_TODIB(FXARGB_MAKE(
           alpha, (int32_t)(R * 255), (int32_t)(G * 255), (int32_t)(B * 255)));
     }
@@ -2039,13 +2042,13 @@ void CPDF_RenderStatus::DrawShading(CPDF_ShadingPattern* pPattern,
     CPDF_Array* pBackColor = pDict->GetArrayFor("Background");
     if (pBackColor &&
         pBackColor->GetCount() >= pColorSpace->CountComponents()) {
-      std::vector<float> comps(std::max(16U, pColorSpace->CountComponents()));
+      CFX_FixedBufGrow<float, 16> comps(pColorSpace->CountComponents());
       for (uint32_t i = 0; i < pColorSpace->CountComponents(); i++)
         comps[i] = pBackColor->GetNumberAt(i);
       float R = 0.0f;
       float G = 0.0f;
       float B = 0.0f;
-      pColorSpace->GetRGB(comps.data(), &R, &G, &B);
+      pColorSpace->GetRGB(comps, &R, &G, &B);
       background = ArgbEncode(255, (int32_t)(R * 255), (int32_t)(G * 255),
                               (int32_t)(B * 255));
     }
@@ -2573,21 +2576,22 @@ std::unique_ptr<CFX_DIBitmap> CPDF_RenderStatus::LoadSMask(
 
         float R, G, B;
         uint32_t comps = 8;
-        if (pCS->CountComponents() > comps)
+        if (pCS->CountComponents() > comps) {
           comps = pCS->CountComponents();
-
-        std::vector<float> pFloats(std::max(8U, comps));
+        }
+        CFX_FixedBufGrow<float, 8> float_array(comps);
+        float* pFloats = float_array;
         FX_SAFE_UINT32 num_floats = comps;
         num_floats *= sizeof(float);
-        if (!num_floats.IsValid())
+        if (!num_floats.IsValid()) {
           return nullptr;
-
-        FXSYS_memset(pFloats.data(), 0, num_floats.ValueOrDie());
+        }
+        FXSYS_memset(pFloats, 0, num_floats.ValueOrDie());
         size_t count = pBC->GetCount() > 8 ? 8 : pBC->GetCount();
         for (size_t i = 0; i < count; i++) {
           pFloats[i] = pBC->GetNumberAt(i);
         }
-        pCS->GetRGB(pFloats.data(), &R, &G, &B);
+        pCS->GetRGB(pFloats, &R, &G, &B);
         back_color = 0xff000000 | ((int32_t)(R * 255) << 16) |
                      ((int32_t)(G * 255) << 8) | (int32_t)(B * 255);
         m_pContext->GetDocument()->GetPageData()->ReleaseColorSpace(pCSObj);
@@ -2619,11 +2623,11 @@ std::unique_ptr<CFX_DIBitmap> CPDF_RenderStatus::LoadSMask(
   int src_pitch = bitmap.GetPitch();
   std::vector<uint8_t> transfers(256);
   if (pFunc) {
-    std::vector<float> results(std::max(16U, pFunc->CountOutputs()));
+    CFX_FixedBufGrow<float, 16> results(pFunc->CountOutputs());
     for (int i = 0; i < 256; i++) {
       float input = (float)i / 255.0f;
       int nresult;
-      pFunc->Call(&input, 1, results.data(), &nresult);
+      pFunc->Call(&input, 1, results, &nresult);
       transfers[i] = FXSYS_round(results[0] * 255);
     }
   } else {